Re: [PATCH v2 26/50] KVM: PPC: Move processor compatibility check to module init
Sean Christopherson writes:
> Move KVM PPC's compatibility checks to their respective module_init()
> hooks, there's no need to wait until KVM's common compat check, nor is
> there a need to perform the check on every CPU (provided by common KVM's
> hook), as the compatibility checks operate on global data.
>
> arch/powerpc/include/asm/cputable.h: extern struct cpu_spec *cur_cpu_spec;
> arch/powerpc/kvm/book3s.c: return 0
> arch/powerpc/kvm/e500.c: strcmp(cur_cpu_spec->cpu_name, "e500v2")
> arch/powerpc/kvm/e500mc.c: strcmp(cur_cpu_spec->cpu_name, "e500mc")
> strcmp(cur_cpu_spec->cpu_name, "e5500")
> strcmp(cur_cpu_spec->cpu_name, "e6500")
I'm not sure that output is really useful in the change log unless you
explain more about what it is.
> diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
> index 57e0ad6a2ca3..795667f7ebf0 100644
> --- a/arch/powerpc/kvm/e500mc.c
> +++ b/arch/powerpc/kvm/e500mc.c
> @@ -388,6 +388,10 @@ static int __init kvmppc_e500mc_init(void)
> {
> int r;
>
> + r = kvmppc_e500mc_check_processor_compat();
> + if (r)
> + return kvmppc_e500mc;
This doesn't build:
linux/arch/powerpc/kvm/e500mc.c: In function ‘kvmppc_e500mc_init’:
linux/arch/powerpc/kvm/e500mc.c:391:13: error: implicit declaration of function
‘kvmppc_e500mc_check_processor_compat’; did you mean
‘kvmppc_core_check_processor_compat’? [-Werror=implicit-function-declaration]
391 | r = kvmppc_e500mc_check_processor_compat();
| ^~~~
| kvmppc_core_check_processor_compat
linux/arch/powerpc/kvm/e500mc.c:393:24: error: ‘kvmppc_e500mc’ undeclared
(first use in this function); did you mean ‘kvm_ops_e500mc’?
393 | return kvmppc_e500mc;
|^
|kvm_ops_e500mc
linux/arch/powerpc/kvm/e500mc.c:393:24: note: each undeclared identifier is
reported only once for each function it appears in
It needs the delta below to compile.
With that:
Acked-by: Michael Ellerman (powerpc)
cheers
diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
index 795667f7ebf0..4564aa27edcf 100644
--- a/arch/powerpc/kvm/e500mc.c
+++ b/arch/powerpc/kvm/e500mc.c
@@ -168,7 +168,7 @@ static void kvmppc_core_vcpu_put_e500mc(struct kvm_vcpu
*vcpu)
kvmppc_booke_vcpu_put(vcpu);
}
-int kvmppc_core_check_processor_compat(void)
+int kvmppc_e500mc_check_processor_compat(void)
{
int r;
@@ -390,7 +390,7 @@ static int __init kvmppc_e500mc_init(void)
r = kvmppc_e500mc_check_processor_compat();
if (r)
- return kvmppc_e500mc;
+ goto err_out;
r = kvmppc_booke_init();
if (r)
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Re: [PATCH 32/44] KVM: x86: Unify pr_fmt to use module name for all KVM modules
On Wed, 2022-11-30 at 23:02 +, Sean Christopherson wrote: > On Thu, Nov 10, 2022, Sean Christopherson wrote: > > On Thu, Nov 10, 2022, Robert Hoo wrote: > > > After this patch set, still find some printk()s left in > > > arch/x86/kvm/*, > > > consider clean all of them up? > > > > Hmm, yeah, I suppose at this point it makes sense to tack on a > > patch to clean > > them up. > > Actually, I'm going to pass on this for now. The series is already > too big. I'll > add this to my todo list for the future. That's all right, thanks for update. ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
Re: [PATCH 2/4] KVM: arm64: Don't serialize if the access flag isn't set
On Wed, Nov 30, 2022 at 08:21:17AM +, Marc Zyngier wrote: > On Wed, 30 Nov 2022 01:23:20 +, > Ricardo Koller wrote: > > > > On Tue, Nov 29, 2022 at 09:15:21PM +, Oliver Upton wrote: > > > Hi Ricardo, > > > > > > Thanks for having a look. > > > > > > On Tue, Nov 29, 2022 at 12:52:12PM -0800, Ricardo Koller wrote: > > > > On Tue, Nov 29, 2022 at 07:19:44PM +, Oliver Upton wrote: > > > > > > [...] > > > > > > > > + ret = stage2_update_leaf_attrs(pgt, addr, 1, > > > > > KVM_PTE_LEAF_ATTR_LO_S2_AF, 0, > > > > > +, NULL, 0); > > > > > + if (!ret) > > > > > + dsb(ishst); > > > > > > > > At the moment, the only reason for stage2_update_leaf_attrs() to not > > > > update the PTE is if it's not valid: > > > > > > > > if (!kvm_pte_valid(pte)) > > > > return 0; > > > > > > > > I guess you could check that as well: > > > > > > > > + if (!ret || kvm_pte_valid(pte)) > > > > + dsb(ishst); > > > > > > Thanks for catching this. > > > > > > Instead of pivoting on the returned PTE value, how about we return > > > -EAGAIN from the early return in stage2_attr_walker()? It would better > > > match the pattern used elsewhere in the pgtable code. > > > > That works, although I would use another return code (e.g., EINVAL)? as > > that's not exactly a "try again" type of error. > > EINVAL usually is an indication of something that went horribly wrong. > > But is that really a failure mode? Here, failing to update the PTE > should not be considered a failure, but just a benign race: access > fault being taken on a CPU and the page being evicted on another (not > unlikely, as the page was marked old before). I see, I agree, what you describe not look like a failure. > > And if I'm correct above, this is definitely a "try again" situation: > you probably won't take the same type of fault the second time though. > > Thanks, > > M. > > -- > Without deviation from the norm, progress is not possible. > ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
[PATCH v2 49/50] KVM: Opt out of generic hardware enabling on s390 and PPC
Allow architectures to opt out of the generic hardware enabling logic,
and opt out on both s390 and PPC, which don't need to manually enable
virtualization as it's always on (when available).
In addition to letting s390 and PPC drop a bit of dead code, this will
hopefully also allow ARM to clean up its related code, e.g. ARM has its
own per-CPU flag to track which CPUs have enable hardware due to the
need to keep hardware enabled indefinitely when pKVM is enabled.
Signed-off-by: Sean Christopherson
Acked-by: Anup Patel
---
arch/arm64/kvm/Kconfig | 1 +
arch/mips/kvm/Kconfig | 1 +
arch/powerpc/include/asm/kvm_host.h | 1 -
arch/powerpc/kvm/powerpc.c | 5 -
arch/riscv/kvm/Kconfig | 1 +
arch/s390/include/asm/kvm_host.h| 1 -
arch/s390/kvm/kvm-s390.c| 6 --
arch/x86/kvm/Kconfig| 1 +
include/linux/kvm_host.h| 4
virt/kvm/Kconfig| 3 +++
virt/kvm/kvm_main.c | 30 +++--
11 files changed, 35 insertions(+), 19 deletions(-)
diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig
index 815cc118c675..0a7d2116b27b 100644
--- a/arch/arm64/kvm/Kconfig
+++ b/arch/arm64/kvm/Kconfig
@@ -21,6 +21,7 @@ if VIRTUALIZATION
menuconfig KVM
bool "Kernel-based Virtual Machine (KVM) support"
depends on HAVE_KVM
+ select KVM_GENERIC_HARDWARE_ENABLING
select MMU_NOTIFIER
select PREEMPT_NOTIFIERS
select HAVE_KVM_CPU_RELAX_INTERCEPT
diff --git a/arch/mips/kvm/Kconfig b/arch/mips/kvm/Kconfig
index 91d197bee9c0..29e51649203b 100644
--- a/arch/mips/kvm/Kconfig
+++ b/arch/mips/kvm/Kconfig
@@ -28,6 +28,7 @@ config KVM
select MMU_NOTIFIER
select SRCU
select INTERVAL_TREE
+ select KVM_GENERIC_HARDWARE_ENABLING
help
Support for hosting Guest kernels.
diff --git a/arch/powerpc/include/asm/kvm_host.h
b/arch/powerpc/include/asm/kvm_host.h
index 0a80e80c7b9e..959f566a455c 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -876,7 +876,6 @@ struct kvm_vcpu_arch {
#define __KVM_HAVE_ARCH_WQP
#define __KVM_HAVE_CREATE_DEVICE
-static inline void kvm_arch_hardware_disable(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
static inline void kvm_arch_flush_shadow_all(struct kvm *kvm) {}
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index f5b4ff6bfc89..4c5405fc5538 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -435,11 +435,6 @@ int kvmppc_ld(struct kvm_vcpu *vcpu, ulong *eaddr, int
size, void *ptr,
}
EXPORT_SYMBOL_GPL(kvmppc_ld);
-int kvm_arch_hardware_enable(void)
-{
- return 0;
-}
-
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
struct kvmppc_ops *kvm_ops = NULL;
diff --git a/arch/riscv/kvm/Kconfig b/arch/riscv/kvm/Kconfig
index f36a737d5f96..d5a658a047a7 100644
--- a/arch/riscv/kvm/Kconfig
+++ b/arch/riscv/kvm/Kconfig
@@ -20,6 +20,7 @@ if VIRTUALIZATION
config KVM
tristate "Kernel-based Virtual Machine (KVM) support (EXPERIMENTAL)"
depends on RISCV_SBI && MMU
+ select KVM_GENERIC_HARDWARE_ENABLING
select MMU_NOTIFIER
select PREEMPT_NOTIFIERS
select KVM_MMIO
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index d67ce719d16a..2bbc3d54959d 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -1031,7 +1031,6 @@ extern char sie_exit;
extern int kvm_s390_gisc_register(struct kvm *kvm, u32 gisc);
extern int kvm_s390_gisc_unregister(struct kvm *kvm, u32 gisc);
-static inline void kvm_arch_hardware_disable(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
static inline void kvm_arch_free_memslot(struct kvm *kvm,
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 7ad8252e92c2..bd25076aa19b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -256,12 +256,6 @@ debug_info_t *kvm_s390_dbf;
debug_info_t *kvm_s390_dbf_uv;
/* Section: not file related */
-int kvm_arch_hardware_enable(void)
-{
- /* every s390 is virtualization enabled ;-) */
- return 0;
-}
-
/* forward declarations */
static void kvm_gmap_notifier(struct gmap *gmap, unsigned long start,
unsigned long end);
diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index fbeaa9ddef59..8e578311ca9d 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -49,6 +49,7 @@ config KVM
select SRCU
select INTERVAL_TREE
select HAVE_KVM_PM_NOTIFIER if PM
+ select KVM_GENERIC_HARDWARE_ENABLING
help
Support hosting fully virtualized guest machines using hardware
[PATCH v2 44/50] KVM: Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock
From: Isaku Yamahata
Drop kvm_count_lock and instead protect kvm_usage_count with kvm_lock now
that KVM hooks CPU hotplug during the ONLINE phase, which can sleep.
Previously, KVM hooked the STARTING phase, which is not allowed to sleep
and thus could not take kvm_lock (a mutex). This effectively allows the
task that's initiating hardware enabling/disabling to preempted and/or
migrated.
Note, the Documentation/virt/kvm/locking.rst statement that kvm_count_lock
is "raw" because hardware enabling/disabling needs to be atomic with
respect to migration is wrong on multiple fronts. First, while regular
spinlocks can be preempted, the task holding the lock cannot be migrated.
Second, preventing migration is not required. on_each_cpu() disables
preemption, which ensures that cpus_hardware_enabled correctly reflects
hardware state. The task may be preempted/migrated between bumping
kvm_usage_count and invoking on_each_cpu(), but that's perfectly ok as
kvm_usage_count is still protected, e.g. other tasks that call
hardware_enable_all() will be blocked until the preempted/migrated owner
exits its critical section.
KVM does have lockless accesses to kvm_usage_count in the suspend/resume
flows, but those are safe because all tasks must be frozen prior to
suspending CPUs, and a task cannot be frozen while it holds one or more
locks (userspace tasks are frozen via a fake signal).
Preemption doesn't need to be explicitly disabled in the hotplug path.
The hotplug thread is pinned to the CPU that's being hotplugged, and KVM
only cares about having a stable CPU, i.e. to ensure hardware is enabled
on the correct CPU. Lockep, i.e. check_preemption_disabled(), plays nice
with this state too, as is_percpu_thread() is true for the hotplug thread.
Signed-off-by: Isaku Yamahata
Co-developed-by: Sean Christopherson
Signed-off-by: Sean Christopherson
---
Documentation/virt/kvm/locking.rst | 19
virt/kvm/kvm_main.c| 36 --
2 files changed, 34 insertions(+), 21 deletions(-)
diff --git a/Documentation/virt/kvm/locking.rst
b/Documentation/virt/kvm/locking.rst
index 132a9e5436e5..cd570e565522 100644
--- a/Documentation/virt/kvm/locking.rst
+++ b/Documentation/virt/kvm/locking.rst
@@ -9,6 +9,8 @@ KVM Lock Overview
The acquisition orders for mutexes are as follows:
+- cpus_read_lock() is taken outside kvm_lock
+
- kvm->lock is taken outside vcpu->mutex
- kvm->lock is taken outside kvm->slots_lock and kvm->irq_lock
@@ -216,15 +218,10 @@ time it will be set using the Dirty tracking mechanism
described above.
:Type: mutex
:Arch: any
:Protects: - vm_list
-
-``kvm_count_lock``
-^^
-
-:Type: raw_spinlock_t
-:Arch: any
-:Protects: - hardware virtualization enable/disable
-:Comment: 'raw' because hardware enabling/disabling must be atomic /wrt
- migration.
+ - kvm_usage_count
+ - hardware virtualization enable/disable
+:Comment: KVM also disables CPU hotplug via cpus_read_lock() during
+ enable/disable.
``kvm->mn_invalidate_lock``
^^^
@@ -288,3 +285,7 @@ time it will be set using the Dirty tracking mechanism
described above.
:Type: mutex
:Arch: x86
:Protects: loading a vendor module (kvm_amd or kvm_intel)
+:Comment: Exists because using kvm_lock leads to deadlock.
cpu_hotplug_lock is
+taken outside of kvm_lock, e.g. in KVM's CPU online/offline callbacks, and
+many operations need to take cpu_hotplug_lock when loading a vendor module,
+e.g. updating static calls.
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index a46d61e9c053..6a8fb53b32f0 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -100,7 +100,6 @@ EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
*/
DEFINE_MUTEX(kvm_lock);
-static DEFINE_RAW_SPINLOCK(kvm_count_lock);
LIST_HEAD(vm_list);
static cpumask_var_t cpus_hardware_enabled;
@@ -5054,17 +5053,18 @@ static int kvm_online_cpu(unsigned int cpu)
* be enabled. Otherwise running VMs would encounter unrecoverable
* errors when scheduled to this CPU.
*/
- raw_spin_lock(_count_lock);
+ mutex_lock(_lock);
if (kvm_usage_count) {
WARN_ON_ONCE(atomic_read(_enable_failed));
hardware_enable_nolock(NULL);
+
if (atomic_read(_enable_failed)) {
atomic_set(_enable_failed, 0);
ret = -EIO;
}
}
- raw_spin_unlock(_count_lock);
+ mutex_unlock(_lock);
return ret;
}
@@ -5080,10 +5080,10 @@ static void hardware_disable_nolock(void *junk)
static int kvm_offline_cpu(unsigned int cpu)
{
- raw_spin_lock(_count_lock);
+ mutex_lock(_lock);
if (kvm_usage_count)
hardware_disable_nolock(NULL);
- raw_spin_unlock(_count_lock);
+
[PATCH v2 46/50] KVM: Use a per-CPU variable to track which CPUs have enabled virtualization
Use a per-CPU variable instead of a shared bitmap to track which CPUs
have successfully enabled virtualization hardware. Using a per-CPU bool
avoids the need for an additional allocation, and arguably yields easier
to read code. Using a bitmap would be advantageous if KVM used it to
avoid generating IPIs to CPUs that failed to enable hardware, but that's
an extreme edge case and not worth optimizing, and the low level helpers
would still want to keep their individual checks as attempting to enable
virtualization hardware when it's already enabled can be problematic,
e.g. Intel's VMXON will fault.
Opportunistically change the order in hardware_enable_nolock() to set
the flag if and only if hardware enabling is successful, instead of
speculatively setting the flag and then clearing it on failure.
Add a comment explaining that the check in hardware_disable_nolock()
isn't simply paranoia. Waaay back when, commit 1b6c016818a5 ("KVM: Keep
track of which cpus have virtualization enabled"), added the logic as a
guards against CPU hotplug racing with hardware enable/disable. Now that
KVM has eliminated the race by taking cpu_hotplug_lock for read (via
cpus_read_lock()) when enabling or disabling hardware, at first glance it
appears that the check is now superfluous, i.e. it's tempting to remove
the per-CPU flag entirely...
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 41 ++---
1 file changed, 18 insertions(+), 23 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index a27ded004644..c1e48c18e2d9 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -102,7 +102,7 @@ EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
DEFINE_MUTEX(kvm_lock);
LIST_HEAD(vm_list);
-static cpumask_var_t cpus_hardware_enabled;
+static DEFINE_PER_CPU(bool, hardware_enabled);
static int kvm_usage_count;
static atomic_t hardware_enable_failed;
@@ -5027,21 +5027,17 @@ static struct miscdevice kvm_dev = {
static void hardware_enable_nolock(void *junk)
{
- int cpu = smp_processor_id();
- int r;
-
- if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
+ if (__this_cpu_read(hardware_enabled))
return;
- cpumask_set_cpu(cpu, cpus_hardware_enabled);
-
- r = kvm_arch_hardware_enable();
-
- if (r) {
- cpumask_clear_cpu(cpu, cpus_hardware_enabled);
+ if (kvm_arch_hardware_enable()) {
atomic_inc(_enable_failed);
- pr_info("kvm: enabling virtualization on CPU%d failed\n", cpu);
+ pr_info("kvm: enabling virtualization on CPU%d failed\n",
+ raw_smp_processor_id());
+ return;
}
+
+ __this_cpu_write(hardware_enabled, true);
}
static int kvm_online_cpu(unsigned int cpu)
@@ -5070,12 +5066,16 @@ static int kvm_online_cpu(unsigned int cpu)
static void hardware_disable_nolock(void *junk)
{
- int cpu = smp_processor_id();
-
- if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
+ /*
+* Note, hardware_disable_all_nolock() tells all online CPUs to disable
+* hardware, not just CPUs that successfully enabled hardware!
+*/
+ if (!__this_cpu_read(hardware_enabled))
return;
- cpumask_clear_cpu(cpu, cpus_hardware_enabled);
+
kvm_arch_hardware_disable();
+
+ __this_cpu_write(hardware_enabled, false);
}
static int kvm_offline_cpu(unsigned int cpu)
@@ -5876,13 +5876,11 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
int r;
int cpu;
- if (!zalloc_cpumask_var(_hardware_enabled, GFP_KERNEL))
- return -ENOMEM;
-
r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online",
kvm_online_cpu, kvm_offline_cpu);
if (r)
- goto out_free_2;
+ return r;
+
register_reboot_notifier(_reboot_notifier);
/* A kmem cache lets us meet the alignment requirements of fx_save. */
@@ -5955,8 +5953,6 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
out_free_3:
unregister_reboot_notifier(_reboot_notifier);
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
-out_free_2:
- free_cpumask_var(cpus_hardware_enabled);
return r;
}
EXPORT_SYMBOL_GPL(kvm_init);
@@ -5982,7 +5978,6 @@ void kvm_exit(void)
unregister_reboot_notifier(_reboot_notifier);
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
kvm_irqfd_exit();
- free_cpumask_var(cpus_hardware_enabled);
}
EXPORT_SYMBOL_GPL(kvm_exit);
--
2.38.1.584.g0f3c55d4c2-goog
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[PATCH v2 50/50] KVM: Clean up error labels in kvm_init()
Convert the last two "out" lables to "err" labels now that the dust has
settled, i.e. now that there are no more planned changes to the order
of things in kvm_init().
Use "err" instead of "out" as it's easier to describe what failed than it
is to describe what needs to be unwound, e.g. if allocating a per-CPU kick
mask fails, KVM needs to free any masks that were allocated, and of course
needs to unwind previous operations.
Reported-by: Chao Gao
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 8
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 6a2be96557c2..b8c6bfb46066 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5907,14 +5907,14 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
NULL);
if (!kvm_vcpu_cache) {
r = -ENOMEM;
- goto out_free_3;
+ goto err_vcpu_cache;
}
for_each_possible_cpu(cpu) {
if (!alloc_cpumask_var_node(_cpu(cpu_kick_mask, cpu),
GFP_KERNEL, cpu_to_node(cpu))) {
r = -ENOMEM;
- goto out_free_4;
+ goto err_cpu_kick_mask;
}
}
@@ -5956,11 +5956,11 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
err_async_pf:
kvm_irqfd_exit();
err_irqfd:
-out_free_4:
+err_cpu_kick_mask:
for_each_possible_cpu(cpu)
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
kmem_cache_destroy(kvm_vcpu_cache);
-out_free_3:
+err_vcpu_cache:
#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING
unregister_syscore_ops(_syscore_ops);
unregister_reboot_notifier(_reboot_notifier);
--
2.38.1.584.g0f3c55d4c2-goog
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[PATCH v2 48/50] KVM: Register syscore (suspend/resume) ops early in kvm_init()
Register the suspend/resume notifier hooks at the same time KVM registers
its reboot notifier so that all the code in kvm_init() that deals with
enabling/disabling hardware is bundled together. Opportunstically move
KVM's implementations to reside near the reboot notifier code for the
same reason.
Bunching the code together will allow architectures to opt out of KVM's
generic hardware enable/disable logic with minimal #ifdeffery.
