Re: [PATCH v6 17/21] KVM: arm64: Allow userspace to configure a guest's counter-timer offset
On Tue, 10 Aug 2021 18:55:12 +0100,
Oliver Upton wrote:
>
> On Tue, Aug 10, 2021 at 3:56 AM Marc Zyngier wrote:
> >
> > On Wed, 04 Aug 2021 09:58:15 +0100,
> > Oliver Upton wrote:
[...]
> > > diff --git a/include/clocksource/arm_arch_timer.h
> > > b/include/clocksource/arm_arch_timer.h
> > > index 73c7139c866f..7252ffa3d675 100644
> > > --- a/include/clocksource/arm_arch_timer.h
> > > +++ b/include/clocksource/arm_arch_timer.h
> > > @@ -21,6 +21,7 @@
> > > #define CNTHCTL_EVNTEN (1 << 2)
> > > #define CNTHCTL_EVNTDIR (1 << 3)
> > > #define CNTHCTL_EVNTI(0xF << 4)
> > > +#define CNTHCTL_ECV (1 << 12)
> > >
> > > enum arch_timer_reg {
> > > ARCH_TIMER_REG_CTRL,
> >
> > You also want to document that SCR_EL3.ECVEn has to be set to 1 for
> > this to work (see Documentation/arm64/booting.txt). And if it isn't,
> > the firmware better handle the CNTPOFF_EL2 traps correctly...
>
> I'll grab the popcorn now ;-) Adding docs for this, good idea.
>
> > What firmware did you use for this? I think we need to update the boot
> > wrapper, but that's something that can be done in parallel.
>
> I had actually just done a direct boot from ARM-TF -> Linux, nothing
> else in between.
Ah, right. I tend to use the boot-wrapper[1] to build a single binary
that contains the 'boot loader', DT and kernel. Using ATF is probably
more representative of the final thing, but the boot-wrapper is dead
easy to hack on...
Thanks,
M.
[1] git://git.kernel.org/pub/scm/linux/kernel/git/mark/boot-wrapper-aarch64.git
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Re: [PATCH v6 17/21] KVM: arm64: Allow userspace to configure a guest's counter-timer offset
On Tue, Aug 10, 2021 at 3:56 AM Marc Zyngier wrote:
>
> On Wed, 04 Aug 2021 09:58:15 +0100,
> Oliver Upton wrote:
> >
> > Presently, KVM provides no facilities for correctly migrating a guest
> > that depends on the physical counter-timer. Whie most guests (barring
>
> nit: While
Ack.
>
> > NV, of course) should not depend on the physical counter-timer, an
> > operator may wish to provide a consistent view of the physical
> > counter-timer across migrations.
> >
> > Provide userspace with a new vCPU attribute to modify the guest
> > counter-timer offset. Unlike KVM_REG_ARM_TIMER_OFFSET, this attribute is
> > hidden from the guest's architectural state. The value offsets *both*
> > the virtual and physical counter-timer views for the guest. Only support
> > this attribute on ECV systems as ECV is required for hardware offsetting
> > of the physical counter-timer.
> >
> > Signed-off-by: Oliver Upton
> > ---
> > Documentation/virt/kvm/devices/vcpu.rst | 28 ++
> > arch/arm64/include/asm/kvm_asm.h| 2 +
> > arch/arm64/include/asm/sysreg.h | 2 +
> > arch/arm64/include/uapi/asm/kvm.h | 1 +
> > arch/arm64/kvm/arch_timer.c | 122 +++-
> > arch/arm64/kvm/hyp/nvhe/hyp-main.c | 6 ++
> > arch/arm64/kvm/hyp/nvhe/timer-sr.c | 5 +
> > arch/arm64/kvm/hyp/vhe/timer-sr.c | 5 +
> > include/clocksource/arm_arch_timer.h| 1 +
> > 9 files changed, 169 insertions(+), 3 deletions(-)
> >
> > diff --git a/Documentation/virt/kvm/devices/vcpu.rst
> > b/Documentation/virt/kvm/devices/vcpu.rst
> > index 3b399d727c11..3ba35b9d9d03 100644
> > --- a/Documentation/virt/kvm/devices/vcpu.rst
> > +++ b/Documentation/virt/kvm/devices/vcpu.rst
> > @@ -139,6 +139,34 @@ configured values on other VCPUs. Userspace should
> > configure the interrupt
> > numbers on at least one VCPU after creating all VCPUs and before running
> > any
> > VCPUs.
> >
> > +2.2. ATTRIBUTE: KVM_ARM_VCPU_TIMER_OFFSET
> > +-
> > +
> > +:Parameters: in kvm_device_attr.addr the address for the timer offset is a
> > + pointer to a __u64
> > +
> > +Returns:
> > +
> > + === ==
> > + -EFAULT Error reading/writing the provided
> > + parameter address
> > + -ENXIO Timer offsetting not implemented
> > + === ==
> > +
> > +Specifies the guest's counter-timer offset from the host's virtual counter.