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 68 ++---
1 file changed, 34 insertions(+), 34 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 674a9dab5411..c12db3839114 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5154,6 +5154,38 @@ static struct notifier_block kvm_reboot_notifier = {
.priority = 0,
};
+static int kvm_suspend(void)
+{
+ /*
+* Secondary CPUs and CPU hotplug are disabled across the suspend/resume
+* callbacks, i.e. no need to acquire kvm_lock to ensure the usage count
+* is stable. Assert that kvm_lock is not held to ensure the system
+* isn't suspended while KVM is enabling hardware. Hardware enabling
+* can be preempted, but the task cannot be frozen until it has dropped
+* all locks (userspace tasks are frozen via a fake signal).
+*/
+ lockdep_assert_not_held(_lock);
+ lockdep_assert_irqs_disabled();
+
+ if (kvm_usage_count)
+ hardware_disable_nolock(NULL);
+ return 0;
+}
+
+static void kvm_resume(void)
+{
+ lockdep_assert_not_held(_lock);
+ lockdep_assert_irqs_disabled();
+
+ if (kvm_usage_count)
+ WARN_ON_ONCE(__hardware_enable_nolock());
+}
+
+static struct syscore_ops kvm_syscore_ops = {
+ .suspend = kvm_suspend,
+ .resume = kvm_resume,
+};
+
static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
{
int i;
@@ -5732,38 +5764,6 @@ static void kvm_init_debug(void)
}
}
-static int kvm_suspend(void)
-{
- /*
-* Secondary CPUs and CPU hotplug are disabled across the suspend/resume
-* callbacks, i.e. no need to acquire kvm_lock to ensure the usage count
-* is stable. Assert that kvm_lock is not held to ensure the system
-* isn't suspended while KVM is enabling hardware. Hardware enabling
-* can be preempted, but the task cannot be frozen until it has dropped
-* all locks (userspace tasks are frozen via a fake signal).
-*/
- lockdep_assert_not_held(_lock);
- lockdep_assert_irqs_disabled();
-
- if (kvm_usage_count)
- hardware_disable_nolock(NULL);
- return 0;
-}
-
-static void kvm_resume(void)
-{
- lockdep_assert_not_held(_lock);
- lockdep_assert_irqs_disabled();
-
- if (kvm_usage_count)
- WARN_ON_ONCE(__hardware_enable_nolock());
-}
-
-static struct syscore_ops kvm_syscore_ops = {
- .suspend = kvm_suspend,
- .resume = kvm_resume,
-};
-
static inline
struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
{
@@ -5879,6 +5879,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
return r;
register_reboot_notifier(_reboot_notifier);
+ register_syscore_ops(_syscore_ops);
/* A kmem cache lets us meet the alignment requirements of fx_save. */
if (!vcpu_align)
@@ -5913,8 +5914,6 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
kvm_chardev_ops.owner = module;
- register_syscore_ops(_syscore_ops);
-
kvm_preempt_ops.sched_in = kvm_sched_in;
kvm_preempt_ops.sched_out = kvm_sched_out;
@@ -5948,6 +5947,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
kmem_cache_destroy(kvm_vcpu_cache);
out_free_3:
+ unregister_syscore_ops(_syscore_ops);
unregister_reboot_notifier(_reboot_notifier);
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
return r;
--
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[PATCH v2 47/50] KVM: Make hardware_enable_failed a local variable in the "enable all" path
From: Isaku Yamahata
Rework detecting hardware enabling errors to use a local variable in the
"enable all" path to track whether or not enabling was successful across
all CPUs. Using a global variable complicates paths that enable hardware
only on the current CPU, e.g. kvm_resume() and kvm_online_cpu().
Opportunistically add a WARN if hardware enabling fails during
kvm_resume(), KVM is all kinds of hosed if CPU0 fails to enable hardware.
The WARN is largely futile in the current code, as KVM BUG()s on spurious
faults on VMX instructions, e.g. attempting to run a vCPU on CPU if
hardware enabling fails will explode.
[ cut here ]
kernel BUG at arch/x86/kvm/x86.c:508!
invalid opcode: [#1] SMP
CPU: 3 PID: 1009 Comm: CPU 4/KVM Not tainted 6.1.0-rc1+ #11
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:kvm_spurious_fault+0xa/0x10
Call Trace:
vmx_vcpu_load_vmcs+0x192/0x230 [kvm_intel]
vmx_vcpu_load+0x16/0x60 [kvm_intel]
kvm_arch_vcpu_load+0x32/0x1f0
vcpu_load+0x2f/0x40
kvm_arch_vcpu_ioctl_run+0x19/0x9d0
kvm_vcpu_ioctl+0x271/0x660
__x64_sys_ioctl+0x80/0xb0
do_syscall_64+0x2b/0x50
entry_SYSCALL_64_after_hwframe+0x46/0xb0
But, the WARN may provide a breadcrumb to understand what went awry, and
someday KVM may fix one or both of those bugs, e.g. by finding a way to
eat spurious faults no matter the context (easier said than done due to
side effects of certain operations, e.g. Intel's VMCLEAR).
Signed-off-by: Isaku Yamahata
[sean: rebase, WARN on failure in kvm_resume()]
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 35 ---
1 file changed, 16 insertions(+), 19 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index c1e48c18e2d9..674a9dab5411 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -104,7 +104,6 @@ LIST_HEAD(vm_list);
static DEFINE_PER_CPU(bool, hardware_enabled);
static int kvm_usage_count;
-static atomic_t hardware_enable_failed;
static struct kmem_cache *kvm_vcpu_cache;
@@ -5025,19 +5024,25 @@ static struct miscdevice kvm_dev = {
_chardev_ops,
};
-static void hardware_enable_nolock(void *junk)
+static int __hardware_enable_nolock(void)
{
if (__this_cpu_read(hardware_enabled))
- return;
+ return 0;
if (kvm_arch_hardware_enable()) {
- atomic_inc(_enable_failed);
pr_info("kvm: enabling virtualization on CPU%d failed\n",
raw_smp_processor_id());
- return;
+ return -EIO;
}
__this_cpu_write(hardware_enabled, true);
+ return 0;
+}
+
+static void hardware_enable_nolock(void *failed)
+{
+ if (__hardware_enable_nolock())
+ atomic_inc(failed);
}
static int kvm_online_cpu(unsigned int cpu)
@@ -5050,16 +5055,8 @@ static int kvm_online_cpu(unsigned int cpu)
* errors when scheduled to this CPU.
*/
mutex_lock(_lock);
- if (kvm_usage_count) {
- WARN_ON_ONCE(atomic_read(_enable_failed));
-
- hardware_enable_nolock(NULL);
-
- if (atomic_read(_enable_failed)) {
- atomic_set(_enable_failed, 0);
- ret = -EIO;
- }
- }
+ if (kvm_usage_count)
+ ret = __hardware_enable_nolock();
mutex_unlock(_lock);
return ret;
}
@@ -5107,6 +5104,7 @@ static void hardware_disable_all(void)
static int hardware_enable_all(void)
{
+ atomic_t failed = ATOMIC_INIT(0);
int r = 0;
/*
@@ -5122,10 +5120,9 @@ static int hardware_enable_all(void)
kvm_usage_count++;
if (kvm_usage_count == 1) {
- atomic_set(_enable_failed, 0);
- on_each_cpu(hardware_enable_nolock, NULL, 1);
+ on_each_cpu(hardware_enable_nolock, , 1);
- if (atomic_read(_enable_failed)) {
+ if (atomic_read()) {
hardware_disable_all_nolock();
r = -EBUSY;
}
@@ -5759,7 +5756,7 @@ static void kvm_resume(void)
lockdep_assert_irqs_disabled();
if (kvm_usage_count)
- hardware_enable_nolock(NULL);
+ WARN_ON_ONCE(__hardware_enable_nolock());
}
static struct syscore_ops kvm_syscore_ops = {
--
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[PATCH v2 45/50] KVM: Remove on_each_cpu(hardware_disable_nolock) in kvm_exit()
From: Isaku Yamahata Drop the superfluous invocation of hardware_disable_nolock() during kvm_exit(), as it's nothing more than a glorified nop. KVM automatically disables hardware on all CPUs when the last VM is destroyed, and kvm_exit() cannot be called until the last VM goes away as the calling module is pinned by an elevated refcount of the fops associated with /dev/kvm. This holds true even on x86, where the caller of kvm_exit() is not kvm.ko, but is instead a dependent module, kvm_amd.ko or kvm_intel.ko, as kvm_chardev_ops.owner is set to the module that calls kvm_init(), not hardcoded to the base kvm.ko module. Signed-off-by: Isaku Yamahata [sean: rework changelog] Signed-off-by: Sean Christopherson --- virt/kvm/kvm_main.c | 1 - 1 file changed, 1 deletion(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6a8fb53b32f0..a27ded004644 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -5981,7 +5981,6 @@ void kvm_exit(void) unregister_syscore_ops(_syscore_ops); unregister_reboot_notifier(_reboot_notifier); cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE); - on_each_cpu(hardware_disable_nolock, NULL, 1); kvm_irqfd_exit(); free_cpumask_var(cpus_hardware_enabled); } -- 2.38.1.584.g0f3c55d4c2-goog ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
[PATCH v2 43/50] KVM: Ensure CPU is stable during low level hardware enable/disable
Use the non-raw smp_processor_id() in the low hardware enable/disable
helpers as KVM absolutely relies on the CPU being stable, e.g. KVM would
end up with incorrect state if the task were migrated between accessing
cpus_hardware_enabled and actually enabling/disabling hardware.
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d985b24c423b..a46d61e9c053 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5028,7 +5028,7 @@ static struct miscdevice kvm_dev = {
static void hardware_enable_nolock(void *junk)
{
- int cpu = raw_smp_processor_id();
+ int cpu = smp_processor_id();
int r;
if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
@@ -5070,7 +5070,7 @@ static int kvm_online_cpu(unsigned int cpu)
static void hardware_disable_nolock(void *junk)
{
- int cpu = raw_smp_processor_id();
+ int cpu = smp_processor_id();
if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
return;
--
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[PATCH v2 41/50] KVM: Rename and move CPUHP_AP_KVM_STARTING to ONLINE section
From: Chao Gao
The CPU STARTING section doesn't allow callbacks to fail. Move KVM's
hotplug callback to ONLINE section so that it can abort onlining a CPU in
certain cases to avoid potentially breaking VMs running on existing CPUs.
For example, when KVM fails to enable hardware virtualization on the
hotplugged CPU.
Place KVM's hotplug state before CPUHP_AP_SCHED_WAIT_EMPTY as it ensures
when offlining a CPU, all user tasks and non-pinned kernel tasks have left
the CPU, i.e. there cannot be a vCPU task around. So, it is safe for KVM's
CPU offline callback to disable hardware virtualization at that point.
Likewise, KVM's online callback can enable hardware virtualization before
any vCPU task gets a chance to run on hotplugged CPUs.
Drop kvm_x86_check_processor_compatibility()'s WARN that IRQs are
disabled, as the ONLINE section runs with IRQs disabled. The WARN wasn't
intended to be a requirement, e.g. disabling preemption is sufficient,
the IRQ thing was purely an aggressive sanity check since the helper was
only ever invoked via SMP function call.
Rename KVM's CPU hotplug callbacks accordingly.
Suggested-by: Thomas Gleixner
Signed-off-by: Chao Gao
Signed-off-by: Isaku Yamahata
Reviewed-by: Yuan Yao
[sean: drop WARN that IRQs are disabled]
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/x86.c | 2 --
include/linux/cpuhotplug.h | 2 +-
virt/kvm/kvm_main.c| 30 ++
3 files changed, 23 insertions(+), 11 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5a9e74cedbc6..dad30097f0c3 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9283,8 +9283,6 @@ static int kvm_x86_check_processor_compatibility(void)
{
struct cpuinfo_x86 *c = _data(smp_processor_id());
- WARN_ON(!irqs_disabled());
-
if (__cr4_reserved_bits(cpu_has, c) !=
__cr4_reserved_bits(cpu_has, _cpu_data))
return -EIO;
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 7337414e4947..de45be38dd27 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -185,7 +185,6 @@ enum cpuhp_state {
CPUHP_AP_CSKY_TIMER_STARTING,
CPUHP_AP_TI_GP_TIMER_STARTING,
CPUHP_AP_HYPERV_TIMER_STARTING,
- CPUHP_AP_KVM_STARTING,
/* Must be the last timer callback */
CPUHP_AP_DUMMY_TIMER_STARTING,
CPUHP_AP_ARM_XEN_STARTING,
@@ -200,6 +199,7 @@ enum cpuhp_state {
/* Online section invoked on the hotplugged CPU from the hotplug thread
*/
CPUHP_AP_ONLINE_IDLE,
+ CPUHP_AP_KVM_ONLINE,
CPUHP_AP_SCHED_WAIT_EMPTY,
CPUHP_AP_SMPBOOT_THREADS,
CPUHP_AP_X86_VDSO_VMA_ONLINE,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 3900bd3d75cb..f26ea779710a 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5045,13 +5045,27 @@ static void hardware_enable_nolock(void *junk)
}
}
-static int kvm_starting_cpu(unsigned int cpu)
+static int kvm_online_cpu(unsigned int cpu)
{
+ int ret = 0;
+
+ /*
+* Abort the CPU online process if hardware virtualization cannot
+* be enabled. Otherwise running VMs would encounter unrecoverable
+* errors when scheduled to this CPU.
+*/
raw_spin_lock(_count_lock);
- if (kvm_usage_count)
+ if (kvm_usage_count) {
+ WARN_ON_ONCE(atomic_read(_enable_failed));
+
hardware_enable_nolock(NULL);
+ if (atomic_read(_enable_failed)) {
+ atomic_set(_enable_failed, 0);
+ ret = -EIO;
+ }
+ }
raw_spin_unlock(_count_lock);
- return 0;
+ return ret;
}
static void hardware_disable_nolock(void *junk)
@@ -5064,7 +5078,7 @@ static void hardware_disable_nolock(void *junk)
kvm_arch_hardware_disable();
}
-static int kvm_dying_cpu(unsigned int cpu)
+static int kvm_offline_cpu(unsigned int cpu)
{
raw_spin_lock(_count_lock);
if (kvm_usage_count)
@@ -5841,8 +5855,8 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
if (!zalloc_cpumask_var(_hardware_enabled, GFP_KERNEL))
return -ENOMEM;
- r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "kvm/cpu:starting",
- kvm_starting_cpu, kvm_dying_cpu);
+ r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online",
+ kvm_online_cpu, kvm_offline_cpu);
if (r)
goto out_free_2;
register_reboot_notifier(_reboot_notifier);
@@ -5916,7 +5930,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align,
struct module *module)
kmem_cache_destroy(kvm_vcpu_cache);
out_free_3:
unregister_reboot_notifier(_reboot_notifier);
- cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
+ cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
[PATCH v2 40/50] KVM: x86: Do compatibility checks when onlining CPU
From: Chao Gao
Do compatibility checks when enabling hardware to effectively add
compatibility checks when onlining a CPU. Abort enabling, i.e. the
online process, if the (hotplugged) CPU is incompatible with the known
good setup.
At init time, KVM does compatibility checks to ensure that all online
CPUs support hardware virtualization and a common set of features. But
KVM uses hotplugged CPUs without such compatibility checks. On Intel
CPUs, this leads to #GP if the hotplugged CPU doesn't support VMX, or
VM-Entry failure if the hotplugged CPU doesn't support all features
enabled by KVM.
Note, this is little more than a NOP on SVM, as SVM already checks for
full SVM support during hardware enabling.
Opportunistically add a pr_err() if setup_vmcs_config() fails, and
tweak all error messages to output which CPU failed.
Signed-off-by: Chao Gao
Co-developed-by: Sean Christopherson
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/svm/svm.c | 8 +++-
arch/x86/kvm/vmx/vmx.c | 15 ++-
arch/x86/kvm/x86.c | 5 +
3 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index c2e95c0d9fd8..46b658d0f46e 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -521,11 +521,12 @@ static void svm_init_osvw(struct kvm_vcpu *vcpu)
static bool kvm_is_svm_supported(void)
{
+ int cpu = raw_smp_processor_id();
const char *msg;
u64 vm_cr;
if (!cpu_has_svm()) {
- pr_err("SVM not supported, %s\n", msg);
+ pr_err("SVM not supported by CPU %d, %s\n", cpu, msg);
return false;
}
@@ -536,7 +537,7 @@ static bool kvm_is_svm_supported(void)
rdmsrl(MSR_VM_CR, vm_cr);
if (vm_cr & (1 << SVM_VM_CR_SVM_DISABLE)) {
- pr_err("SVM disabled (by BIOS) in MSR_VM_CR\n");
+ pr_err("SVM disabled (by BIOS) in MSR_VM_CR on CPU %d\n", cpu);
return false;
}
@@ -587,9 +588,6 @@ static int svm_hardware_enable(void)
if (efer & EFER_SVME)
return -EBUSY;
- if (!kvm_is_svm_supported())
- return -EINVAL;
-
sd = per_cpu_ptr(_data, me);
sd->asid_generation = 1;
sd->max_asid = cpuid_ebx(SVM_CPUID_FUNC) - 1;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 6416ed5b7f89..39dd3082fcd8 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2711,14 +2711,16 @@ static int setup_vmcs_config(struct vmcs_config
*vmcs_conf,
static bool kvm_is_vmx_supported(void)
{
+ int cpu = raw_smp_processor_id();
+
if (!cpu_has_vmx()) {
- pr_err("CPU doesn't support VMX\n");
+ pr_err("VMX not supported by CPU %d\n", cpu);
return false;
}
if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
!this_cpu_has(X86_FEATURE_VMX)) {
- pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL\n");
+ pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL on CPU
%d\n", cpu);
return false;
}
@@ -2727,18 +2729,21 @@ static bool kvm_is_vmx_supported(void)
static int vmx_check_processor_compat(void)
{
+ int cpu = raw_smp_processor_id();
struct vmcs_config vmcs_conf;
struct vmx_capability vmx_cap;
if (!kvm_is_vmx_supported())
return -EIO;
- if (setup_vmcs_config(_conf, _cap) < 0)
+ if (setup_vmcs_config(_conf, _cap) < 0) {
+ pr_err("Failed to setup VMCS config on CPU %d\n", cpu);
return -EIO;
+ }
if (nested)
nested_vmx_setup_ctls_msrs(_conf, vmx_cap.ept);
- if (memcmp(_config, _conf, sizeof(struct vmcs_config)) != 0) {
- pr_err("CPU %d feature inconsistency!\n", smp_processor_id());
+ if (memcmp(_config, _conf, sizeof(struct vmcs_config))) {
+ pr_err("Inconsistent VMCS config on CPU %d\n", cpu);
return -EIO;
}
return 0;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ee9af412ffd4..5a9e74cedbc6 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11967,6 +11967,11 @@ int kvm_arch_hardware_enable(void)
bool stable, backwards_tsc = false;
kvm_user_return_msr_cpu_online();
+
+ ret = kvm_x86_check_processor_compatibility();
+ if (ret)
+ return ret;
+
ret = static_call(kvm_x86_hardware_enable)();
if (ret != 0)
return ret;
--
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[PATCH v2 42/50] KVM: Disable CPU hotplug during hardware enabling/disabling
From: Chao Gao
Disable CPU hotplug when enabling/disabling hardware to prevent the
corner case where if the following sequence occurs:
1. A hotplugged CPU marks itself online in cpu_online_mask
2. The hotplugged CPU enables interrupt before invoking KVM's ONLINE
callback
3 hardware_{en,dis}able_all() is invoked on another CPU
the hotplugged CPU will be included in on_each_cpu() and thus get sent
through hardware_{en,dis}able_nolock() before kvm_online_cpu() is called.
start_secondary { ...
set_cpu_online(smp_processor_id(), true); <- 1
...
local_irq_enable(); <- 2
...
cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); <- 3
}
KVM currently fudges around this race by keeping track of which CPUs have
done hardware enabling (see commit 1b6c016818a5 "KVM: Keep track of which
cpus have virtualization enabled"), but that's an inefficient, convoluted,
and hacky solution.
Signed-off-by: Chao Gao
[sean: split to separate patch, write changelog]
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/x86.c | 11 ++-
virt/kvm/kvm_main.c | 12
2 files changed, 22 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index dad30097f0c3..d2ad383da998 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9281,7 +9281,16 @@ static inline void kvm_ops_update(struct
kvm_x86_init_ops *ops)
static int kvm_x86_check_processor_compatibility(void)
{
- struct cpuinfo_x86 *c = _data(smp_processor_id());
+ int cpu = smp_processor_id();
+ struct cpuinfo_x86 *c = _data(cpu);
+
+ /*
+* Compatibility checks are done when loading KVM and when enabling
+* hardware, e.g. during CPU hotplug, to ensure all online CPUs are
+* compatible, i.e. KVM should never perform a compatibility check on
+* an offline CPU.
+*/
+ WARN_ON(!cpu_online(cpu));
if (__cr4_reserved_bits(cpu_has, c) !=
__cr4_reserved_bits(cpu_has, _cpu_data))
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index f26ea779710a..d985b24c423b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5098,15 +5098,26 @@ static void hardware_disable_all_nolock(void)
static void hardware_disable_all(void)
{
+ cpus_read_lock();
raw_spin_lock(_count_lock);
hardware_disable_all_nolock();
raw_spin_unlock(_count_lock);
+ cpus_read_unlock();
}
static int hardware_enable_all(void)
{
int r = 0;
+ /*
+* When onlining a CPU, cpu_online_mask is set before kvm_online_cpu()
+* is called, and so on_each_cpu() between them includes the CPU that
+* is being onlined. As a result, hardware_enable_nolock() may get
+* invoked before kvm_online_cpu(), which also enables hardware if the
+* usage count is non-zero. Disable CPU hotplug to avoid attempting to
+* enable hardware multiple times.
+*/
+ cpus_read_lock();
raw_spin_lock(_count_lock);
kvm_usage_count++;
@@ -5121,6 +5132,7 @@ static int hardware_enable_all(void)
}
raw_spin_unlock(_count_lock);
+ cpus_read_unlock();
return r;
}
--
2.38.1.584.g0f3c55d4c2-goog
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[PATCH v2 37/50] KVM: VMX: Shuffle support checks and hardware enabling code around
Reorder code in vmx.c so that the VMX support check helpers reside above
the hardware enabling helpers, which will allow KVM to perform support
checks during hardware enabling (in a future patch).
No functional change intended.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/vmx/vmx.c | 216 -
1 file changed, 108 insertions(+), 108 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 23b64bf4bfcf..2a8a6e481c76 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2485,79 +2485,6 @@ static void vmx_cache_reg(struct kvm_vcpu *vcpu, enum
kvm_reg reg)
}
}
-static int kvm_cpu_vmxon(u64 vmxon_pointer)
-{
- u64 msr;
-
- cr4_set_bits(X86_CR4_VMXE);
-
- asm_volatile_goto("1: vmxon %[vmxon_pointer]\n\t"
- _ASM_EXTABLE(1b, %l[fault])
- : : [vmxon_pointer] "m"(vmxon_pointer)
- : : fault);
- return 0;
-
-fault:
- WARN_ONCE(1, "VMXON faulted, MSR_IA32_FEAT_CTL (0x3a) = 0x%llx\n",
- rdmsrl_safe(MSR_IA32_FEAT_CTL, ) ? 0xdeadbeef : msr);
- cr4_clear_bits(X86_CR4_VMXE);
-
- return -EFAULT;
-}
-
-static int vmx_hardware_enable(void)
-{
- int cpu = raw_smp_processor_id();
- u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
- int r;
-
- if (cr4_read_shadow() & X86_CR4_VMXE)
- return -EBUSY;
-
- /*
-* This can happen if we hot-added a CPU but failed to allocate
-* VP assist page for it.
-*/
- if (static_branch_unlikely(_evmcs) &&
- !hv_get_vp_assist_page(cpu))
- return -EFAULT;
-
- intel_pt_handle_vmx(1);
-
- r = kvm_cpu_vmxon(phys_addr);
- if (r) {
- intel_pt_handle_vmx(0);
- return r;
- }
-
- if (enable_ept)
- ept_sync_global();
-
- return 0;
-}
-
-static void vmclear_local_loaded_vmcss(void)
-{
- int cpu = raw_smp_processor_id();
- struct loaded_vmcs *v, *n;
-
- list_for_each_entry_safe(v, n, _cpu(loaded_vmcss_on_cpu, cpu),
-loaded_vmcss_on_cpu_link)
- __loaded_vmcs_clear(v);
-}
-
-static void vmx_hardware_disable(void)
-{
- vmclear_local_loaded_vmcss();
-
- if (cpu_vmxoff())
- kvm_spurious_fault();
-
- hv_reset_evmcs();
-
- intel_pt_handle_vmx(0);
-}
-
/*
* There is no X86_FEATURE for SGX yet, but anyway we need to query CPUID
* directly instead of going through cpu_has(), to ensure KVM is trapping
@@ -2783,6 +2710,114 @@ static __init int setup_vmcs_config(struct vmcs_config
*vmcs_conf,
return 0;
}
+static bool __init kvm_is_vmx_supported(void)
+{
+ if (!cpu_has_vmx()) {
+ pr_err("CPU doesn't support VMX\n");
+ return false;
+ }
+
+ if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
+ !this_cpu_has(X86_FEATURE_VMX)) {
+ pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL\n");
+ return false;
+ }
+
+ return true;
+}
+
+static int __init vmx_check_processor_compat(void)
+{
+ struct vmcs_config vmcs_conf;
+ struct vmx_capability vmx_cap;
+
+ if (!kvm_is_vmx_supported())
+ return -EIO;
+
+ if (setup_vmcs_config(_conf, _cap) < 0)
+ return -EIO;
+ if (nested)
+ nested_vmx_setup_ctls_msrs(_conf, vmx_cap.ept);
+ if (memcmp(_config, _conf, sizeof(struct vmcs_config)) != 0) {
+ pr_err("CPU %d feature inconsistency!\n", smp_processor_id());
+ return -EIO;
+ }
+ return 0;
+}
+
+static int kvm_cpu_vmxon(u64 vmxon_pointer)
+{
+ u64 msr;
+
+ cr4_set_bits(X86_CR4_VMXE);
+
+ asm_volatile_goto("1: vmxon %[vmxon_pointer]\n\t"
+ _ASM_EXTABLE(1b, %l[fault])
+ : : [vmxon_pointer] "m"(vmxon_pointer)
+ : : fault);
+ return 0;
+
+fault:
+ WARN_ONCE(1, "VMXON faulted, MSR_IA32_FEAT_CTL (0x3a) = 0x%llx\n",
+ rdmsrl_safe(MSR_IA32_FEAT_CTL, ) ? 0xdeadbeef : msr);
+ cr4_clear_bits(X86_CR4_VMXE);
+
+ return -EFAULT;
+}
+
+static int vmx_hardware_enable(void)
+{
+ int cpu = raw_smp_processor_id();
+ u64 phys_addr = __pa(per_cpu(vmxarea, cpu));
+ int r;
+
+ if (cr4_read_shadow() & X86_CR4_VMXE)
+ return -EBUSY;
+
+ /*
+* This can happen if we hot-added a CPU but failed to allocate
+* VP assist page for it.
+*/
+ if (static_branch_unlikely(_evmcs) &&
+ !hv_get_vp_assist_page(cpu))
+ return -EFAULT;
+
+ intel_pt_handle_vmx(1);
+
+ r = kvm_cpu_vmxon(phys_addr);
+ if (r) {
+ intel_pt_handle_vmx(0);
+ return r;
+ }
+
+ if (enable_ept)
+
[PATCH v2 39/50] KVM: x86: Move CPU compat checks hook to kvm_x86_ops (from kvm_x86_init_ops)
Move the .check_processor_compatibility() callback from kvm_x86_init_ops
to kvm_x86_ops to allow a future patch to do compatibility checks during
CPU hotplug.
Do kvm_ops_update() before compat checks so that static_call() can be
used during compat checks.
Signed-off-by: Sean Christopherson
---
arch/x86/include/asm/kvm-x86-ops.h | 1 +
arch/x86/include/asm/kvm_host.h| 3 ++-
arch/x86/kvm/svm/svm.c | 5 +++--
arch/x86/kvm/vmx/vmx.c | 16 +++
arch/x86/kvm/x86.c | 31 +++---
5 files changed, 25 insertions(+), 31 deletions(-)
diff --git a/arch/x86/include/asm/kvm-x86-ops.h
b/arch/x86/include/asm/kvm-x86-ops.h
index abccd51dcfca..dba2909e5ae2 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -14,6 +14,7 @@ BUILD_BUG_ON(1)
* to make a definition optional, but in this case the default will
* be __static_call_return0.
*/
+KVM_X86_OP(check_processor_compatibility)
KVM_X86_OP(hardware_enable)
KVM_X86_OP(hardware_disable)
KVM_X86_OP(hardware_unsetup)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d79aedf70908..ba74fea6850b 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1518,6 +1518,8 @@ static inline u16 kvm_lapic_irq_dest_mode(bool
dest_mode_logical)
struct kvm_x86_ops {
const char *name;
+ int (*check_processor_compatibility)(void);
+
int (*hardware_enable)(void);
void (*hardware_disable)(void);
void (*hardware_unsetup)(void);
@@ -1729,7 +1731,6 @@ struct kvm_x86_nested_ops {
};
struct kvm_x86_init_ops {
- int (*check_processor_compatibility)(void);
int (*hardware_setup)(void);
unsigned int (*handle_intel_pt_intr)(void);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 9f94efcb9aa6..c2e95c0d9fd8 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -543,7 +543,7 @@ static bool kvm_is_svm_supported(void)
return true;
}
-static int __init svm_check_processor_compat(void)
+static int svm_check_processor_compat(void)
{
if (!kvm_is_svm_supported())
return -EIO;
@@ -4695,6 +4695,8 @@ static int svm_vm_init(struct kvm *kvm)
static struct kvm_x86_ops svm_x86_ops __initdata = {
.name = KBUILD_MODNAME,
+ .check_processor_compatibility = svm_check_processor_compat,
+
.hardware_unsetup = svm_hardware_unsetup,
.hardware_enable = svm_hardware_enable,
.hardware_disable = svm_hardware_disable,
@@ -5079,7 +5081,6 @@ static __init int svm_hardware_setup(void)
static struct kvm_x86_init_ops svm_init_ops __initdata = {
.hardware_setup = svm_hardware_setup,
- .check_processor_compatibility = svm_check_processor_compat,
.runtime_ops = _x86_ops,
.pmu_ops = _pmu_ops,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 2a8a6e481c76..6416ed5b7f89 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2520,8 +2520,7 @@ static bool cpu_has_perf_global_ctrl_bug(void)
return false;
}
-static __init int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt,
- u32 msr, u32 *result)
+static int adjust_vmx_controls(u32 ctl_min, u32 ctl_opt, u32 msr, u32 *result)
{
u32 vmx_msr_low, vmx_msr_high;
u32 ctl = ctl_min | ctl_opt;
@@ -2539,7 +2538,7 @@ static __init int adjust_vmx_controls(u32 ctl_min, u32
ctl_opt,
return 0;
}
-static __init u64 adjust_vmx_controls64(u64 ctl_opt, u32 msr)
+static u64 adjust_vmx_controls64(u64 ctl_opt, u32 msr)
{
u64 allowed;
@@ -2548,8 +2547,8 @@ static __init u64 adjust_vmx_controls64(u64 ctl_opt, u32
msr)
return ctl_opt & allowed;
}
-static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf,
- struct vmx_capability *vmx_cap)
+static int setup_vmcs_config(struct vmcs_config *vmcs_conf,
+struct vmx_capability *vmx_cap)
{
u32 vmx_msr_low, vmx_msr_high;
u32 _pin_based_exec_control = 0;
@@ -2710,7 +2709,7 @@ static __init int setup_vmcs_config(struct vmcs_config
*vmcs_conf,
return 0;
}
-static bool __init kvm_is_vmx_supported(void)
+static bool kvm_is_vmx_supported(void)
{
if (!cpu_has_vmx()) {
pr_err("CPU doesn't support VMX\n");
@@ -2726,7 +2725,7 @@ static bool __init kvm_is_vmx_supported(void)
return true;
}
-static int __init vmx_check_processor_compat(void)
+static int vmx_check_processor_compat(void)
{
struct vmcs_config vmcs_conf;
struct vmx_capability vmx_cap;
@@ -8104,6 +8103,8 @@ static void vmx_vm_destroy(struct kvm *kvm)
static struct kvm_x86_ops vmx_x86_ops __initdata = {
.name = KBUILD_MODNAME,
+ .check_processor_compatibility = vmx_check_processor_compat,
+
.hardware_unsetup =
[PATCH v2 35/50] KVM: VMX: Use current CPU's info to perform "disabled by BIOS?" checks
Use this_cpu_has() instead of boot_cpu_has() to perform the effective
"disabled by BIOS?" checks for VMX. This will allow consolidating code
between vmx_disabled_by_bios() and vmx_check_processor_compat().
Checking the boot CPU isn't a strict requirement as any divergence in VMX
enabling between the boot CPU and other CPUs will result in KVM refusing
to load thanks to the aforementioned vmx_check_processor_compat().
Furthermore, using the boot CPU was an unintentional change introduced by
commit a4d0b2fdbcf7 ("KVM: VMX: Use VMX feature flag to query BIOS
enabling"). Prior to using the feature flags, KVM checked the raw MSR
value from the current CPU.
Reported-by: Kai Huang
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/vmx/vmx.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index e859d2b7daa4..3f7d9f88b314 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2492,8 +2492,8 @@ static __init int cpu_has_kvm_support(void)
static __init int vmx_disabled_by_bios(void)
{
- return !boot_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
- !boot_cpu_has(X86_FEATURE_VMX);
+ return !this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
+ !this_cpu_has(X86_FEATURE_VMX);
}
static int kvm_cpu_vmxon(u64 vmxon_pointer)
--
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[PATCH v2 38/50] KVM: SVM: Check for SVM support in CPU compatibility checks
Check that SVM is supported and enabled in the processor compatibility
checks. SVM already checks for support during hardware enabling,
i.e. this doesn't really add new functionality. The net effect is that
KVM will refuse to load if a CPU doesn't have SVM fully enabled, as
opposed to failing KVM_CREATE_VM.
Opportunistically move svm_check_processor_compat() up in svm.c so that
it can be invoked during hardware enabling in a future patch.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/svm/svm.c | 13 -
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 49ccef9fae81..9f94efcb9aa6 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -543,6 +543,14 @@ static bool kvm_is_svm_supported(void)
return true;
}
+static int __init svm_check_processor_compat(void)
+{
+ if (!kvm_is_svm_supported())
+ return -EIO;
+
+ return 0;
+}
+
void __svm_write_tsc_multiplier(u64 multiplier)
{
preempt_disable();
@@ -4087,11 +4095,6 @@ svm_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char
*hypercall)
hypercall[2] = 0xd9;
}
-static int __init svm_check_processor_compat(void)
-{
- return 0;
-}
-
/*
* The kvm parameter can be NULL (module initialization, or invocation before
* VM creation). Be sure to check the kvm parameter before using it.
--
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[PATCH v2 34/50] KVM: x86: Unify pr_fmt to use module name for all KVM modules
Define pr_fmt using KBUILD_MODNAME for all KVM x86 code so that printks
use consistent formatting across common x86, Intel, and AMD code. In
addition to providing consistent print formatting, using KBUILD_MODNAME,
e.g. kvm_amd and kvm_intel, allows referencing SVM and VMX (and SEV and
SGX and ...) as technologies without generating weird messages, and
without causing naming conflicts with other kernel code, e.g. "SEV: ",
"tdx: ", "sgx: " etc.. are all used by the kernel for non-KVM subsystems.
Opportunistically move away from printk() for prints that need to be
modified anyways, e.g. to drop a manual "kvm: " prefix.
Opportunistically convert a few SGX WARNs that are similarly modified to
WARN_ONCE; in the very unlikely event that the WARNs fire, odds are good
that they would fire repeatedly and spam the kernel log without providing
unique information in each print.
Note, defining pr_fmt yields undesirable results for code that uses KVM's
printk wrappers, e.g. vcpu_unimpl(). But, that's a pre-existing problem
as SVM/kvm_amd already defines a pr_fmt, and thankfully use of KVM's
wrappers is relatively limited in KVM x86 code.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/cpuid.c| 1 +
arch/x86/kvm/debugfs.c | 2 ++
arch/x86/kvm/emulate.c | 1 +
arch/x86/kvm/hyperv.c | 1 +
arch/x86/kvm/i8254.c| 4 ++--
arch/x86/kvm/i8259.c| 4 +++-
arch/x86/kvm/ioapic.c | 1 +
arch/x86/kvm/irq.c | 1 +
arch/x86/kvm/irq_comm.c | 7 +++---
arch/x86/kvm/kvm_onhyperv.c | 1 +
arch/x86/kvm/lapic.c| 8 +++
arch/x86/kvm/mmu/mmu.c | 6 ++---
arch/x86/kvm/mmu/page_track.c | 1 +
arch/x86/kvm/mmu/spte.c | 4 ++--
arch/x86/kvm/mmu/spte.h | 4 ++--
arch/x86/kvm/mmu/tdp_iter.c | 1 +
arch/x86/kvm/mmu/tdp_mmu.c | 1 +
arch/x86/kvm/mtrr.c | 1 +
arch/x86/kvm/pmu.c | 1 +
arch/x86/kvm/smm.c | 1 +
arch/x86/kvm/svm/avic.c | 2 +-
arch/x86/kvm/svm/nested.c | 2 +-
arch/x86/kvm/svm/pmu.c | 2 ++
arch/x86/kvm/svm/sev.c | 1 +
arch/x86/kvm/svm/svm.c | 10 -
arch/x86/kvm/svm/svm_onhyperv.c | 1 +
arch/x86/kvm/svm/svm_onhyperv.h | 4 ++--
arch/x86/kvm/vmx/hyperv.c | 1 +
arch/x86/kvm/vmx/hyperv.h | 4 +---
arch/x86/kvm/vmx/nested.c | 3 ++-
arch/x86/kvm/vmx/pmu_intel.c| 5 +++--
arch/x86/kvm/vmx/posted_intr.c | 2 ++
arch/x86/kvm/vmx/sgx.c | 5 +++--
arch/x86/kvm/vmx/vmcs12.c | 1 +
arch/x86/kvm/vmx/vmx.c | 40 -
arch/x86/kvm/vmx/vmx_ops.h | 4 ++--
arch/x86/kvm/x86.c | 28 ---
arch/x86/kvm/xen.c | 1 +
38 files changed, 97 insertions(+), 70 deletions(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 723502181a3a..82411693e604 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -8,6 +8,7 @@
* Copyright 2011 Red Hat, Inc. and/or its affiliates.
* Copyright IBM Corporation, 2008
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include
#include
diff --git a/arch/x86/kvm/debugfs.c b/arch/x86/kvm/debugfs.c
index c1390357126a..ee8c4c3496ed 100644
--- a/arch/x86/kvm/debugfs.c
+++ b/arch/x86/kvm/debugfs.c
@@ -4,6 +4,8 @@
*
* Copyright 2016 Red Hat, Inc. and/or its affiliates.
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include
#include
#include "lapic.h"
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 5cc3efa0e21c..c3443045cd93 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -17,6 +17,7 @@
*
* From: xen-unstable 10676:af9809f51f81a3c43f276f00c81a52ef558afda4
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include
#include "kvm_cache_regs.h"
diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 2c7f2a26421e..4c47892d72bb 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -17,6 +17,7 @@
* Ben-Ami Yassour
* Andrey Smetanin
*/
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include "x86.h"
#include "lapic.h"
diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c
index e0a7a0e7a73c..cd57a517d04a 100644
--- a/arch/x86/kvm/i8254.c
+++ b/arch/x86/kvm/i8254.c
@@ -30,7 +30,7 @@
* Based on QEMU and Xen.
*/
-#define pr_fmt(fmt) "pit: " fmt
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include
#include
@@ -351,7 +351,7 @@ static void create_pit_timer(struct kvm_pit *pit, u32 val,
int is_period)
if (ps->period < min_period) {
pr_info_ratelimited(
- "kvm: requested %lld ns "
+ "requested %lld ns "
"i8254 timer period limited to %lld ns\n",
ps->period, min_period);
ps->period = min_period;
diff --git a/arch/x86/kvm/i8259.c
[PATCH v2 36/50] KVM: x86: Do VMX/SVM support checks directly in vendor code
Do basic VMX/SVM support checks directly in vendor code instead of
implementing them via kvm_x86_ops hooks. Beyond the superficial benefit
of providing common messages, which isn't even clearly a net positive
since vendor code can provide more precise/detailed messages, there's
zero advantage to bouncing through common x86 code.
Consolidating the checks will also simplify performing the checks
across all CPUs (in a future patch).
Signed-off-by: Sean Christopherson
---
arch/x86/include/asm/kvm_host.h | 2 --
arch/x86/kvm/svm/svm.c | 38 +++--
arch/x86/kvm/vmx/vmx.c | 37 +---
arch/x86/kvm/x86.c | 11 --
4 files changed, 37 insertions(+), 51 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 04a9ae66fb8d..d79aedf70908 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1729,8 +1729,6 @@ struct kvm_x86_nested_ops {
};
struct kvm_x86_init_ops {
- int (*cpu_has_kvm_support)(void);
- int (*disabled_by_bios)(void);
int (*check_processor_compatibility)(void);
int (*hardware_setup)(void);
unsigned int (*handle_intel_pt_intr)(void);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index ab53da3fbcd1..49ccef9fae81 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -519,21 +519,28 @@ static void svm_init_osvw(struct kvm_vcpu *vcpu)
vcpu->arch.osvw.status |= 1;
}
-static int has_svm(void)
+static bool kvm_is_svm_supported(void)
{
const char *msg;
+ u64 vm_cr;
if (!cpu_has_svm()) {
- printk(KERN_INFO "has_svm: %s\n", msg);
- return 0;
+ pr_err("SVM not supported, %s\n", msg);
+ return false;
}
if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) {
pr_info("KVM is unsupported when running as an SEV guest\n");
- return 0;
+ return false;
}
- return 1;
+ rdmsrl(MSR_VM_CR, vm_cr);
+ if (vm_cr & (1 << SVM_VM_CR_SVM_DISABLE)) {
+ pr_err("SVM disabled (by BIOS) in MSR_VM_CR\n");
+ return false;
+ }
+
+ return true;
}
void __svm_write_tsc_multiplier(u64 multiplier)
@@ -572,10 +579,9 @@ static int svm_hardware_enable(void)
if (efer & EFER_SVME)
return -EBUSY;
- if (!has_svm()) {
- pr_err("%s: err EOPNOTSUPP on %d\n", __func__, me);
+ if (!kvm_is_svm_supported())
return -EINVAL;
- }
+
sd = per_cpu_ptr(_data, me);
sd->asid_generation = 1;
sd->max_asid = cpuid_ebx(SVM_CPUID_FUNC) - 1;
@@ -4070,17 +4076,6 @@ static void svm_load_mmu_pgd(struct kvm_vcpu *vcpu,
hpa_t root_hpa,
vmcb_mark_dirty(svm->vmcb, VMCB_CR);
}
-static int is_disabled(void)
-{
- u64 vm_cr;
-
- rdmsrl(MSR_VM_CR, vm_cr);
- if (vm_cr & (1 << SVM_VM_CR_SVM_DISABLE))
- return 1;
-
- return 0;
-}
-
static void
svm_patch_hypercall(struct kvm_vcpu *vcpu, unsigned char *hypercall)
{
@@ -5080,8 +5075,6 @@ static __init int svm_hardware_setup(void)
static struct kvm_x86_init_ops svm_init_ops __initdata = {
- .cpu_has_kvm_support = has_svm,
- .disabled_by_bios = is_disabled,
.hardware_setup = svm_hardware_setup,
.check_processor_compatibility = svm_check_processor_compat,
@@ -5095,6 +5088,9 @@ static int __init svm_init(void)
__unused_size_checks();
+ if (!kvm_is_svm_supported())
+ return -EOPNOTSUPP;
+
r = kvm_x86_vendor_init(_init_ops);
if (r)
return r;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 3f7d9f88b314..23b64bf4bfcf 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2485,17 +2485,6 @@ static void vmx_cache_reg(struct kvm_vcpu *vcpu, enum
kvm_reg reg)
}
}
-static __init int cpu_has_kvm_support(void)
-{
- return cpu_has_vmx();
-}
-
-static __init int vmx_disabled_by_bios(void)
-{
- return !this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
- !this_cpu_has(X86_FEATURE_VMX);
-}
-
static int kvm_cpu_vmxon(u64 vmxon_pointer)
{
u64 msr;
@@ -7479,16 +7468,29 @@ static int vmx_vm_init(struct kvm *kvm)
return 0;
}
+static bool __init kvm_is_vmx_supported(void)
+{
+ if (!cpu_has_vmx()) {
+ pr_err("CPU doesn't support VMX\n");
+ return false;
+ }
+
+ if (!this_cpu_has(X86_FEATURE_MSR_IA32_FEAT_CTL) ||
+ !this_cpu_has(X86_FEATURE_VMX)) {
+ pr_err("VMX not enabled (by BIOS) in MSR_IA32_FEAT_CTL\n");
+ return false;
+ }
+
+ return true;
+}
+
static int __init vmx_check_processor_compat(void)
{
struct vmcs_config vmcs_conf;
struct vmx_capability vmx_cap;
-
[PATCH v2 31/50] KVM: x86: Do CPU compatibility checks in x86 code
Move the CPU compatibility checks to pure x86 code, i.e. drop x86's use
of the common kvm_x86_check_cpu_compat() arch hook. x86 is the only
architecture that "needs" to do per-CPU compatibility checks, moving
the logic to x86 will allow dropping the common code, and will also
give x86 more control over when/how the compatibility checks are
performed, e.g. TDX will need to enable hardware (do VMXON) in order to
perform compatibility checks.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/svm/svm.c | 2 +-
arch/x86/kvm/vmx/vmx.c | 2 +-
arch/x86/kvm/x86.c | 49 --
3 files changed, 40 insertions(+), 13 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 19e81a99c58f..d7ea1c1175c2 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5103,7 +5103,7 @@ static int __init svm_init(void)
* Common KVM initialization _must_ come last, after this, /dev/kvm is
* exposed to userspace!
*/
- r = kvm_init(_init_ops, sizeof(struct vcpu_svm),
+ r = kvm_init(NULL, sizeof(struct vcpu_svm),
__alignof__(struct vcpu_svm), THIS_MODULE);
if (r)
goto err_kvm_init;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 654d81f781da..8deb1bd60c10 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8592,7 +8592,7 @@ static int __init vmx_init(void)
* Common KVM initialization _must_ come last, after this, /dev/kvm is
* exposed to userspace!
*/
- r = kvm_init(_init_ops, sizeof(struct vcpu_vmx),
+ r = kvm_init(NULL, sizeof(struct vcpu_vmx),
__alignof__(struct vcpu_vmx), THIS_MODULE);
if (r)
goto err_kvm_init;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 66f16458aa97..3571bc968cf8 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9277,10 +9277,36 @@ static inline void kvm_ops_update(struct
kvm_x86_init_ops *ops)
kvm_pmu_ops_update(ops->pmu_ops);
}
+struct kvm_cpu_compat_check {
+ struct kvm_x86_init_ops *ops;
+ int *ret;
+};
+
+static int kvm_x86_check_processor_compatibility(struct kvm_x86_init_ops *ops)
+{
+ struct cpuinfo_x86 *c = _data(smp_processor_id());
+
+ WARN_ON(!irqs_disabled());
+
+ if (__cr4_reserved_bits(cpu_has, c) !=
+ __cr4_reserved_bits(cpu_has, _cpu_data))
+ return -EIO;
+
+ return ops->check_processor_compatibility();
+}
+
+static void kvm_x86_check_cpu_compat(void *data)
+{
+ struct kvm_cpu_compat_check *c = data;
+
+ *c->ret = kvm_x86_check_processor_compatibility(c->ops);
+}
+
static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
{
+ struct kvm_cpu_compat_check c;
u64 host_pat;
- int r;
+ int r, cpu;
if (kvm_x86_ops.hardware_enable) {
pr_err("kvm: already loaded vendor module '%s'\n",
kvm_x86_ops.name);
@@ -9360,6 +9386,14 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops
*ops)
if (r != 0)
goto out_mmu_exit;
+ c.ret =
+ c.ops = ops;
+ for_each_online_cpu(cpu) {
+ smp_call_function_single(cpu, kvm_x86_check_cpu_compat, , 1);
+ if (r < 0)
+ goto out_hardware_unsetup;
+ }
+
/*
* Point of no return! DO NOT add error paths below this point unless
* absolutely necessary, as most operations from this point forward
@@ -9402,6 +9436,8 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops
*ops)
kvm_init_msr_list();
return 0;
+out_hardware_unsetup:
+ ops->runtime_ops->hardware_unsetup();
out_mmu_exit:
kvm_mmu_vendor_module_exit();
out_free_percpu:
@@ -12037,16 +12073,7 @@ void kvm_arch_hardware_disable(void)
int kvm_arch_check_processor_compat(void *opaque)
{
- struct cpuinfo_x86 *c = _data(smp_processor_id());
- struct kvm_x86_init_ops *ops = opaque;
-
- WARN_ON(!irqs_disabled());
-
- if (__cr4_reserved_bits(cpu_has, c) !=
- __cr4_reserved_bits(cpu_has, _cpu_data))
- return -EIO;
-
- return ops->check_processor_compatibility();
+ return 0;
}
bool kvm_vcpu_is_reset_bsp(struct kvm_vcpu *vcpu)
--
2.38.1.584.g0f3c55d4c2-goog
___
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[PATCH v2 28/50] KVM: s390: Mark __kvm_s390_init() and its descendants as __init
Tag __kvm_s390_init() and its unique helpers as __init. These functions
are only ever called during module_init(), but could not be tagged
accordingly while they were invoked from the common kvm_arch_init(),
which is not __init because of x86.
Signed-off-by: Sean Christopherson
Reviewed-by: Eric Farman
---
arch/s390/kvm/interrupt.c | 2 +-
arch/s390/kvm/kvm-s390.c | 4 ++--
arch/s390/kvm/kvm-s390.h | 2 +-
arch/s390/kvm/pci.c | 2 +-
arch/s390/kvm/pci.h | 2 +-
5 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index 1dae78deddf2..3754d7937530 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -3411,7 +3411,7 @@ void kvm_s390_gib_destroy(void)
gib = NULL;
}
-int kvm_s390_gib_init(u8 nisc)
+int __init kvm_s390_gib_init(u8 nisc)
{
int rc = 0;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 8c4fcaf2bd36..66d162723d21 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -366,7 +366,7 @@ static __always_inline void __insn32_query(unsigned int
opcode, u8 *query)
#define INSN_SORTL 0xb938
#define INSN_DFLTCC 0xb939
-static void kvm_s390_cpu_feat_init(void)
+static void __init kvm_s390_cpu_feat_init(void)
{
int i;
@@ -469,7 +469,7 @@ static void kvm_s390_cpu_feat_init(void)
*/
}
-static int __kvm_s390_init(void)
+static int __init __kvm_s390_init(void)
{
int rc = -ENOMEM;
diff --git a/arch/s390/kvm/kvm-s390.h b/arch/s390/kvm/kvm-s390.h
index d48588c207d8..0261d42c7d01 100644
--- a/arch/s390/kvm/kvm-s390.h
+++ b/arch/s390/kvm/kvm-s390.h
@@ -470,7 +470,7 @@ void kvm_s390_gisa_clear(struct kvm *kvm);
void kvm_s390_gisa_destroy(struct kvm *kvm);
void kvm_s390_gisa_disable(struct kvm *kvm);
void kvm_s390_gisa_enable(struct kvm *kvm);
-int kvm_s390_gib_init(u8 nisc);
+int __init kvm_s390_gib_init(u8 nisc);
void kvm_s390_gib_destroy(void);
/* implemented in guestdbg.c */
diff --git a/arch/s390/kvm/pci.c b/arch/s390/kvm/pci.c
index ded1af2ddae9..39544c92ce3d 100644
--- a/arch/s390/kvm/pci.c
+++ b/arch/s390/kvm/pci.c
@@ -670,7 +670,7 @@ int kvm_s390_pci_zpci_op(struct kvm *kvm, struct
kvm_s390_zpci_op *args)
return r;
}
-int kvm_s390_pci_init(void)
+int __init kvm_s390_pci_init(void)
{
zpci_kvm_hook.kvm_register = kvm_s390_pci_register_kvm;
zpci_kvm_hook.kvm_unregister = kvm_s390_pci_unregister_kvm;
diff --git a/arch/s390/kvm/pci.h b/arch/s390/kvm/pci.h
index 486d06ef563f..ff0972dd5e71 100644
--- a/arch/s390/kvm/pci.h
+++ b/arch/s390/kvm/pci.h
@@ -60,7 +60,7 @@ void kvm_s390_pci_clear_list(struct kvm *kvm);
int kvm_s390_pci_zpci_op(struct kvm *kvm, struct kvm_s390_zpci_op *args);
-int kvm_s390_pci_init(void);
+int __init kvm_s390_pci_init(void);
void kvm_s390_pci_exit(void);
static inline bool kvm_s390_pci_interp_allowed(void)
--
2.38.1.584.g0f3c55d4c2-goog
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[PATCH v2 32/50] KVM: Drop kvm_arch_check_processor_compat() hook
Drop kvm_arch_check_processor_compat() and its support code now that all
architecture implementations are nops.
Signed-off-by: Sean Christopherson
Reviewed-by: Philippe Mathieu-Daudé
Reviewed-by: Eric Farman # s390
Acked-by: Anup Patel
---
arch/arm64/kvm/arm.c | 7 +--
arch/mips/kvm/mips.c | 7 +--
arch/powerpc/kvm/book3s.c | 2 +-
arch/powerpc/kvm/e500.c| 2 +-
arch/powerpc/kvm/e500mc.c | 2 +-
arch/powerpc/kvm/powerpc.c | 5 -
arch/riscv/kvm/main.c | 7 +--
arch/s390/kvm/kvm-s390.c | 7 +--
arch/x86/kvm/svm/svm.c | 4 ++--
arch/x86/kvm/vmx/vmx.c | 4 ++--
arch/x86/kvm/x86.c | 5 -
include/linux/kvm_host.h | 4 +---
virt/kvm/kvm_main.c| 24 +---
13 files changed, 13 insertions(+), 67 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 936ef7d1ea94..e915b1d9f2cd 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -63,11 +63,6 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
}
-int kvm_arch_check_processor_compat(void *opaque)
-{
- return 0;
-}
-
int kvm_vm_ioctl_enable_cap(struct kvm *kvm,
struct kvm_enable_cap *cap)
{
@@ -2273,7 +2268,7 @@ static __init int kvm_arm_init(void)
* FIXME: Do something reasonable if kvm_init() fails after pKVM
* hypervisor protection is finalized.
*/
- err = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ err = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
if (err)
goto out_subs;
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 3cade648827a..36c8991b5d39 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -135,11 +135,6 @@ void kvm_arch_hardware_disable(void)
kvm_mips_callbacks->hardware_disable();
}
-int kvm_arch_check_processor_compat(void *opaque)
-{
- return 0;
-}
-
extern void kvm_init_loongson_ipi(struct kvm *kvm);
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
@@ -1636,7 +1631,7 @@ static int __init kvm_mips_init(void)
register_die_notifier(_mips_csr_die_notifier);
- ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ ret = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
if (ret) {
unregister_die_notifier(_mips_csr_die_notifier);
return ret;
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 87283a0e33d8..57f4e7896d67 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -1052,7 +1052,7 @@ static int kvmppc_book3s_init(void)
{
int r;
- r = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ r = kvm_init(sizeof(struct kvm_vcpu), 0, THIS_MODULE);
if (r)
return r;
#ifdef CONFIG_KVM_BOOK3S_32_HANDLER
diff --git a/arch/powerpc/kvm/e500.c b/arch/powerpc/kvm/e500.c
index 0ea61190ec04..b0f695428733 100644
--- a/arch/powerpc/kvm/e500.c
+++ b/arch/powerpc/kvm/e500.c
@@ -531,7 +531,7 @@ static int __init kvmppc_e500_init(void)
flush_icache_range(kvmppc_booke_handlers, kvmppc_booke_handlers +
ivor[max_ivor] + handler_len);
- r = kvm_init(NULL, sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
+ r = kvm_init(sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
if (r)
goto err_out;
kvm_ops_e500.owner = THIS_MODULE;
diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
index 795667f7ebf0..611532a0dedc 100644
--- a/arch/powerpc/kvm/e500mc.c
+++ b/arch/powerpc/kvm/e500mc.c
@@ -404,7 +404,7 @@ static int __init kvmppc_e500mc_init(void)
*/
kvmppc_init_lpid(KVMPPC_NR_LPIDS/threads_per_core);
- r = kvm_init(NULL, sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
+ r = kvm_init(sizeof(struct kvmppc_vcpu_e500), 0, THIS_MODULE);
if (r)
goto err_out;
kvm_ops_e500mc.owner = THIS_MODULE;
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 01d0f9935e6c..f5b4ff6bfc89 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -440,11 +440,6 @@ int kvm_arch_hardware_enable(void)
return 0;
}
-int kvm_arch_check_processor_compat(void *opaque)
-{
- return 0;
-}
-
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
{
struct kvmppc_ops *kvm_ops = NULL;
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index 4710a6751687..34c3dece6990 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -20,11 +20,6 @@ long kvm_arch_dev_ioctl(struct file *filp,
return -EINVAL;
}
-int kvm_arch_check_processor_compat(void *opaque)
-{
- return 0;
-}
-
int kvm_arch_hardware_enable(void)
{
unsigned long hideleg, hedeleg;
@@ -110,6 +105,6 @@ static int __init riscv_kvm_init(void)
[PATCH v2 33/50] KVM: x86: Use KBUILD_MODNAME to specify vendor module name
Use KBUILD_MODNAME to specify the vendor module name instead of manually
writing out the name to make it a bit more obvious that the name isn't
completely arbitrary. A future patch will also use KBUILD_MODNAME to
define pr_fmt, at which point using KBUILD_MODNAME for kvm_x86_ops.name
further reinforces the intended usage of kvm_x86_ops.name.
No functional change intended.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/svm/svm.c | 2 +-
arch/x86/kvm/vmx/vmx.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index d9a54590591d..a875cf7b2942 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4695,7 +4695,7 @@ static int svm_vm_init(struct kvm *kvm)
}
static struct kvm_x86_ops svm_x86_ops __initdata = {
- .name = "kvm_amd",
+ .name = KBUILD_MODNAME,
.hardware_unsetup = svm_hardware_unsetup,
.hardware_enable = svm_hardware_enable,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b6f08a0a1435..229a9cf485f0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8102,7 +8102,7 @@ static void vmx_vm_destroy(struct kvm *kvm)
}
static struct kvm_x86_ops vmx_x86_ops __initdata = {
- .name = "kvm_intel",
+ .name = KBUILD_MODNAME,
.hardware_unsetup = vmx_hardware_unsetup,
--
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[PATCH v2 30/50] KVM: VMX: Make VMCS configuration/capabilities structs read-only after init
Tag vmcs_config and vmx_capability structs as __init, the canonical
configuration is generated during hardware_setup() and must never be
modified after that point.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/vmx/capabilities.h | 4 ++--
arch/x86/kvm/vmx/vmx.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/x86/kvm/vmx/capabilities.h b/arch/x86/kvm/vmx/capabilities.h
index cd2ac9536c99..45162c1bcd8f 100644
--- a/arch/x86/kvm/vmx/capabilities.h
+++ b/arch/x86/kvm/vmx/capabilities.h
@@ -66,13 +66,13 @@ struct vmcs_config {
u64 misc;
struct nested_vmx_msrs nested;
};
-extern struct vmcs_config vmcs_config;
+extern struct vmcs_config vmcs_config __ro_after_init;
struct vmx_capability {
u32 ept;
u32 vpid;
};
-extern struct vmx_capability vmx_capability;
+extern struct vmx_capability vmx_capability __ro_after_init;
static inline bool cpu_has_vmx_basic_inout(void)
{
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 76185a7a7ded..654d81f781da 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -488,8 +488,8 @@ static DEFINE_PER_CPU(struct list_head,
loaded_vmcss_on_cpu);
static DECLARE_BITMAP(vmx_vpid_bitmap, VMX_NR_VPIDS);
static DEFINE_SPINLOCK(vmx_vpid_lock);
-struct vmcs_config vmcs_config;
-struct vmx_capability vmx_capability;
+struct vmcs_config vmcs_config __ro_after_init;
+struct vmx_capability vmx_capability __ro_after_init;
#define VMX_SEGMENT_FIELD(seg) \
[VCPU_SREG_##seg] = { \
--
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[PATCH v2 29/50] KVM: Drop kvm_arch_{init,exit}() hooks
Drop kvm_arch_init() and kvm_arch_exit() now that all implementations
are nops.
No functional change intended.
Signed-off-by: Sean Christopherson
Reviewed-by: Eric Farman # s390
Reviewed-by: Philippe Mathieu-Daudé
Acked-by: Anup Patel
---
arch/arm64/kvm/arm.c| 11 ---
arch/mips/kvm/mips.c| 10 --
arch/powerpc/include/asm/kvm_host.h | 1 -
arch/powerpc/kvm/powerpc.c | 5 -
arch/riscv/kvm/main.c | 9 -
arch/s390/kvm/kvm-s390.c| 10 --
arch/x86/kvm/x86.c | 10 --
include/linux/kvm_host.h| 3 ---
virt/kvm/kvm_main.c | 19 ++-
9 files changed, 2 insertions(+), 76 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 4d34abcfc9a9..936ef7d1ea94 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -2289,17 +2289,6 @@ static __init int kvm_arm_init(void)
return err;
}
-int kvm_arch_init(void *opaque)
-{
- return 0;
-}
-
-/* NOP: Compiling as a module not supported */
-void kvm_arch_exit(void)
-{
-
-}
-
static int __init early_kvm_mode_cfg(char *arg)
{
if (!arg)
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index ae7a24342fdf..3cade648827a 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -1010,16 +1010,6 @@ long kvm_arch_vm_ioctl(struct file *filp, unsigned int
ioctl, unsigned long arg)
return r;
}
-int kvm_arch_init(void *opaque)
-{
- return 0;
-}
-
-void kvm_arch_exit(void)
-{
-
-}
-
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
struct kvm_sregs *sregs)
{
diff --git a/arch/powerpc/include/asm/kvm_host.h
b/arch/powerpc/include/asm/kvm_host.h
index 5d2c3a487e73..0a80e80c7b9e 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -881,7 +881,6 @@ static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
static inline void kvm_arch_flush_shadow_all(struct kvm *kvm) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
-static inline void kvm_arch_exit(void) {}
static inline void kvm_arch_vcpu_blocking(struct kvm_vcpu *vcpu) {}
static inline void kvm_arch_vcpu_unblocking(struct kvm_vcpu *vcpu) {}
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index d44b85ba8cef..01d0f9935e6c 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -2539,11 +2539,6 @@ void kvmppc_init_lpid(unsigned long nr_lpids_param)
}
EXPORT_SYMBOL_GPL(kvmppc_init_lpid);
-int kvm_arch_init(void *opaque)
-{
- return 0;
-}
-
EXPORT_TRACEPOINT_SYMBOL_GPL(kvm_ppc_instr);
void kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu, struct dentry
*debugfs_dentry)
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index cb063b8a9a0f..4710a6751687 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -65,15 +65,6 @@ void kvm_arch_hardware_disable(void)
csr_write(CSR_HIDELEG, 0);
}
-int kvm_arch_init(void *opaque)
-{
- return 0;
-}
-
-void kvm_arch_exit(void)
-{
-}
-
static int __init riscv_kvm_init(void)
{
const char *str;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 66d162723d21..25b08b956888 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -541,16 +541,6 @@ static void __kvm_s390_exit(void)
debug_unregister(kvm_s390_dbf_uv);
}
-int kvm_arch_init(void *opaque)
-{
- return 0;
-}
-
-void kvm_arch_exit(void)
-{
-
-}
-
/* Section: device related */
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 45184ca89317..66f16458aa97 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9277,16 +9277,6 @@ static inline void kvm_ops_update(struct
kvm_x86_init_ops *ops)
kvm_pmu_ops_update(ops->pmu_ops);
}
-int kvm_arch_init(void *opaque)
-{
- return 0;
-}
-
-void kvm_arch_exit(void)
-{
-
-}
-
static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
{
u64 host_pat;
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index f2e0e78d2d92..7dde28333e7c 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -1439,9 +1439,6 @@ int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu
*vcpu,
struct kvm_guest_debug *dbg);
int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu);
-int kvm_arch_init(void *opaque);
-void kvm_arch_exit(void);
-
void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu);
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0e62887e8ce1..a4a10a0b322f 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5852,20 +5852,8 @@ int
[PATCH v2 24/50] KVM: RISC-V: Do arch init directly in riscv_kvm_init()
Fold the guts of kvm_arch_init() into riscv_kvm_init() instead of
bouncing through kvm_init()=>kvm_arch_init(). Functionally, this is a
glorified nop as invoking kvm_arch_init() is the very first action
performed by kvm_init().
Moving setup to riscv_kvm_init(), which is tagged __init, will allow
tagging more functions and data with __init and __ro_after_init. And
emptying kvm_arch_init() will allow dropping the hook entirely once all
architecture implementations are nops.
No functional change intended.
Signed-off-by: Sean Christopherson
Reviewed-by: Philippe Mathieu-Daudé
Acked-by: Anup Patel
---
arch/riscv/kvm/main.c | 18 +-
1 file changed, 9 insertions(+), 9 deletions(-)
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index a146fa0ce4d2..cb063b8a9a0f 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -66,6 +66,15 @@ void kvm_arch_hardware_disable(void)
}
int kvm_arch_init(void *opaque)
+{
+ return 0;
+}
+
+void kvm_arch_exit(void)
+{
+}
+
+static int __init riscv_kvm_init(void)
{
const char *str;
@@ -110,15 +119,6 @@ int kvm_arch_init(void *opaque)
kvm_info("VMID %ld bits available\n", kvm_riscv_gstage_vmid_bits());
- return 0;
-}
-
-void kvm_arch_exit(void)
-{
-}
-
-static int __init riscv_kvm_init(void)
-{
return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
}
module_init(riscv_kvm_init);
--
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[PATCH v2 27/50] KVM: s390: Do s390 specific init without bouncing through kvm_init()
Move the guts of kvm_arch_init() into a new helper, __kvm_s390_init(),
and invoke the new helper directly from kvm_s390_init() instead of
bouncing through kvm_init(). Invoking kvm_arch_init() is the very
first action performed by kvm_init(), i.e. this is a glorified nop.
Moving setup to __kvm_s390_init() will allow tagging more functions as
__init, and emptying kvm_arch_init() will allow dropping the hook
entirely once all architecture implementations are nops.
No functional change intended.
Signed-off-by: Sean Christopherson
Reviewed-by: Eric Farman
Reviewed-by: Philippe Mathieu-Daudé
---
arch/s390/kvm/kvm-s390.c | 29 +
1 file changed, 25 insertions(+), 4 deletions(-)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 829e6e046003..8c4fcaf2bd36 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -469,7 +469,7 @@ static void kvm_s390_cpu_feat_init(void)
*/
}
-int kvm_arch_init(void *opaque)
+static int __kvm_s390_init(void)
{
int rc = -ENOMEM;
@@ -527,7 +527,7 @@ int kvm_arch_init(void *opaque)
return rc;
}
-void kvm_arch_exit(void)
+static void __kvm_s390_exit(void)
{
gmap_unregister_pte_notifier(_notifier);
gmap_unregister_pte_notifier(_gmap_notifier);
@@ -541,6 +541,16 @@ void kvm_arch_exit(void)
debug_unregister(kvm_s390_dbf_uv);
}
+int kvm_arch_init(void *opaque)
+{
+ return 0;
+}
+
+void kvm_arch_exit(void)
+{
+
+}
+
/* Section: device related */
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
@@ -5696,7 +5706,7 @@ static inline unsigned long nonhyp_mask(int i)
static int __init kvm_s390_init(void)
{
- int i;
+ int i, r;
if (!sclp.has_sief2) {
pr_info("SIE is not available\n");
@@ -5712,12 +5722,23 @@ static int __init kvm_s390_init(void)
kvm_s390_fac_base[i] |=
stfle_fac_list[i] & nonhyp_mask(i);
- return kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ r = __kvm_s390_init();
+ if (r)
+ return r;
+
+ r = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ if (r) {
+ __kvm_s390_exit();
+ return r;
+ }
+ return 0;
}
static void __exit kvm_s390_exit(void)
{
kvm_exit();
+
+ __kvm_s390_exit();
}
module_init(kvm_s390_init);
--
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[PATCH v2 26/50] KVM: PPC: Move processor compatibility check to module init
Move KVM PPC's compatibility checks to their respective module_init()
hooks, there's no need to wait until KVM's common compat check, nor is
there a need to perform the check on every CPU (provided by common KVM's
hook), as the compatibility checks operate on global data.
arch/powerpc/include/asm/cputable.h: extern struct cpu_spec *cur_cpu_spec;
arch/powerpc/kvm/book3s.c: return 0
arch/powerpc/kvm/e500.c: strcmp(cur_cpu_spec->cpu_name, "e500v2")
arch/powerpc/kvm/e500mc.c: strcmp(cur_cpu_spec->cpu_name, "e500mc")
strcmp(cur_cpu_spec->cpu_name, "e5500")
strcmp(cur_cpu_spec->cpu_name, "e6500")
Cc: Fabiano Rosas
Cc: Michael Ellerman
Signed-off-by: Sean Christopherson
---
arch/powerpc/include/asm/kvm_ppc.h | 1 -
arch/powerpc/kvm/book3s.c | 10 --
arch/powerpc/kvm/e500.c| 4 ++--
arch/powerpc/kvm/e500mc.c | 4
arch/powerpc/kvm/powerpc.c | 2 +-
5 files changed, 7 insertions(+), 14 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_ppc.h
b/arch/powerpc/include/asm/kvm_ppc.h
index bfacf12784dd..51a1824b0a16 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -118,7 +118,6 @@ extern int kvmppc_xlate(struct kvm_vcpu *vcpu, ulong eaddr,
extern int kvmppc_core_vcpu_create(struct kvm_vcpu *vcpu);
extern void kvmppc_core_vcpu_free(struct kvm_vcpu *vcpu);
extern int kvmppc_core_vcpu_setup(struct kvm_vcpu *vcpu);
-extern int kvmppc_core_check_processor_compat(void);
extern int kvmppc_core_vcpu_translate(struct kvm_vcpu *vcpu,
struct kvm_translation *tr);
diff --git a/arch/powerpc/kvm/book3s.c b/arch/powerpc/kvm/book3s.c
index 6d525285dbe8..87283a0e33d8 100644
--- a/arch/powerpc/kvm/book3s.c
+++ b/arch/powerpc/kvm/book3s.c
@@ -999,16 +999,6 @@ int kvmppc_h_logical_ci_store(struct kvm_vcpu *vcpu)
}
EXPORT_SYMBOL_GPL(kvmppc_h_logical_ci_store);
-int kvmppc_core_check_processor_compat(void)
-{
- /*
-* We always return 0 for book3s. We check
-* for compatibility while loading the HV
-* or PR module
-*/
- return 0;
-}
-
int kvmppc_book3s_hcall_implemented(struct kvm *kvm, unsigned long hcall)
{
return kvm->arch.kvm_ops->hcall_implemented(hcall);
diff --git a/arch/powerpc/kvm/e500.c b/arch/powerpc/kvm/e500.c
index c8b2b4478545..0ea61190ec04 100644
--- a/arch/powerpc/kvm/e500.c
+++ b/arch/powerpc/kvm/e500.c
@@ -314,7 +314,7 @@ static void kvmppc_core_vcpu_put_e500(struct kvm_vcpu *vcpu)
kvmppc_booke_vcpu_put(vcpu);
}
-int kvmppc_core_check_processor_compat(void)
+static int kvmppc_e500_check_processor_compat(void)
{
int r;
@@ -507,7 +507,7 @@ static int __init kvmppc_e500_init(void)
unsigned long handler_len;
unsigned long max_ivor = 0;
- r = kvmppc_core_check_processor_compat();
+ r = kvmppc_e500_check_processor_compat();
if (r)
goto err_out;
diff --git a/arch/powerpc/kvm/e500mc.c b/arch/powerpc/kvm/e500mc.c
index 57e0ad6a2ca3..795667f7ebf0 100644
--- a/arch/powerpc/kvm/e500mc.c
+++ b/arch/powerpc/kvm/e500mc.c
@@ -388,6 +388,10 @@ static int __init kvmppc_e500mc_init(void)
{
int r;
+ r = kvmppc_e500mc_check_processor_compat();
+ if (r)
+ return kvmppc_e500mc;
+
r = kvmppc_booke_init();
if (r)
goto err_out;
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 5faf69421f13..d44b85ba8cef 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -442,7 +442,7 @@ int kvm_arch_hardware_enable(void)
int kvm_arch_check_processor_compat(void *opaque)
{
- return kvmppc_core_check_processor_compat();
+ return 0;
}
int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
--
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[PATCH v2 25/50] KVM: RISC-V: Tag init functions and data with __init, __ro_after_init
Now that KVM setup is handled directly in riscv_kvm_init(), tag functions
and data that are used/set only during init with __init/__ro_after_init.
Signed-off-by: Sean Christopherson
Acked-by: Anup Patel
---
arch/riscv/include/asm/kvm_host.h | 6 +++---
arch/riscv/kvm/mmu.c | 12 ++--
arch/riscv/kvm/vmid.c | 4 ++--
3 files changed, 11 insertions(+), 11 deletions(-)
diff --git a/arch/riscv/include/asm/kvm_host.h
b/arch/riscv/include/asm/kvm_host.h
index 8c771fc4f5d2..778ff0f282b7 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -295,11 +295,11 @@ int kvm_riscv_gstage_map(struct kvm_vcpu *vcpu,
int kvm_riscv_gstage_alloc_pgd(struct kvm *kvm);
void kvm_riscv_gstage_free_pgd(struct kvm *kvm);
void kvm_riscv_gstage_update_hgatp(struct kvm_vcpu *vcpu);
-void kvm_riscv_gstage_mode_detect(void);
-unsigned long kvm_riscv_gstage_mode(void);
+void __init kvm_riscv_gstage_mode_detect(void);
+unsigned long __init kvm_riscv_gstage_mode(void);
int kvm_riscv_gstage_gpa_bits(void);
-void kvm_riscv_gstage_vmid_detect(void);
+void __init kvm_riscv_gstage_vmid_detect(void);
unsigned long kvm_riscv_gstage_vmid_bits(void);
int kvm_riscv_gstage_vmid_init(struct kvm *kvm);
bool kvm_riscv_gstage_vmid_ver_changed(struct kvm_vmid *vmid);
diff --git a/arch/riscv/kvm/mmu.c b/arch/riscv/kvm/mmu.c
index 3620ecac2fa1..f42a34c7879a 100644
--- a/arch/riscv/kvm/mmu.c
+++ b/arch/riscv/kvm/mmu.c
@@ -20,12 +20,12 @@
#include
#ifdef CONFIG_64BIT
-static unsigned long gstage_mode = (HGATP_MODE_SV39X4 << HGATP_MODE_SHIFT);
-static unsigned long gstage_pgd_levels = 3;
+static unsigned long gstage_mode __ro_after_init = (HGATP_MODE_SV39X4 <<
HGATP_MODE_SHIFT);
+static unsigned long gstage_pgd_levels __ro_after_init = 3;
#define gstage_index_bits 9
#else
-static unsigned long gstage_mode = (HGATP_MODE_SV32X4 << HGATP_MODE_SHIFT);
-static unsigned long gstage_pgd_levels = 2;
+static unsigned long gstage_mode __ro_after_init = (HGATP_MODE_SV32X4 <<
HGATP_MODE_SHIFT);
+static unsigned long gstage_pgd_levels __ro_after_init = 2;
#define gstage_index_bits 10
#endif
@@ -760,7 +760,7 @@ void kvm_riscv_gstage_update_hgatp(struct kvm_vcpu *vcpu)
kvm_riscv_local_hfence_gvma_all();
}
-void kvm_riscv_gstage_mode_detect(void)
+void __init kvm_riscv_gstage_mode_detect(void)
{
#ifdef CONFIG_64BIT
/* Try Sv57x4 G-stage mode */
@@ -784,7 +784,7 @@ void kvm_riscv_gstage_mode_detect(void)
#endif
}
-unsigned long kvm_riscv_gstage_mode(void)
+unsigned long __init kvm_riscv_gstage_mode(void)
{
return gstage_mode >> HGATP_MODE_SHIFT;
}
diff --git a/arch/riscv/kvm/vmid.c b/arch/riscv/kvm/vmid.c
index 6cd93995fb65..5246da1c9167 100644
--- a/arch/riscv/kvm/vmid.c
+++ b/arch/riscv/kvm/vmid.c
@@ -17,10 +17,10 @@
static unsigned long vmid_version = 1;
static unsigned long vmid_next;
-static unsigned long vmid_bits;
+static unsigned long vmid_bits __ro_after_init;
static DEFINE_SPINLOCK(vmid_lock);
-void kvm_riscv_gstage_vmid_detect(void)
+void __init kvm_riscv_gstage_vmid_detect(void)
{
unsigned long old;
--
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[PATCH v2 23/50] KVM: MIPS: Register die notifier prior to kvm_init()
Call kvm_init() only after _all_ setup is complete, as kvm_init() exposes
/dev/kvm to userspace and thus allows userspace to create VMs (and call
other ioctls).
Signed-off-by: Sean Christopherson
Reviewed-by: Philippe Mathieu-Daudé
---
arch/mips/kvm/mips.c | 9 +
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 75681281e2df..ae7a24342fdf 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -1640,16 +1640,17 @@ static int __init kvm_mips_init(void)
if (ret)
return ret;
- ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
-
- if (ret)
- return ret;
if (boot_cpu_type() == CPU_LOONGSON64)
kvm_priority_to_irq = kvm_loongson3_priority_to_irq;
register_die_notifier(_mips_csr_die_notifier);
+ ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ if (ret) {
+ unregister_die_notifier(_mips_csr_die_notifier);
+ return ret;
+ }
return 0;
}
--
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[PATCH v2 20/50] KVM: arm64: Mark kvm_arm_init() and its unique descendants as __init
Tag kvm_arm_init() and its unique helper as __init, and tag data that is
only ever modified under the kvm_arm_init() umbrella as read-only after
init.
Opportunistically name the boolean param in kvm_timer_hyp_init()'s
prototype to match its definition.
Signed-off-by: Sean Christopherson
---
arch/arm64/include/asm/kvm_host.h | 14 ++---
arch/arm64/include/asm/kvm_mmu.h | 4 ++--
arch/arm64/kvm/arch_timer.c | 2 +-
arch/arm64/kvm/arm.c | 34 +++
arch/arm64/kvm/mmu.c | 12 +--
arch/arm64/kvm/reset.c| 8
arch/arm64/kvm/sys_regs.c | 6 +++---
arch/arm64/kvm/vmid.c | 6 +++---
include/kvm/arm_arch_timer.h | 2 +-
9 files changed, 44 insertions(+), 44 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h
b/arch/arm64/include/asm/kvm_host.h
index 5d5a887e63a5..4863fe356be1 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -66,8 +66,8 @@ enum kvm_mode kvm_get_mode(void);
DECLARE_STATIC_KEY_FALSE(userspace_irqchip_in_use);
-extern unsigned int kvm_sve_max_vl;
-int kvm_arm_init_sve(void);
+extern unsigned int __ro_after_init kvm_sve_max_vl;
+int __init kvm_arm_init_sve(void);
u32 __attribute_const__ kvm_target_cpu(void);
int kvm_reset_vcpu(struct kvm_vcpu *vcpu);
@@ -793,7 +793,7 @@ int kvm_handle_cp10_id(struct kvm_vcpu *vcpu);
void kvm_reset_sys_regs(struct kvm_vcpu *vcpu);
-int kvm_sys_reg_table_init(void);
+int __init kvm_sys_reg_table_init(void);
/* MMIO helpers */
void kvm_mmio_write_buf(void *buf, unsigned int len, unsigned long data);
@@ -824,9 +824,9 @@ int kvm_arm_pvtime_get_attr(struct kvm_vcpu *vcpu,
int kvm_arm_pvtime_has_attr(struct kvm_vcpu *vcpu,
struct kvm_device_attr *attr);
-extern unsigned int kvm_arm_vmid_bits;
-int kvm_arm_vmid_alloc_init(void);
-void kvm_arm_vmid_alloc_free(void);
+extern unsigned int __ro_after_init kvm_arm_vmid_bits;
+int __init kvm_arm_vmid_alloc_init(void);
+void __init kvm_arm_vmid_alloc_free(void);
void kvm_arm_vmid_update(struct kvm_vmid *kvm_vmid);
void kvm_arm_vmid_clear_active(void);
@@ -909,7 +909,7 @@ static inline void kvm_clr_pmu_events(u32 clr) {}
void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu);
void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu);
-int kvm_set_ipa_limit(void);
+int __init kvm_set_ipa_limit(void);
#define __KVM_HAVE_ARCH_VM_ALLOC
struct kvm *kvm_arch_alloc_vm(void);
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index 7784081088e7..ced5b0028933 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -163,7 +163,7 @@ int create_hyp_io_mappings(phys_addr_t phys_addr, size_t
size,
void __iomem **haddr);
int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size,
void **haddr);
-void free_hyp_pgds(void);
+void __init free_hyp_pgds(void);
void stage2_unmap_vm(struct kvm *kvm);
int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu);
@@ -175,7 +175,7 @@ int kvm_handle_guest_abort(struct kvm_vcpu *vcpu);
phys_addr_t kvm_mmu_get_httbr(void);
phys_addr_t kvm_get_idmap_vector(void);
-int kvm_mmu_init(u32 *hyp_va_bits);
+int __init kvm_mmu_init(u32 *hyp_va_bits);
static inline void *__kvm_vector_slot2addr(void *base,
enum arm64_hyp_spectre_vector slot)
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index 33fca1a691a5..23346585a294 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -1113,7 +1113,7 @@ static int kvm_irq_init(struct arch_timer_kvm_info *info)
return 0;
}
-int kvm_timer_hyp_init(bool has_gic)
+int __init kvm_timer_hyp_init(bool has_gic)
{
struct arch_timer_kvm_info *info;
int err;
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index d3a4db1abf32..4d34abcfc9a9 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1513,7 +1513,7 @@ static int kvm_init_vector_slots(void)
return 0;
}
-static void cpu_prepare_hyp_mode(int cpu)
+static void __init cpu_prepare_hyp_mode(int cpu)
{
struct kvm_nvhe_init_params *params =
per_cpu_ptr_nvhe_sym(kvm_init_params, cpu);
unsigned long tcr;
@@ -1739,26 +1739,26 @@ static struct notifier_block hyp_init_cpu_pm_nb = {
.notifier_call = hyp_init_cpu_pm_notifier,
};
-static void hyp_cpu_pm_init(void)
+static void __init hyp_cpu_pm_init(void)
{
if (!is_protected_kvm_enabled())
cpu_pm_register_notifier(_init_cpu_pm_nb);
}
-static void hyp_cpu_pm_exit(void)
+static void __init hyp_cpu_pm_exit(void)
{
if (!is_protected_kvm_enabled())
cpu_pm_unregister_notifier(_init_cpu_pm_nb);
}
#else
-static inline void hyp_cpu_pm_init(void)
+static inline void __init hyp_cpu_pm_init(void)
{
}
-static inline void
[PATCH v2 21/50] KVM: MIPS: Hardcode callbacks to hardware virtualization extensions
Now that KVM no longer supports trap-and-emulate (see commit 45c7e8af4a5e
"MIPS: Remove KVM_TE support"), hardcode the MIPS callbacks to the
virtualization callbacks.
Harcoding the callbacks eliminates the technically-unnecessary check on
non-NULL kvm_mips_callbacks in kvm_arch_init(). MIPS has never supported
multiple in-tree modules, i.e. barring an out-of-tree module, where
copying and renaming kvm.ko counts as "out-of-tree", KVM could never
encounter a non-NULL set of callbacks during module init.
The callback check is also subtly broken, as it is not thread safe,
i.e. if there were multiple modules, loading both concurrently would
create a race between checking and setting kvm_mips_callbacks.
Given that out-of-tree shenanigans are not the kernel's responsibility,
hardcode the callbacks to simplify the code.
Signed-off-by: Sean Christopherson
---
arch/mips/include/asm/kvm_host.h | 2 +-
arch/mips/kvm/Makefile | 2 +-
arch/mips/kvm/callback.c | 14 --
arch/mips/kvm/mips.c | 9 ++---
arch/mips/kvm/vz.c | 7 ---
5 files changed, 8 insertions(+), 26 deletions(-)
delete mode 100644 arch/mips/kvm/callback.c
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 28f0ba97db71..2803c9c21ef9 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -758,7 +758,7 @@ struct kvm_mips_callbacks {
void (*vcpu_reenter)(struct kvm_vcpu *vcpu);
};
extern struct kvm_mips_callbacks *kvm_mips_callbacks;
-int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks);
+int kvm_mips_emulation_init(void);
/* Debug: dump vcpu state */
int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu);
diff --git a/arch/mips/kvm/Makefile b/arch/mips/kvm/Makefile
index 21ff75bcdbc4..805aeea2166e 100644
--- a/arch/mips/kvm/Makefile
+++ b/arch/mips/kvm/Makefile
@@ -17,4 +17,4 @@ kvm-$(CONFIG_CPU_LOONGSON64) += loongson_ipi.o
kvm-y += vz.o
obj-$(CONFIG_KVM) += kvm.o
-obj-y += callback.o tlb.o
+obj-y += tlb.o
diff --git a/arch/mips/kvm/callback.c b/arch/mips/kvm/callback.c
deleted file mode 100644
index d88aa2173fb0..
--- a/arch/mips/kvm/callback.c
+++ /dev/null
@@ -1,14 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
- * Authors: Yann Le Du
- */
-
-#include
-#include
-
-struct kvm_mips_callbacks *kvm_mips_callbacks;
-EXPORT_SYMBOL_GPL(kvm_mips_callbacks);
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index af29490d9740..f0a6c245d1ff 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -1012,17 +1012,12 @@ long kvm_arch_vm_ioctl(struct file *filp, unsigned int
ioctl, unsigned long arg)
int kvm_arch_init(void *opaque)
{
- if (kvm_mips_callbacks) {
- kvm_err("kvm: module already exists\n");
- return -EEXIST;
- }
-
- return kvm_mips_emulation_init(_mips_callbacks);
+ return kvm_mips_emulation_init();
}
void kvm_arch_exit(void)
{
- kvm_mips_callbacks = NULL;
+
}
int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
diff --git a/arch/mips/kvm/vz.c b/arch/mips/kvm/vz.c
index c706f5890a05..dafab003ea0d 100644
--- a/arch/mips/kvm/vz.c
+++ b/arch/mips/kvm/vz.c
@@ -3304,7 +3304,10 @@ static struct kvm_mips_callbacks kvm_vz_callbacks = {
.vcpu_reenter = kvm_vz_vcpu_reenter,
};
-int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
+/* FIXME: Get rid of the callbacks now that trap-and-emulate is gone. */
+struct kvm_mips_callbacks *kvm_mips_callbacks = _vz_callbacks;
+
+int kvm_mips_emulation_init(void)
{
if (!cpu_has_vz)
return -ENODEV;
@@ -3318,7 +3321,5 @@ int kvm_mips_emulation_init(struct kvm_mips_callbacks
**install_callbacks)
return -ENODEV;
pr_info("Starting KVM with MIPS VZ extensions\n");
-
- *install_callbacks = _vz_callbacks;
return 0;
}
--
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[PATCH v2 22/50] KVM: MIPS: Setup VZ emulation? directly from kvm_mips_init()
Invoke kvm_mips_emulation_init() directly from kvm_mips_init() instead
of bouncing through kvm_init()=>kvm_arch_init(). Functionally, this is
a glorified nop as invoking kvm_arch_init() is the very first action
performed by kvm_init().
Emptying kvm_arch_init() will allow dropping the hook entirely once all
architecture implementations are nops.
No functional change intended.
Signed-off-by: Sean Christopherson
Reviewed-by: Philippe Mathieu-Daudé
---
arch/mips/kvm/mips.c | 6 +-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index f0a6c245d1ff..75681281e2df 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -1012,7 +1012,7 @@ long kvm_arch_vm_ioctl(struct file *filp, unsigned int
ioctl, unsigned long arg)
int kvm_arch_init(void *opaque)
{
- return kvm_mips_emulation_init();
+ return 0;
}
void kvm_arch_exit(void)
@@ -1636,6 +1636,10 @@ static int __init kvm_mips_init(void)
if (ret)
return ret;
+ ret = kvm_mips_emulation_init();
+ if (ret)
+ return ret;
+
ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
if (ret)
--
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[PATCH v2 19/50] KVM: arm64: Do arm/arch initialization without bouncing through kvm_init()
Do arm/arch specific initialization directly in arm's module_init(), now
called kvm_arm_init(), instead of bouncing through kvm_init() to reach
kvm_arch_init(). Invoking kvm_arch_init() is the very first action
performed by kvm_init(), so from a initialization perspective this is a
glorified nop.
Avoiding kvm_arch_init() also fixes a mostly benign bug as kvm_arch_exit()
doesn't properly unwind if a later stage of kvm_init() fails. While the
soon-to-be-deleted comment about compiling as a module being unsupported
is correct, kvm_arch_exit() can still be called by kvm_init() if any step
after the call to kvm_arch_init() succeeds.
Add a FIXME to call out that pKVM initialization isn't unwound if
kvm_init() fails, which is a pre-existing problem inherited from
kvm_arch_exit().
Making kvm_arch_init() a nop will also allow dropping kvm_arch_init() and
kvm_arch_exit() entirely once all other architectures follow suit.
Signed-off-by: Sean Christopherson
---
arch/arm64/kvm/arm.c | 25 -
1 file changed, 16 insertions(+), 9 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index e6f6fcfe6bcc..d3a4db1abf32 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -2195,7 +2195,7 @@ void kvm_arch_irq_bypass_start(struct irq_bypass_consumer
*cons)
/**
* Initialize Hyp-mode and memory mappings on all CPUs.
*/
-int kvm_arch_init(void *opaque)
+int kvm_arm_init(void)
{
int err;
bool in_hyp_mode;
@@ -2269,6 +2269,14 @@ int kvm_arch_init(void *opaque)
kvm_info("Hyp mode initialized successfully\n");
}
+ /*
+* FIXME: Do something reasonable if kvm_init() fails after pKVM
+* hypervisor protection is finalized.
+*/
+ err = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+ if (err)
+ goto out_subs;
+
return 0;
out_subs:
@@ -2281,10 +2289,15 @@ int kvm_arch_init(void *opaque)
return err;
}
+int kvm_arch_init(void *opaque)
+{
+ return 0;
+}
+
/* NOP: Compiling as a module not supported */
void kvm_arch_exit(void)
{
- kvm_unregister_perf_callbacks();
+
}
static int __init early_kvm_mode_cfg(char *arg)
@@ -2325,10 +2338,4 @@ enum kvm_mode kvm_get_mode(void)
return kvm_mode;
}
-static int arm_init(void)
-{
- int rc = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
- return rc;
-}
-
-module_init(arm_init);
+module_init(kvm_arm_init);
--
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[PATCH v2 16/50] KVM: arm64: Simplify the CPUHP logic
From: Marc Zyngier
For a number of historical reasons, the KVM/arm64 hotplug setup is pretty
complicated, and we have two extra CPUHP notifiers for vGIC and timers.
It looks pretty pointless, and gets in the way of further changes.
So let's just expose some helpers that can be called from the core
CPUHP callback, and get rid of everything else.
This gives us the opportunity to drop a useless notifier entry,
as well as tidy-up the timer enable/disable, which was a bit odd.
Signed-off-by: Marc Zyngier
Signed-off-by: Isaku Yamahata
Signed-off-by: Sean Christopherson
---
arch/arm64/kvm/arch_timer.c | 27 ++-
arch/arm64/kvm/arm.c| 13 +
arch/arm64/kvm/vgic/vgic-init.c | 19 ++-
include/kvm/arm_arch_timer.h| 4
include/kvm/arm_vgic.h | 4
include/linux/cpuhotplug.h | 3 ---
6 files changed, 33 insertions(+), 37 deletions(-)
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index bb24a76b4224..33fca1a691a5 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -811,10 +811,18 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
ptimer->host_timer_irq_flags = host_ptimer_irq_flags;
}
-static void kvm_timer_init_interrupt(void *info)
+void kvm_timer_cpu_up(void)
{
enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
- enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags);
+ if (host_ptimer_irq)
+ enable_percpu_irq(host_ptimer_irq, host_ptimer_irq_flags);
+}
+
+void kvm_timer_cpu_down(void)
+{
+ disable_percpu_irq(host_vtimer_irq);
+ if (host_ptimer_irq)
+ disable_percpu_irq(host_ptimer_irq);
}
int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
@@ -976,18 +984,6 @@ void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu,
preempt_enable();
}
-static int kvm_timer_starting_cpu(unsigned int cpu)
-{
- kvm_timer_init_interrupt(NULL);
- return 0;
-}
-
-static int kvm_timer_dying_cpu(unsigned int cpu)
-{
- disable_percpu_irq(host_vtimer_irq);
- return 0;
-}
-
static int timer_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
{
if (vcpu)
@@ -1185,9 +1181,6 @@ int kvm_timer_hyp_init(bool has_gic)
goto out_free_irq;
}
- cpuhp_setup_state(CPUHP_AP_KVM_ARM_TIMER_STARTING,
- "kvm/arm/timer:starting", kvm_timer_starting_cpu,
- kvm_timer_dying_cpu);
return 0;
out_free_irq:
free_percpu_irq(host_vtimer_irq, kvm_get_running_vcpus());
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index c6732ac329ca..07f5cef5c33b 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1670,7 +1670,15 @@ static void _kvm_arch_hardware_enable(void *discard)
int kvm_arch_hardware_enable(void)
{
+ int was_enabled = __this_cpu_read(kvm_arm_hardware_enabled);
+
_kvm_arch_hardware_enable(NULL);
+
+ if (!was_enabled) {
+ kvm_vgic_cpu_up();
+ kvm_timer_cpu_up();
+ }
+
return 0;
}
@@ -1684,6 +1692,11 @@ static void _kvm_arch_hardware_disable(void *discard)
void kvm_arch_hardware_disable(void)
{
+ if (__this_cpu_read(kvm_arm_hardware_enabled)) {
+ kvm_timer_cpu_down();
+ kvm_vgic_cpu_down();
+ }
+
if (!is_protected_kvm_enabled())
_kvm_arch_hardware_disable(NULL);
}
diff --git a/arch/arm64/kvm/vgic/vgic-init.c b/arch/arm64/kvm/vgic/vgic-init.c
index f6d4f4052555..6c7f6ae21ec0 100644
--- a/arch/arm64/kvm/vgic/vgic-init.c
+++ b/arch/arm64/kvm/vgic/vgic-init.c
@@ -465,17 +465,15 @@ int kvm_vgic_map_resources(struct kvm *kvm)
/* GENERIC PROBE */
-static int vgic_init_cpu_starting(unsigned int cpu)
+void kvm_vgic_cpu_up(void)
{
enable_percpu_irq(kvm_vgic_global_state.maint_irq, 0);
- return 0;
}
-static int vgic_init_cpu_dying(unsigned int cpu)
+void kvm_vgic_cpu_down(void)
{
disable_percpu_irq(kvm_vgic_global_state.maint_irq);
- return 0;
}
static irqreturn_t vgic_maintenance_handler(int irq, void *data)
@@ -584,19 +582,6 @@ int kvm_vgic_hyp_init(void)
return ret;
}
- ret = cpuhp_setup_state(CPUHP_AP_KVM_ARM_VGIC_INIT_STARTING,
- "kvm/arm/vgic:starting",
- vgic_init_cpu_starting, vgic_init_cpu_dying);
- if (ret) {
- kvm_err("Cannot register vgic CPU notifier\n");
- goto out_free_irq;
- }
-
kvm_info("vgic interrupt IRQ%d\n", kvm_vgic_global_state.maint_irq);
return 0;
-
-out_free_irq:
- free_percpu_irq(kvm_vgic_global_state.maint_irq,
- kvm_get_running_vcpus());
- return ret;
}
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index cd6d8f260eab..1638418f72dd 100644
---
[PATCH v2 15/50] KVM: x86: Serialize vendor module initialization (hardware setup)
Acquire a new mutex, vendor_module_lock, in kvm_x86_vendor_init() while
doing hardware setup to ensure that concurrent calls are fully serialized.
KVM rejects attempts to load vendor modules if a different module has
already been loaded, but doesn't handle the case where multiple vendor
modules are loaded at the same time, and module_init() doesn't run under
the global module_mutex.
Note, in practice, this is likely a benign bug as no platform exists that
supports both SVM and VMX, i.e. barring a weird VM setup, one of the
vendor modules is guaranteed to fail a support check before modifying
common KVM state.
Alternatively, KVM could perform an atomic CMPXCHG on .hardware_enable,
but that comes with its own ugliness as it would require setting
.hardware_enable before success is guaranteed, e.g. attempting to load
the "wrong" could result in spurious failure to load the "right" module.
Introduce a new mutex as using kvm_lock is extremely deadlock prone due
to kvm_lock being taken under cpus_write_lock(), and in the future, under
under cpus_read_lock(). Any operation that takes cpus_read_lock() while
holding kvm_lock would potentially deadlock, e.g. kvm_timer_init() takes
cpus_read_lock() to register a callback. In theory, KVM could avoid
such problematic paths, i.e. do less setup under kvm_lock, but avoiding
all calls to cpus_read_lock() is subtly difficult and thus fragile. E.g.
updating static calls also acquires cpus_read_lock().
Inverting the lock ordering, i.e. always taking kvm_lock outside
cpus_read_lock(), is not a viable option as kvm_lock is taken in various
callbacks that may be invoked under cpus_read_lock(), e.g. x86's
kvmclock_cpufreq_notifier().
The lockdep splat below is dependent on future patches to take
cpus_read_lock() in hardware_enable_all(), but as above, deadlock is
already is already possible.
==
WARNING: possible circular locking dependency detected
6.0.0-smp--7ec93244f194-init2 #27 Tainted: G O
--
stable/251833 is trying to acquire lock:
c097ea28 (kvm_lock){+.+.}-{3:3}, at: hardware_enable_all+0x1f/0xc0
[kvm]
but task is already holding lock:
a2456828 (cpu_hotplug_lock){}-{0:0}, at:
hardware_enable_all+0xf/0xc0 [kvm]
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (cpu_hotplug_lock){}-{0:0}:
cpus_read_lock+0x2a/0xa0
__cpuhp_setup_state+0x2b/0x60
__kvm_x86_vendor_init+0x16a/0x1870 [kvm]
kvm_x86_vendor_init+0x23/0x40 [kvm]
0xc0a4d02b
do_one_initcall+0x110/0x200
do_init_module+0x4f/0x250
load_module+0x1730/0x18f0
__se_sys_finit_module+0xca/0x100
__x64_sys_finit_module+0x1d/0x20
do_syscall_64+0x3d/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
-> #0 (kvm_lock){+.+.}-{3:3}:
__lock_acquire+0x16f4/0x30d0
lock_acquire+0xb2/0x190
__mutex_lock+0x98/0x6f0
mutex_lock_nested+0x1b/0x20
hardware_enable_all+0x1f/0xc0 [kvm]
kvm_dev_ioctl+0x45e/0x930 [kvm]
__se_sys_ioctl+0x77/0xc0
__x64_sys_ioctl+0x1d/0x20
do_syscall_64+0x3d/0x80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0CPU1
lock(cpu_hotplug_lock);
lock(kvm_lock);
lock(cpu_hotplug_lock);
lock(kvm_lock);
*** DEADLOCK ***
1 lock held by stable/251833:
#0: a2456828 (cpu_hotplug_lock){}-{0:0}, at:
hardware_enable_all+0xf/0xc0 [kvm]
Signed-off-by: Sean Christopherson
---
Documentation/virt/kvm/locking.rst | 6 ++
arch/x86/kvm/x86.c | 18 --
2 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/Documentation/virt/kvm/locking.rst
b/Documentation/virt/kvm/locking.rst
index 845a561629f1..132a9e5436e5 100644
--- a/Documentation/virt/kvm/locking.rst
+++ b/Documentation/virt/kvm/locking.rst
@@ -282,3 +282,9 @@ time it will be set using the Dirty tracking mechanism
described above.
wakeup notification event since external interrupts from the
assigned devices happens, we will find the vCPU on the list to
wakeup.
+
+``vendor_module_lock``
+
+:Type: mutex
+:Arch: x86
+:Protects: loading a vendor module (kvm_amd or kvm_intel)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b33932fca36e..45184ca89317 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -128,6 +128,7 @@ static int kvm_vcpu_do_singlestep(struct kvm_vcpu *vcpu);
static
[PATCH v2 18/50] KVM: arm64: Unregister perf callbacks if hypervisor finalization fails
Undo everything done by init_subsystems() if a later initialization step
fails, i.e. unregister perf callbacks in addition to unregistering the
power management notifier.
Fixes: bfa79a805454 ("KVM: arm64: Elevate hypervisor mappings creation at EL2")
Signed-off-by: Sean Christopherson
---
arch/arm64/kvm/arm.c | 13 +++--
1 file changed, 11 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index fa986ebb4793..e6f6fcfe6bcc 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -1839,12 +1839,21 @@ static int init_subsystems(void)
kvm_register_perf_callbacks(NULL);
out:
+ if (err)
+ hyp_cpu_pm_exit();
+
if (err || !is_protected_kvm_enabled())
on_each_cpu(_kvm_arch_hardware_disable, NULL, 1);
return err;
}
+static void teardown_subsystems(void)
+{
+ kvm_unregister_perf_callbacks();
+ hyp_cpu_pm_exit();
+}
+
static void teardown_hyp_mode(void)
{
int cpu;
@@ -2242,7 +2251,7 @@ int kvm_arch_init(void *opaque)
err = init_subsystems();
if (err)
- goto out_subs;
+ goto out_hyp;
if (!in_hyp_mode) {
err = finalize_hyp_mode();
@@ -2263,7 +2272,7 @@ int kvm_arch_init(void *opaque)
return 0;
out_subs:
- hyp_cpu_pm_exit();
+ teardown_subsystems();
out_hyp:
if (!in_hyp_mode)
teardown_hyp_mode();
--
2.38.1.584.g0f3c55d4c2-goog
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[PATCH v2 17/50] KVM: arm64: Free hypervisor allocations if vector slot init fails
Teardown hypervisor mode if vector slot setup fails in order to avoid
leaking any allocations done by init_hyp_mode().
Fixes: b881cdce77b4 ("KVM: arm64: Allocate hyp vectors statically")
Signed-off-by: Sean Christopherson
---
arch/arm64/kvm/arm.c | 15 ---
1 file changed, 8 insertions(+), 7 deletions(-)
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 07f5cef5c33b..fa986ebb4793 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -2237,18 +2237,18 @@ int kvm_arch_init(void *opaque)
err = kvm_init_vector_slots();
if (err) {
kvm_err("Cannot initialise vector slots\n");
- goto out_err;
- }
-
- err = init_subsystems();
- if (err)
goto out_hyp;
+ }
+
+ err = init_subsystems();
+ if (err)
+ goto out_subs;
if (!in_hyp_mode) {
err = finalize_hyp_mode();
if (err) {
kvm_err("Failed to finalize Hyp protection\n");
- goto out_hyp;
+ goto out_subs;
}
}
@@ -2262,8 +2262,9 @@ int kvm_arch_init(void *opaque)
return 0;
-out_hyp:
+out_subs:
hyp_cpu_pm_exit();
+out_hyp:
if (!in_hyp_mode)
teardown_hyp_mode();
out_err:
--
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[PATCH v2 14/50] KVM: VMX: Do _all_ initialization before exposing /dev/kvm to userspace
Call kvm_init() only after _all_ setup is complete, as kvm_init() exposes
/dev/kvm to userspace and thus allows userspace to create VMs (and call
other ioctls). E.g. KVM will encounter a NULL pointer when attempting to
add a vCPU to the per-CPU loaded_vmcss_on_cpu list if userspace is able to
create a VM before vmx_init() configures said list.
BUG: kernel NULL pointer dereference, address: 0008
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] SMP
CPU: 6 PID: 1143 Comm: stable Not tainted 6.0.0-rc7+ #988
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
RIP: 0010:vmx_vcpu_load_vmcs+0x68/0x230 [kvm_intel]
vmx_vcpu_load+0x16/0x60 [kvm_intel]
kvm_arch_vcpu_load+0x32/0x1f0 [kvm]
vcpu_load+0x2f/0x40 [kvm]
kvm_arch_vcpu_create+0x231/0x310 [kvm]
kvm_vm_ioctl+0x79f/0xe10 [kvm]
? handle_mm_fault+0xb1/0x220
__x64_sys_ioctl+0x80/0xb0
do_syscall_64+0x2b/0x50
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f5a6b05743b
Modules linked in: vhost_net vhost vhost_iotlb tap kvm_intel(+) kvm irqbypass
Cc: sta...@vger.kernel.org
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/vmx/vmx.c | 34 +-
1 file changed, 21 insertions(+), 13 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 8e81cd94407d..76185a7a7ded 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8521,19 +8521,23 @@ static void vmx_cleanup_l1d_flush(void)
l1tf_vmx_mitigation = VMENTER_L1D_FLUSH_AUTO;
}
-static void vmx_exit(void)
+static void __vmx_exit(void)
{
+ allow_smaller_maxphyaddr = false;
+
#ifdef CONFIG_KEXEC_CORE
RCU_INIT_POINTER(crash_vmclear_loaded_vmcss, NULL);
synchronize_rcu();
#endif
-
- kvm_exit();
- kvm_x86_vendor_exit();
-
vmx_cleanup_l1d_flush();
+}
- allow_smaller_maxphyaddr = false;
+static void vmx_exit(void)
+{
+ kvm_exit();
+ kvm_x86_vendor_exit();
+
+ __vmx_exit();
}
module_exit(vmx_exit);
@@ -8551,11 +8555,6 @@ static int __init vmx_init(void)
if (r)
return r;
- r = kvm_init(_init_ops, sizeof(struct vcpu_vmx),
-__alignof__(struct vcpu_vmx), THIS_MODULE);
- if (r)
- goto err_kvm_init;
-
/*
* Must be called after common x86 init so enable_ept is properly set
* up. Hand the parameter mitigation value in which was stored in
@@ -8589,11 +8588,20 @@ static int __init vmx_init(void)
if (!enable_ept)
allow_smaller_maxphyaddr = true;
+ /*
+* Common KVM initialization _must_ come last, after this, /dev/kvm is
+* exposed to userspace!
+*/
+ r = kvm_init(_init_ops, sizeof(struct vcpu_vmx),
+__alignof__(struct vcpu_vmx), THIS_MODULE);
+ if (r)
+ goto err_kvm_init;
+
return 0;
-err_l1d_flush:
- vmx_exit();
err_kvm_init:
+ __vmx_exit();
+err_l1d_flush:
kvm_x86_vendor_exit();
return r;
}
--
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[PATCH v2 12/50] KVM: VMX: Move Hyper-V eVMCS initialization to helper
Move Hyper-V's eVMCS initialization to a dedicated helper to clean up
vmx_init(), and add a comment to call out that the Hyper-V init code
doesn't need to be unwound if vmx_init() ultimately fails.
No functional change intended.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/vmx/vmx.c | 73 +-
1 file changed, 43 insertions(+), 30 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index c0de7160700b..b8bf95b9710d 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -523,6 +523,8 @@ static inline void vmx_segment_cache_clear(struct vcpu_vmx
*vmx)
static unsigned long host_idt_base;
#if IS_ENABLED(CONFIG_HYPERV)
+static struct kvm_x86_ops vmx_x86_ops __initdata;
+
static bool __read_mostly enlightened_vmcs = true;
module_param(enlightened_vmcs, bool, 0444);
@@ -551,6 +553,43 @@ static int hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)
return 0;
}
+static __init void hv_init_evmcs(void)
+{
+ int cpu;
+
+ if (!enlightened_vmcs)
+ return;
+
+ /*
+* Enlightened VMCS usage should be recommended and the host needs
+* to support eVMCS v1 or above.
+*/
+ if (ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED &&
+ (ms_hyperv.nested_features & HV_X64_ENLIGHTENED_VMCS_VERSION) >=
+KVM_EVMCS_VERSION) {
+
+ /* Check that we have assist pages on all online CPUs */
+ for_each_online_cpu(cpu) {
+ if (!hv_get_vp_assist_page(cpu)) {
+ enlightened_vmcs = false;
+ break;
+ }
+ }
+
+ if (enlightened_vmcs) {
+ pr_info("KVM: vmx: using Hyper-V Enlightened VMCS\n");
+ static_branch_enable(_evmcs);
+ }
+
+ if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
+ vmx_x86_ops.enable_l2_tlb_flush
+ = hv_enable_l2_tlb_flush;
+
+ } else {
+ enlightened_vmcs = false;
+ }
+}
+
static void hv_reset_evmcs(void)
{
struct hv_vp_assist_page *vp_ap;
@@ -577,6 +616,7 @@ static void hv_reset_evmcs(void)
}
#else /* IS_ENABLED(CONFIG_HYPERV) */
+static void hv_init_evmcs(void) {}
static void hv_reset_evmcs(void) {}
#endif /* IS_ENABLED(CONFIG_HYPERV) */
@@ -8500,38 +8540,11 @@ static int __init vmx_init(void)
{
int r, cpu;
-#if IS_ENABLED(CONFIG_HYPERV)
/*
-* Enlightened VMCS usage should be recommended and the host needs
-* to support eVMCS v1 or above. We can also disable eVMCS support
-* with module parameter.
+* Note, hv_init_evmcs() touches only VMX knobs, i.e. there's nothing
+* to unwind if a later step fails.
*/
- if (enlightened_vmcs &&
- ms_hyperv.hints & HV_X64_ENLIGHTENED_VMCS_RECOMMENDED &&
- (ms_hyperv.nested_features & HV_X64_ENLIGHTENED_VMCS_VERSION) >=
- KVM_EVMCS_VERSION) {
-
- /* Check that we have assist pages on all online CPUs */
- for_each_online_cpu(cpu) {
- if (!hv_get_vp_assist_page(cpu)) {
- enlightened_vmcs = false;
- break;
- }
- }
-
- if (enlightened_vmcs) {
- pr_info("KVM: vmx: using Hyper-V Enlightened VMCS\n");
- static_branch_enable(_evmcs);
- }
-
- if (ms_hyperv.nested_features & HV_X64_NESTED_DIRECT_FLUSH)
- vmx_x86_ops.enable_l2_tlb_flush
- = hv_enable_l2_tlb_flush;
-
- } else {
- enlightened_vmcs = false;
- }
-#endif
+ hv_init_evmcs();
r = kvm_init(_init_ops, sizeof(struct vcpu_vmx),
__alignof__(struct vcpu_vmx), THIS_MODULE);
--
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[PATCH v2 11/50] KVM: VMX: Don't bother disabling eVMCS static key on module exit
Don't disable the eVMCS static key on module exit, kvm_intel.ko owns the key so there can't possibly be users after the kvm_intel.ko is unloaded, at least not without much bigger issues. Signed-off-by: Sean Christopherson --- arch/x86/kvm/vmx/vmx.c | 4 1 file changed, 4 deletions(-) diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index d85d175dca70..c0de7160700b 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -8490,10 +8490,6 @@ static void vmx_exit(void) kvm_exit(); -#if IS_ENABLED(CONFIG_HYPERV) - if (static_branch_unlikely(_evmcs)) - static_branch_disable(_evmcs); -#endif vmx_cleanup_l1d_flush(); allow_smaller_maxphyaddr = false; -- 2.38.1.584.g0f3c55d4c2-goog ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
[PATCH v2 13/50] KVM: x86: Move guts of kvm_arch_init() to standalone helper
Move the guts of kvm_arch_init() to a new helper, kvm_x86_vendor_init(),
so that VMX can do _all_ arch and vendor initialization before calling
kvm_init(). Calling kvm_init() must be the _very_ last step during init,
as kvm_init() exposes /dev/kvm to userspace, i.e. allows creating VMs.
No functional change intended.
Signed-off-by: Sean Christopherson
---
arch/x86/include/asm/kvm_host.h | 3 +++
arch/x86/kvm/svm/svm.c | 23 +--
arch/x86/kvm/vmx/vmx.c | 21 +++--
arch/x86/kvm/x86.c | 15 +--
4 files changed, 52 insertions(+), 10 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 70af7240a1d5..04a9ae66fb8d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1758,6 +1758,9 @@ extern struct kvm_x86_ops kvm_x86_ops;
#define KVM_X86_OP_OPTIONAL_RET0 KVM_X86_OP
#include
+int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops);
+void kvm_x86_vendor_exit(void);
+
#define __KVM_HAVE_ARCH_VM_ALLOC
static inline struct kvm *kvm_arch_alloc_vm(void)
{
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 91352d692845..19e81a99c58f 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -5091,15 +5091,34 @@ static struct kvm_x86_init_ops svm_init_ops __initdata
= {
static int __init svm_init(void)
{
+ int r;
+
__unused_size_checks();
- return kvm_init(_init_ops, sizeof(struct vcpu_svm),
- __alignof__(struct vcpu_svm), THIS_MODULE);
+ r = kvm_x86_vendor_init(_init_ops);
+ if (r)
+ return r;
+
+ /*
+* Common KVM initialization _must_ come last, after this, /dev/kvm is
+* exposed to userspace!
+*/
+ r = kvm_init(_init_ops, sizeof(struct vcpu_svm),
+__alignof__(struct vcpu_svm), THIS_MODULE);
+ if (r)
+ goto err_kvm_init;
+
+ return 0;
+
+err_kvm_init:
+ kvm_x86_vendor_exit();
+ return r;
}
static void __exit svm_exit(void)
{
kvm_exit();
+ kvm_x86_vendor_exit();
}
module_init(svm_init)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b8bf95b9710d..8e81cd94407d 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -8529,6 +8529,7 @@ static void vmx_exit(void)
#endif
kvm_exit();
+ kvm_x86_vendor_exit();
vmx_cleanup_l1d_flush();
@@ -8546,23 +8547,25 @@ static int __init vmx_init(void)
*/
hv_init_evmcs();
+ r = kvm_x86_vendor_init(_init_ops);
+ if (r)
+ return r;
+
r = kvm_init(_init_ops, sizeof(struct vcpu_vmx),
__alignof__(struct vcpu_vmx), THIS_MODULE);
if (r)
- return r;
+ goto err_kvm_init;
/*
-* Must be called after kvm_init() so enable_ept is properly set
+* Must be called after common x86 init so enable_ept is properly set
* up. Hand the parameter mitigation value in which was stored in
* the pre module init parser. If no parameter was given, it will
* contain 'auto' which will be turned into the default 'cond'
* mitigation mode.
*/
r = vmx_setup_l1d_flush(vmentry_l1d_flush_param);
- if (r) {
- vmx_exit();
- return r;
- }
+ if (r)
+ goto err_l1d_flush;
vmx_setup_fb_clear_ctrl();
@@ -8587,5 +8590,11 @@ static int __init vmx_init(void)
allow_smaller_maxphyaddr = true;
return 0;
+
+err_l1d_flush:
+ vmx_exit();
+err_kvm_init:
+ kvm_x86_vendor_exit();
+ return r;
}
module_init(vmx_init);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 915d57c3b41d..b33932fca36e 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9278,7 +9278,16 @@ static inline void kvm_ops_update(struct
kvm_x86_init_ops *ops)
int kvm_arch_init(void *opaque)
{
- struct kvm_x86_init_ops *ops = opaque;
+ return 0;
+}
+
+void kvm_arch_exit(void)
+{
+
+}
+
+int kvm_x86_vendor_init(struct kvm_x86_init_ops *ops)
+{
u64 host_pat;
int r;
@@ -9410,8 +9419,9 @@ int kvm_arch_init(void *opaque)
kmem_cache_destroy(x86_emulator_cache);
return r;
}
+EXPORT_SYMBOL_GPL(kvm_x86_vendor_init);
-void kvm_arch_exit(void)
+void kvm_x86_vendor_exit(void)
{
kvm_unregister_perf_callbacks();
@@ -9440,6 +9450,7 @@ void kvm_arch_exit(void)
WARN_ON(static_branch_unlikely(_xen_enabled.key));
#endif
}
+EXPORT_SYMBOL_GPL(kvm_x86_vendor_exit);
static int __kvm_emulate_halt(struct kvm_vcpu *vcpu, int state, int reason)
{
--
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[PATCH v2 10/50] KVM: VMX: Reset eVMCS controls in VP assist page during hardware disabling
Reset the eVMCS controls in the per-CPU VP assist page during hardware
disabling instead of waiting until kvm-intel's module exit. The controls
are activated if and only if KVM creates a VM, i.e. don't need to be
reset if hardware is never enabled.
Doing the reset during hardware disabling will naturally fix a potential
NULL pointer deref bug once KVM disables CPU hotplug while enabling and
disabling hardware (which is necessary to fix a variety of bugs). If the
kernel is running as the root partition, the VP assist page is unmapped
during CPU hot unplug, and so KVM's clearing of the eVMCS controls needs
to occur with CPU hot(un)plug disabled, otherwise KVM could attempt to
write to a CPU's VP assist page after it's unmapped.
Reported-by: Vitaly Kuznetsov
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/vmx/vmx.c | 50 +-
1 file changed, 30 insertions(+), 20 deletions(-)
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index cea8c07f5229..d85d175dca70 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -551,6 +551,33 @@ static int hv_enable_l2_tlb_flush(struct kvm_vcpu *vcpu)
return 0;
}
+static void hv_reset_evmcs(void)
+{
+ struct hv_vp_assist_page *vp_ap;
+
+ if (!static_branch_unlikely(_evmcs))
+ return;
+
+ /*
+* KVM should enable eVMCS if and only if all CPUs have a VP assist
+* page, and should reject CPU onlining if eVMCS is enabled the CPU
+* doesn't have a VP assist page allocated.
+*/
+ vp_ap = hv_get_vp_assist_page(smp_processor_id());
+ if (WARN_ON_ONCE(!vp_ap))
+ return;
+
+ /*
+* Reset everything to support using non-enlightened VMCS access later
+* (e.g. when we reload the module with enlightened_vmcs=0)
+*/
+ vp_ap->nested_control.features.directhypercall = 0;
+ vp_ap->current_nested_vmcs = 0;
+ vp_ap->enlighten_vmentry = 0;
+}
+
+#else /* IS_ENABLED(CONFIG_HYPERV) */
+static void hv_reset_evmcs(void) {}
#endif /* IS_ENABLED(CONFIG_HYPERV) */
/*
@@ -2496,6 +2523,8 @@ static void vmx_hardware_disable(void)
if (cpu_vmxoff())
kvm_spurious_fault();
+ hv_reset_evmcs();
+
intel_pt_handle_vmx(0);
}
@@ -8462,27 +8491,8 @@ static void vmx_exit(void)
kvm_exit();
#if IS_ENABLED(CONFIG_HYPERV)
- if (static_branch_unlikely(_evmcs)) {
- int cpu;
- struct hv_vp_assist_page *vp_ap;
- /*
-* Reset everything to support using non-enlightened VMCS
-* access later (e.g. when we reload the module with
-* enlightened_vmcs=0)
-*/
- for_each_online_cpu(cpu) {
- vp_ap = hv_get_vp_assist_page(cpu);
-
- if (!vp_ap)
- continue;
-
- vp_ap->nested_control.features.directhypercall = 0;
- vp_ap->current_nested_vmcs = 0;
- vp_ap->enlighten_vmentry = 0;
- }
-
+ if (static_branch_unlikely(_evmcs))
static_branch_disable(_evmcs);
- }
#endif
vmx_cleanup_l1d_flush();
--
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[PATCH v2 09/50] KVM: Drop arch hardware (un)setup hooks
Drop kvm_arch_hardware_setup() and kvm_arch_hardware_unsetup() now that
all implementations are nops.
No functional change intended.
Signed-off-by: Sean Christopherson
Reviewed-by: Eric Farman # s390
Acked-by: Anup Patel
---
arch/arm64/include/asm/kvm_host.h | 1 -
arch/arm64/kvm/arm.c| 5 -
arch/mips/include/asm/kvm_host.h| 1 -
arch/mips/kvm/mips.c| 5 -
arch/powerpc/include/asm/kvm_host.h | 1 -
arch/powerpc/kvm/powerpc.c | 5 -
arch/riscv/include/asm/kvm_host.h | 1 -
arch/riscv/kvm/main.c | 5 -
arch/s390/kvm/kvm-s390.c| 10 --
arch/x86/kvm/x86.c | 10 --
include/linux/kvm_host.h| 2 --
virt/kvm/kvm_main.c | 7 ---
12 files changed, 53 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h
b/arch/arm64/include/asm/kvm_host.h
index 45e2136322ba..5d5a887e63a5 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -859,7 +859,6 @@ static inline bool kvm_system_needs_idmapped_vectors(void)
void kvm_arm_vcpu_ptrauth_trap(struct kvm_vcpu *vcpu);
-static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
index 7b107fa540fa..c6732ac329ca 100644
--- a/arch/arm64/kvm/arm.c
+++ b/arch/arm64/kvm/arm.c
@@ -63,11 +63,6 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
return kvm_vcpu_exiting_guest_mode(vcpu) == IN_GUEST_MODE;
}
-int kvm_arch_hardware_setup(void *opaque)
-{
- return 0;
-}
-
int kvm_arch_check_processor_compat(void *opaque)
{
return 0;
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 5cedb28e8a40..28f0ba97db71 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -888,7 +888,6 @@ extern unsigned long kvm_mips_get_ramsize(struct kvm *kvm);
extern int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
struct kvm_mips_interrupt *irq);
-static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_free_memslot(struct kvm *kvm,
struct kvm_memory_slot *slot) {}
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index a25e0b73ee70..af29490d9740 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -135,11 +135,6 @@ void kvm_arch_hardware_disable(void)
kvm_mips_callbacks->hardware_disable();
}
-int kvm_arch_hardware_setup(void *opaque)
-{
- return 0;
-}
-
int kvm_arch_check_processor_compat(void *opaque)
{
return 0;
diff --git a/arch/powerpc/include/asm/kvm_host.h
b/arch/powerpc/include/asm/kvm_host.h
index caea15dcb91d..5d2c3a487e73 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -877,7 +877,6 @@ struct kvm_vcpu_arch {
#define __KVM_HAVE_CREATE_DEVICE
static inline void kvm_arch_hardware_disable(void) {}
-static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_memslots_updated(struct kvm *kvm, u64 gen) {}
static inline void kvm_arch_flush_shadow_all(struct kvm *kvm) {}
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 04494a4fb37a..5faf69421f13 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -440,11 +440,6 @@ int kvm_arch_hardware_enable(void)
return 0;
}
-int kvm_arch_hardware_setup(void *opaque)
-{
- return 0;
-}
-
int kvm_arch_check_processor_compat(void *opaque)
{
return kvmppc_core_check_processor_compat();
diff --git a/arch/riscv/include/asm/kvm_host.h
b/arch/riscv/include/asm/kvm_host.h
index dbbf43d52623..8c771fc4f5d2 100644
--- a/arch/riscv/include/asm/kvm_host.h
+++ b/arch/riscv/include/asm/kvm_host.h
@@ -229,7 +229,6 @@ struct kvm_vcpu_arch {
bool pause;
};
-static inline void kvm_arch_hardware_unsetup(void) {}
static inline void kvm_arch_sync_events(struct kvm *kvm) {}
static inline void kvm_arch_sched_in(struct kvm_vcpu *vcpu, int cpu) {}
diff --git a/arch/riscv/kvm/main.c b/arch/riscv/kvm/main.c
index df2d8716851f..a146fa0ce4d2 100644
--- a/arch/riscv/kvm/main.c
+++ b/arch/riscv/kvm/main.c
@@ -25,11 +25,6 @@ int kvm_arch_check_processor_compat(void *opaque)
return 0;
}
-int kvm_arch_hardware_setup(void *opaque)
-{
- return 0;
-}
-
int kvm_arch_hardware_enable(void)
{
unsigned long hideleg, hedeleg;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 97c7ccd189eb..829e6e046003 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -329,16 +329,6 @@ static struct notifier_block kvm_clock_notifier = {
[PATCH v2 07/50] KVM: x86: Do timer initialization after XCR0 configuration
Move kvm_arch_init()'s call to kvm_timer_init() down a few lines below
the XCR0 configuration code. A future patch will move hardware setup
into kvm_arch_init() and slot in vendor hardware setup before the call
to kvm_timer_init() so that timer initialization (among other stuff)
doesn't need to be unwound if vendor setup fails. XCR0 setup on the
other hand needs to happen before vendor hardware setup.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/x86.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f18f579ebde8..a873618564cd 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9326,13 +9326,13 @@ int kvm_arch_init(void *opaque)
if (r)
goto out_free_percpu;
- kvm_timer_init();
-
if (boot_cpu_has(X86_FEATURE_XSAVE)) {
host_xcr0 = xgetbv(XCR_XFEATURE_ENABLED_MASK);
kvm_caps.supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0;
}
+ kvm_timer_init();
+
if (pi_inject_timer == -1)
pi_inject_timer = housekeeping_enabled(HK_TYPE_TIMER);
#ifdef CONFIG_X86_64
--
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[PATCH v2 08/50] KVM: x86: Move hardware setup/unsetup to init/exit
Now that kvm_arch_hardware_setup() is called immediately after
kvm_arch_init(), fold the guts of kvm_arch_hardware_(un)setup() into
kvm_arch_{init,exit}() as a step towards dropping one of the hooks.
To avoid having to unwind various setup, e.g registration of several
notifiers, slot in the vendor hardware setup before the registration of
said notifiers and callbacks. Introducing a functional change while
moving code is less than ideal, but the alternative is adding a pile of
unwinding code, which is much more error prone, e.g. several attempts to
move the setup code verbatim all introduced bugs.
Add a comment to document that kvm_ops_update() is effectively the point
of no return, e.g. it sets the kvm_x86_ops.hardware_enable canary and so
needs to be unwound.
Signed-off-by: Sean Christopherson
---
arch/x86/kvm/x86.c | 121 +++--
1 file changed, 63 insertions(+), 58 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a873618564cd..fe5f2e49b5eb 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9258,6 +9258,24 @@ static struct notifier_block pvclock_gtod_notifier = {
};
#endif
+static inline void kvm_ops_update(struct kvm_x86_init_ops *ops)
+{
+ memcpy(_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops));
+
+#define __KVM_X86_OP(func) \
+ static_call_update(kvm_x86_##func, kvm_x86_ops.func);
+#define KVM_X86_OP(func) \
+ WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func)
+#define KVM_X86_OP_OPTIONAL __KVM_X86_OP
+#define KVM_X86_OP_OPTIONAL_RET0(func) \
+ static_call_update(kvm_x86_##func, (void *)kvm_x86_ops.func ? : \
+ (void *)__static_call_return0);
+#include
+#undef __KVM_X86_OP
+
+ kvm_pmu_ops_update(ops->pmu_ops);
+}
+
int kvm_arch_init(void *opaque)
{
struct kvm_x86_init_ops *ops = opaque;
@@ -9331,6 +9349,24 @@ int kvm_arch_init(void *opaque)
kvm_caps.supported_xcr0 = host_xcr0 & KVM_SUPPORTED_XCR0;
}
+ rdmsrl_safe(MSR_EFER, _efer);
+
+ if (boot_cpu_has(X86_FEATURE_XSAVES))
+ rdmsrl(MSR_IA32_XSS, host_xss);
+
+ kvm_init_pmu_capability();
+
+ r = ops->hardware_setup();
+ if (r != 0)
+ goto out_mmu_exit;
+
+ /*
+* Point of no return! DO NOT add error paths below this point unless
+* absolutely necessary, as most operations from this point forward
+* require unwinding.
+*/
+ kvm_ops_update(ops);
+
kvm_timer_init();
if (pi_inject_timer == -1)
@@ -9342,8 +9378,32 @@ int kvm_arch_init(void *opaque)
set_hv_tscchange_cb(kvm_hyperv_tsc_notifier);
#endif
+ kvm_register_perf_callbacks(ops->handle_intel_pt_intr);
+
+ if (!kvm_cpu_cap_has(X86_FEATURE_XSAVES))
+ kvm_caps.supported_xss = 0;
+
+#define __kvm_cpu_cap_has(UNUSED_, f) kvm_cpu_cap_has(f)
+ cr4_reserved_bits = __cr4_reserved_bits(__kvm_cpu_cap_has, UNUSED_);
+#undef __kvm_cpu_cap_has
+
+ if (kvm_caps.has_tsc_control) {
+ /*
+* Make sure the user can only configure tsc_khz values that
+* fit into a signed integer.
+* A min value is not calculated because it will always
+* be 1 on all machines.
+*/
+ u64 max = min(0x7fffULL,
+ __scale_tsc(kvm_caps.max_tsc_scaling_ratio,
tsc_khz));
+ kvm_caps.max_guest_tsc_khz = max;
+ }
+ kvm_caps.default_tsc_scaling_ratio = 1ULL <<
kvm_caps.tsc_scaling_ratio_frac_bits;
+ kvm_init_msr_list();
return 0;
+out_mmu_exit:
+ kvm_mmu_vendor_module_exit();
out_free_percpu:
free_percpu(user_return_msrs);
out_free_x86_emulator_cache:
@@ -9353,6 +9413,8 @@ int kvm_arch_init(void *opaque)
void kvm_arch_exit(void)
{
+ kvm_unregister_perf_callbacks();
+
#ifdef CONFIG_X86_64
if (hypervisor_is_type(X86_HYPER_MS_HYPERV))
clear_hv_tscchange_cb();
@@ -9368,6 +9430,7 @@ void kvm_arch_exit(void)
irq_work_sync(_irq_work);
cancel_work_sync(_gtod_work);
#endif
+ static_call(kvm_x86_hardware_unsetup)();
kvm_x86_ops.hardware_enable = NULL;
kvm_mmu_vendor_module_exit();
free_percpu(user_return_msrs);
@@ -11957,72 +12020,14 @@ void kvm_arch_hardware_disable(void)
drop_user_return_notifiers();
}
-static inline void kvm_ops_update(struct kvm_x86_init_ops *ops)
-{
- memcpy(_x86_ops, ops->runtime_ops, sizeof(kvm_x86_ops));
-
-#define __KVM_X86_OP(func) \
- static_call_update(kvm_x86_##func, kvm_x86_ops.func);
-#define KVM_X86_OP(func) \
- WARN_ON(!kvm_x86_ops.func); __KVM_X86_OP(func)
-#define KVM_X86_OP_OPTIONAL __KVM_X86_OP
-#define KVM_X86_OP_OPTIONAL_RET0(func) \
- static_call_update(kvm_x86_##func, (void *)kvm_x86_ops.func ? : \
- (void
[PATCH v2 05/50] KVM: s390: Unwind kvm_arch_init() piece-by-piece() if a step fails
In preparation for folding kvm_arch_hardware_setup() into kvm_arch_init(),
unwind initialization one step at a time instead of simply calling
kvm_arch_exit(). Using kvm_arch_exit() regardless of which initialization
step failed relies on all affected state playing nice with being undone
even if said state wasn't first setup. That holds true for state that is
currently configured by kvm_arch_init(), but not for state that's handled
by kvm_arch_hardware_setup(), e.g. calling gmap_unregister_pte_notifier()
without first registering a notifier would result in list corruption due
to attempting to delete an entry that was never added to the list.
Signed-off-by: Sean Christopherson
Reviewed-by: Eric Farman
---
arch/s390/kvm/kvm-s390.c | 21 ++---
1 file changed, 14 insertions(+), 7 deletions(-)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index e4890e04b210..221481a09742 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -498,11 +498,11 @@ int kvm_arch_init(void *opaque)
kvm_s390_dbf_uv = debug_register("kvm-uv", 32, 1, 7 * sizeof(long));
if (!kvm_s390_dbf_uv)
- goto out;
+ goto err_kvm_uv;
if (debug_register_view(kvm_s390_dbf, _sprintf_view) ||
debug_register_view(kvm_s390_dbf_uv, _sprintf_view))
- goto out;
+ goto err_debug_view;
kvm_s390_cpu_feat_init();
@@ -510,25 +510,32 @@ int kvm_arch_init(void *opaque)
rc = kvm_register_device_ops(_flic_ops, KVM_DEV_TYPE_FLIC);
if (rc) {
pr_err("A FLIC registration call failed with rc=%d\n", rc);
- goto out;
+ goto err_flic;
}
if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM)) {
rc = kvm_s390_pci_init();
if (rc) {
pr_err("Unable to allocate AIFT for PCI\n");
- goto out;
+ goto err_pci;
}
}
rc = kvm_s390_gib_init(GAL_ISC);
if (rc)
- goto out;
+ goto err_gib;
return 0;
-out:
- kvm_arch_exit();
+err_gib:
+ if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM))
+ kvm_s390_pci_exit();
+err_pci:
+err_flic:
+err_debug_view:
+ debug_unregister(kvm_s390_dbf_uv);
+err_kvm_uv:
+ debug_unregister(kvm_s390_dbf);
return rc;
}
--
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[PATCH v2 03/50] KVM: Allocate cpus_hardware_enabled after arch hardware setup
Allocate cpus_hardware_enabled after arch hardware setup so that arch
"init" and "hardware setup" are called back-to-back and thus can be
combined in a future patch. cpus_hardware_enabled is never used before
kvm_create_vm(), i.e. doesn't have a dependency with hardware setup and
only needs to be allocated before /dev/kvm is exposed to userspace.
Free the object before the arch hooks are invoked to maintain symmetry,
and so that arch code can move away from the hooks without having to
worry about ordering changes.
Signed-off-by: Sean Christopherson
Reviewed-by: Yuan Yao
---
virt/kvm/kvm_main.c | 14 +++---
1 file changed, 7 insertions(+), 7 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 43e2e4f38151..ded88ad6c2d8 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5862,15 +5862,15 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
if (r)
return r;
+ r = kvm_arch_hardware_setup(opaque);
+ if (r < 0)
+ goto err_hw_setup;
+
if (!zalloc_cpumask_var(_hardware_enabled, GFP_KERNEL)) {
r = -ENOMEM;
goto err_hw_enabled;
}
- r = kvm_arch_hardware_setup(opaque);
- if (r < 0)
- goto out_free_1;
-
c.ret =
c.opaque = opaque;
for_each_online_cpu(cpu) {
@@ -5956,10 +5956,10 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
unregister_reboot_notifier(_reboot_notifier);
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
out_free_2:
- kvm_arch_hardware_unsetup();
-out_free_1:
free_cpumask_var(cpus_hardware_enabled);
err_hw_enabled:
+ kvm_arch_hardware_unsetup();
+err_hw_setup:
kvm_arch_exit();
return r;
}
@@ -5986,9 +5986,9 @@ void kvm_exit(void)
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
on_each_cpu(hardware_disable_nolock, NULL, 1);
kvm_irqfd_exit();
+ free_cpumask_var(cpus_hardware_enabled);
kvm_arch_hardware_unsetup();
kvm_arch_exit();
- free_cpumask_var(cpus_hardware_enabled);
kvm_vfio_ops_exit();
}
EXPORT_SYMBOL_GPL(kvm_exit);
--
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[PATCH v2 06/50] KVM: s390: Move hardware setup/unsetup to init/exit
Now that kvm_arch_hardware_setup() is called immediately after
kvm_arch_init(), fold the guts of kvm_arch_hardware_(un)setup() into
kvm_arch_{init,exit}() as a step towards dropping one of the hooks.
No functional change intended.
Signed-off-by: Sean Christopherson
Reviewed-by: Eric Farman
---
arch/s390/kvm/kvm-s390.c | 23 +--
1 file changed, 13 insertions(+), 10 deletions(-)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 221481a09742..97c7ccd189eb 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -331,21 +331,12 @@ static struct notifier_block kvm_clock_notifier = {
int kvm_arch_hardware_setup(void *opaque)
{
- gmap_notifier.notifier_call = kvm_gmap_notifier;
- gmap_register_pte_notifier(_notifier);
- vsie_gmap_notifier.notifier_call = kvm_s390_vsie_gmap_notifier;
- gmap_register_pte_notifier(_gmap_notifier);
- atomic_notifier_chain_register(_epoch_delta_notifier,
- _clock_notifier);
return 0;
}
void kvm_arch_hardware_unsetup(void)
{
- gmap_unregister_pte_notifier(_notifier);
- gmap_unregister_pte_notifier(_gmap_notifier);
- atomic_notifier_chain_unregister(_epoch_delta_notifier,
-_clock_notifier);
+
}
static void allow_cpu_feat(unsigned long nr)
@@ -525,6 +516,13 @@ int kvm_arch_init(void *opaque)
if (rc)
goto err_gib;
+ gmap_notifier.notifier_call = kvm_gmap_notifier;
+ gmap_register_pte_notifier(_notifier);
+ vsie_gmap_notifier.notifier_call = kvm_s390_vsie_gmap_notifier;
+ gmap_register_pte_notifier(_gmap_notifier);
+ atomic_notifier_chain_register(_epoch_delta_notifier,
+ _clock_notifier);
+
return 0;
err_gib:
@@ -541,6 +539,11 @@ int kvm_arch_init(void *opaque)
void kvm_arch_exit(void)
{
+ gmap_unregister_pte_notifier(_notifier);
+ gmap_unregister_pte_notifier(_gmap_notifier);
+ atomic_notifier_chain_unregister(_epoch_delta_notifier,
+_clock_notifier);
+
kvm_s390_gib_destroy();
if (IS_ENABLED(CONFIG_VFIO_PCI_ZDEV_KVM))
kvm_s390_pci_exit();
--
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[PATCH v2 04/50] KVM: Teardown VFIO ops earlier in kvm_exit()
Move the call to kvm_vfio_ops_exit() further up kvm_exit() to try and
bring some amount of symmetry to the setup order in kvm_init(), and more
importantly so that the arch hooks are invoked dead last by kvm_exit().
This will allow arch code to move away from the arch hooks without any
change in ordering between arch code and common code in kvm_exit().
That kvm_vfio_ops_exit() is called last appears to be 100% arbitrary. It
was bolted on after the fact by commit 571ee1b68598 ("kvm: vfio: fix
unregister kvm_device_ops of vfio"). The nullified kvm_device_ops_table
is also local to kvm_main.c and is used only when there are active VMs,
so unless arch code is doing something truly bizarre, nullifying the
table earlier in kvm_exit() is little more than a nop.
Signed-off-by: Sean Christopherson
Reviewed-by: Cornelia Huck
Reviewed-by: Eric Farman
---
virt/kvm/kvm_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index ded88ad6c2d8..988f7d92db2e 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5980,6 +5980,7 @@ void kvm_exit(void)
for_each_possible_cpu(cpu)
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
kmem_cache_destroy(kvm_vcpu_cache);
+ kvm_vfio_ops_exit();
kvm_async_pf_deinit();
unregister_syscore_ops(_syscore_ops);
unregister_reboot_notifier(_reboot_notifier);
@@ -5989,7 +5990,6 @@ void kvm_exit(void)
free_cpumask_var(cpus_hardware_enabled);
kvm_arch_hardware_unsetup();
kvm_arch_exit();
- kvm_vfio_ops_exit();
}
EXPORT_SYMBOL_GPL(kvm_exit);
--
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[PATCH v2 02/50] KVM: Initialize IRQ FD after arch hardware setup
Move initialization of KVM's IRQ FD workqueue below arch hardware setup
as a step towards consolidating arch "init" and "hardware setup", and
eventually towards dropping the hooks entirely. There is no dependency
on the workqueue being created before hardware setup, the workqueue is
used only when destroying VMs, i.e. only needs to be created before
/dev/kvm is exposed to userspace.
Move the destruction of the workqueue before the arch hooks to maintain
symmetry, and so that arch code can move away from the hooks without
having to worry about ordering changes.
Reword the comment about kvm_irqfd_init() needing to come after
kvm_arch_init() to call out that kvm_arch_init() must come before common
KVM does _anything_, as x86 very subtly relies on that behavior to deal
with multiple calls to kvm_init(), e.g. if userspace attempts to load
kvm_amd.ko and kvm_intel.ko. Tag the code with a FIXME, as x86's subtle
requirement is gross, and invoking an arch callback as the very first
action in a helper that is called only from arch code is silly.
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 37 ++---
1 file changed, 18 insertions(+), 19 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index b60abb03606b..43e2e4f38151 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5852,24 +5852,19 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
int r;
int cpu;
+ /*
+* FIXME: Get rid of kvm_arch_init(), vendor code should call arch code
+* directly. Note, kvm_arch_init() _must_ be called before anything
+* else as x86 relies on checks buried in kvm_arch_init() to guard
+* against multiple calls to kvm_init().
+*/
r = kvm_arch_init(opaque);
if (r)
- goto out_fail;
-
- /*
-* kvm_arch_init makes sure there's at most one caller
-* for architectures that support multiple implementations,
-* like intel and amd on x86.
-* kvm_arch_init must be called before kvm_irqfd_init to avoid creating
-* conflicts in case kvm is already setup for another implementation.
-*/
- r = kvm_irqfd_init();
- if (r)
- goto out_irqfd;
+ return r;
if (!zalloc_cpumask_var(_hardware_enabled, GFP_KERNEL)) {
r = -ENOMEM;
- goto out_free_0;
+ goto err_hw_enabled;
}
r = kvm_arch_hardware_setup(opaque);
@@ -5913,9 +5908,13 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
}
}
+ r = kvm_irqfd_init();
+ if (r)
+ goto err_irqfd;
+
r = kvm_async_pf_init();
if (r)
- goto out_free_4;
+ goto err_async_pf;
kvm_chardev_ops.owner = module;
@@ -5946,6 +5945,9 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
kvm_vfio_ops_exit();
err_vfio:
kvm_async_pf_deinit();
+err_async_pf:
+ kvm_irqfd_exit();
+err_irqfd:
out_free_4:
for_each_possible_cpu(cpu)
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
@@ -5957,11 +5959,8 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
kvm_arch_hardware_unsetup();
out_free_1:
free_cpumask_var(cpus_hardware_enabled);
-out_free_0:
- kvm_irqfd_exit();
-out_irqfd:
+err_hw_enabled:
kvm_arch_exit();
-out_fail:
return r;
}
EXPORT_SYMBOL_GPL(kvm_init);
@@ -5986,9 +5985,9 @@ void kvm_exit(void)
unregister_reboot_notifier(_reboot_notifier);
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING);
on_each_cpu(hardware_disable_nolock, NULL, 1);
+ kvm_irqfd_exit();
kvm_arch_hardware_unsetup();
kvm_arch_exit();
- kvm_irqfd_exit();
free_cpumask_var(cpus_hardware_enabled);
kvm_vfio_ops_exit();
}
--
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[PATCH v2 00/50] KVM: Rework kvm_init() and hardware enabling
The main theme of this series is to kill off kvm_arch_init(),
kvm_arch_hardware_(un)setup(), and kvm_arch_check_processor_compat(), which
all originated in x86 code from way back when, and needlessly complicate
both common KVM code and architecture code. E.g. many architectures don't
mark functions/data as __init/__ro_after_init purely because kvm_init()
isn't marked __init to support x86's separate vendor modules.
The idea/hope is that with those hooks gone (moved to arch code), it will
be easier for x86 (and other architectures) to modify their module init
sequences as needed without having to fight common KVM code. E.g. I'm
hoping that ARM can build on this to simplify its hardware enabling logic,
especially the pKVM side of things.
There are bug fixes throughout this series. They are more scattered than
I would usually prefer, but getting the sequencing correct was a gigantic
pain for many of the x86 fixes due to needing to fix common code in order
for the x86 fix to have any meaning. And while the bugs are often fatal,
they aren't all that interesting for most users as they either require a
malicious admin or broken hardware, i.e. aren't likely to be encountered
by the vast majority of KVM users. So unless someone _really_ wants a
particular fix isolated for backporting, I'm not planning on shuffling
patches.
v2:
- Collect reviews/acks.
- Reset eVMCS controls in VP assist page when disabling hardware. [Vitaly]
- Clean up labels in kvm_init(). [Chao]
- Fix a goof where VMX compat checks used boot_cpu_has. [Kai]
- Reorder patches and/or tweak changelogs to not require time travel. [Paolo,
Kai]
- Rewrite the changelog for the patch to move ARM away from kvm_arch_init()
to call out that it fixes theoretical bugs. [Philippe]
- Document why it's safe to allow preemption and/or migration when
accessing kvm_usage_count.
v1: https://lore.kernel.org/all/20221102231911.3107438-1-sea...@google.com
Chao Gao (3):
KVM: x86: Do compatibility checks when onlining CPU
KVM: Rename and move CPUHP_AP_KVM_STARTING to ONLINE section
KVM: Disable CPU hotplug during hardware enabling/disabling
Isaku Yamahata (3):
KVM: Drop kvm_count_lock and instead protect kvm_usage_count with
kvm_lock
KVM: Remove on_each_cpu(hardware_disable_nolock) in kvm_exit()
KVM: Make hardware_enable_failed a local variable in the "enable all"
path
Marc Zyngier (1):
KVM: arm64: Simplify the CPUHP logic
Sean Christopherson (43):
KVM: Register /dev/kvm as the _very_ last thing during initialization
KVM: Initialize IRQ FD after arch hardware setup
KVM: Allocate cpus_hardware_enabled after arch hardware setup
KVM: Teardown VFIO ops earlier in kvm_exit()
KVM: s390: Unwind kvm_arch_init() piece-by-piece() if a step fails
KVM: s390: Move hardware setup/unsetup to init/exit
KVM: x86: Do timer initialization after XCR0 configuration
KVM: x86: Move hardware setup/unsetup to init/exit
KVM: Drop arch hardware (un)setup hooks
KVM: VMX: Reset eVMCS controls in VP assist page during hardware
disabling
KVM: VMX: Don't bother disabling eVMCS static key on module exit
KVM: VMX: Move Hyper-V eVMCS initialization to helper
KVM: x86: Move guts of kvm_arch_init() to standalone helper
KVM: VMX: Do _all_ initialization before exposing /dev/kvm to
userspace
KVM: x86: Serialize vendor module initialization (hardware setup)
KVM: arm64: Free hypervisor allocations if vector slot init fails
KVM: arm64: Unregister perf callbacks if hypervisor finalization fails
KVM: arm64: Do arm/arch initialization without bouncing through
kvm_init()
KVM: arm64: Mark kvm_arm_init() and its unique descendants as __init
KVM: MIPS: Hardcode callbacks to hardware virtualization extensions
KVM: MIPS: Setup VZ emulation? directly from kvm_mips_init()
KVM: MIPS: Register die notifier prior to kvm_init()
KVM: RISC-V: Do arch init directly in riscv_kvm_init()
KVM: RISC-V: Tag init functions and data with __init, __ro_after_init
KVM: PPC: Move processor compatibility check to module init
KVM: s390: Do s390 specific init without bouncing through kvm_init()
KVM: s390: Mark __kvm_s390_init() and its descendants as __init
KVM: Drop kvm_arch_{init,exit}() hooks
KVM: VMX: Make VMCS configuration/capabilities structs read-only after
init
KVM: x86: Do CPU compatibility checks in x86 code
KVM: Drop kvm_arch_check_processor_compat() hook
KVM: x86: Use KBUILD_MODNAME to specify vendor module name
KVM: x86: Unify pr_fmt to use module name for all KVM modules
KVM: VMX: Use current CPU's info to perform "disabled by BIOS?" checks
KVM: x86: Do VMX/SVM support checks directly in vendor code
KVM: VMX: Shuffle support checks and hardware enabling code around
KVM: SVM: Check for SVM support in CPU compatibility checks
KVM: x86: Move CPU compat checks hook to kvm_x86_ops (from
kvm_x86_init_ops)
KVM: Ensure CPU is stable during low level hardware enable/disable
KVM: Use a per-CPU
[PATCH v2 01/50] KVM: Register /dev/kvm as the _very_ last thing during initialization
Register /dev/kvm, i.e. expose KVM to userspace, only after all other
setup has completed. Once /dev/kvm is exposed, userspace can start
invoking KVM ioctls, creating VMs, etc... If userspace creates a VM
before KVM is done with its configuration, bad things may happen, e.g.
KVM will fail to properly migrate vCPU state if a VM is created before
KVM has registered preemption notifiers.
Cc: sta...@vger.kernel.org
Signed-off-by: Sean Christopherson
---
virt/kvm/kvm_main.c | 31 ++-
1 file changed, 22 insertions(+), 9 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1782c4555d94..b60abb03606b 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -5919,12 +5919,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
kvm_chardev_ops.owner = module;
- r = misc_register(_dev);
- if (r) {
- pr_err("kvm: misc device register failed\n");
- goto out_unreg;
- }
-
register_syscore_ops(_syscore_ops);
kvm_preempt_ops.sched_in = kvm_sched_in;
@@ -5933,11 +5927,24 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned
vcpu_align,
kvm_init_debug();
r = kvm_vfio_ops_init();
- WARN_ON(r);
+ if (WARN_ON_ONCE(r))
+ goto err_vfio;
+
+ /*
+* Registration _must_ be the very last thing done, as this exposes
+* /dev/kvm to userspace, i.e. all infrastructure must be setup!
+*/
+ r = misc_register(_dev);
+ if (r) {
+ pr_err("kvm: misc device register failed\n");
+ goto err_register;
+ }
return 0;
-out_unreg:
+err_register:
+ kvm_vfio_ops_exit();
+err_vfio:
kvm_async_pf_deinit();
out_free_4:
for_each_possible_cpu(cpu)
@@ -5963,8 +5970,14 @@ void kvm_exit(void)
{
int cpu;
- debugfs_remove_recursive(kvm_debugfs_dir);
+ /*
+* Note, unregistering /dev/kvm doesn't strictly need to come first,
+* fops_get(), a.k.a. try_module_get(), prevents acquiring references
+* to KVM while the module is being stopped.
+*/
misc_deregister(_dev);
+
+ debugfs_remove_recursive(kvm_debugfs_dir);
for_each_possible_cpu(cpu)
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
kmem_cache_destroy(kvm_vcpu_cache);
--
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Re: [PATCH 32/44] KVM: x86: Unify pr_fmt to use module name for all KVM modules
On Thu, Nov 10, 2022, Sean Christopherson wrote: > On Thu, Nov 10, 2022, Robert Hoo wrote: > > After this patch set, still find some printk()s left in arch/x86/kvm/*, > > consider clean all of them up? > > Hmm, yeah, I suppose at this point it makes sense to tack on a patch to clean > them up. Actually, I'm going to pass on this for now. The series is already too big. I'll add this to my todo list for the future. ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
Re: [PATCH 0/4] KVM: arm64: Parallel access faults
On Tue, 29 Nov 2022 19:19:42 +, Oliver Upton wrote: > > When I implemented the parallel faults series I was mostly focused on > improving the performance of 8.1+ implementations which bring us > FEAT_HAFDBS. In so doing, I failed to put access faults on the read side > of the MMU lock. > > Anyhow, this small series adds support for handling access faults in > parallel, piling on top of the infrastructure from the first parallel > faults series. As most large systems I'm aware of are 8.1+ anyway, I > don't expect this series to provide significant uplift beyond some > oddball machines Marc has lying around. Don't get me wrong, I'd love to > have a D05 to play with too... Hey, that puts the whole fruity range of machines in the oddball department too, as they don't implement any of HAFDBS! The feature being optional, I wouldn't be surprised if others would either not implement it (or disable it to hide that it is b0rk3n...). M. -- Without deviation from the norm, progress is not possible. ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
Re: [PATCH 2/4] KVM: arm64: Don't serialize if the access flag isn't set
On Wed, 30 Nov 2022 01:23:20 +, Ricardo Koller wrote: > > On Tue, Nov 29, 2022 at 09:15:21PM +, Oliver Upton wrote: > > Hi Ricardo, > > > > Thanks for having a look. > > > > On Tue, Nov 29, 2022 at 12:52:12PM -0800, Ricardo Koller wrote: > > > On Tue, Nov 29, 2022 at 07:19:44PM +, Oliver Upton wrote: > > > > [...] > > > > > > + ret = stage2_update_leaf_attrs(pgt, addr, 1, > > > > KVM_PTE_LEAF_ATTR_LO_S2_AF, 0, > > > > + , NULL, 0); > > > > + if (!ret) > > > > + dsb(ishst); > > > > > > At the moment, the only reason for stage2_update_leaf_attrs() to not > > > update the PTE is if it's not valid: > > > > > > if (!kvm_pte_valid(pte)) > > > return 0; > > > > > > I guess you could check that as well: > > > > > > + if (!ret || kvm_pte_valid(pte)) > > > + dsb(ishst); > > > > Thanks for catching this. > > > > Instead of pivoting on the returned PTE value, how about we return > > -EAGAIN from the early return in stage2_attr_walker()? It would better > > match the pattern used elsewhere in the pgtable code. > > That works, although I would use another return code (e.g., EINVAL)? as > that's not exactly a "try again" type of error. EINVAL usually is an indication of something that went horribly wrong. But is that really a failure mode? Here, failing to update the PTE should not be considered a failure, but just a benign race: access fault being taken on a CPU and the page being evicted on another (not unlikely, as the page was marked old before). And if I'm correct above, this is definitely a "try again" situation: you probably won't take the same type of fault the second time though. Thanks, M. -- Without deviation from the norm, progress is not possible. ___ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