> > +The guest's physical counter value is then derived by the following
> > +equation:
> > +
> > + guest_cntpct = host_cntvct - KVM_ARM_VCPU_TIMER_OFFSET
> > +
> > +The guest's virtual counter value is derived by the following equation:
> > +
> > + guest_cntvct = host_cntvct - KVM_REG_ARM_TIMER_OFFSET
> > + - KVM_ARM_VCPU_TIMER_OFFSET
> > +
> > +KVM does not allow the use of varying offset values for different vCPUs;
> > +the last written offset value will be broadcasted to all vCPUs in a VM.
> > +
> > 3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
> > ==
> >
> > diff --git a/arch/arm64/include/asm/kvm_asm.h
> > b/arch/arm64/include/asm/kvm_asm.h
> > index 9f0bf2109be7..ab1c8fdb0177 100644
> > --- a/arch/arm64/include/asm/kvm_asm.h
> > +++ b/arch/arm64/include/asm/kvm_asm.h
> > @@ -65,6 +65,7 @@
> > #define __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize 19
> > #define __KVM_HOST_SMCCC_FUNC___pkvm_mark_hyp20
> > #define __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc21
> > +#define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntpoff22
> >
> > #ifndef __ASSEMBLY__
> >
> > @@ -200,6 +201,7 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu
> > *mmu, phys_addr_t ipa,
> > extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu);
> >
> > extern void __kvm_timer_set_cntvoff(u64 cntvoff);
> > +extern void __kvm_timer_set_cntpoff(u64 cntpoff);
> >
> > extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
> >
> > diff --git a/arch/arm64/include/asm/sysreg.h
> > b/arch/arm64/include/asm/sysreg.h
> > index 4dfc44066dfb..c34672aa65b9 100644
> > --- a/arch/arm64/include/asm/sysreg.h
> > +++ b/arch/arm64/include/asm/sysreg.h
> > @@ -586,6 +586,8 @@
> > #define SYS_ICH_LR14_EL2 __SYS__LR8_EL2(6)
> > #define SYS_ICH_LR15_EL2 __SYS__LR8_EL2(7)
> >
> > +#define SYS_CNTPOFF_EL2 sys_reg(3, 4, 14, 0, 6)
> > +
> > /* VHE encodings for architectural EL0/1 system registers */
> > #define SYS_SCTLR_EL12 sys_reg(3, 5, 1, 0, 0)
> > #define SYS_CPACR_EL12 sys_reg(3, 5, 1, 0, 2)
> > diff --git a/arch/arm64/include/uapi/asm/kvm.h
> > b/arch/arm64/include/uapi/asm/kvm.h
> > index 949a31bc10f0..15150f8224a1 100644
> > --- a/arch/arm64/include/uapi/asm/kvm.h
> > +++ b/arch/arm64/include/uapi/asm/kvm.h
> > @@ -366,6 +366,7 @@ struct kvm_arm_copy_mte_tags {
>
Re: [PATCH v6 17/21] KVM: arm64: Allow userspace to configure a guest's counter-timer offset
On Wed, 04 Aug 2021 09:58:15 +0100,
Oliver Upton wrote:
>
> Presently, KVM provides no facilities for correctly migrating a guest
> that depends on the physical counter-timer. Whie most guests (barring
nit: While
> NV, of course) should not depend on the physical counter-timer, an
> operator may wish to provide a consistent view of the physical
> counter-timer across migrations.
>
> Provide userspace with a new vCPU attribute to modify the guest
> counter-timer offset. Unlike KVM_REG_ARM_TIMER_OFFSET, this attribute is
> hidden from the guest's architectural state. The value offsets *both*
> the virtual and physical counter-timer views for the guest. Only support
> this attribute on ECV systems as ECV is required for hardware offsetting
> of the physical counter-timer.
>
> Signed-off-by: Oliver Upton
> ---
> Documentation/virt/kvm/devices/vcpu.rst | 28 ++
> arch/arm64/include/asm/kvm_asm.h| 2 +
> arch/arm64/include/asm/sysreg.h | 2 +
> arch/arm64/include/uapi/asm/kvm.h | 1 +
> arch/arm64/kvm/arch_timer.c | 122 +++-
> arch/arm64/kvm/hyp/nvhe/hyp-main.c | 6 ++
> arch/arm64/kvm/hyp/nvhe/timer-sr.c | 5 +
> arch/arm64/kvm/hyp/vhe/timer-sr.c | 5 +
> include/clocksource/arm_arch_timer.h| 1 +
> 9 files changed, 169 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/virt/kvm/devices/vcpu.rst
> b/Documentation/virt/kvm/devices/vcpu.rst
> index 3b399d727c11..3ba35b9d9d03 100644
> --- a/Documentation/virt/kvm/devices/vcpu.rst
> +++ b/Documentation/virt/kvm/devices/vcpu.rst
> @@ -139,6 +139,34 @@ configured values on other VCPUs. Userspace should
> configure the interrupt
> numbers on at least one VCPU after creating all VCPUs and before running any
> VCPUs.
>
> +2.2. ATTRIBUTE: KVM_ARM_VCPU_TIMER_OFFSET
> +-
> +
> +:Parameters: in kvm_device_attr.addr the address for the timer offset is a
> + pointer to a __u64
> +
> +Returns:
> +
> + === ==
> + -EFAULT Error reading/writing the provided
> + parameter address
> + -ENXIO Timer offsetting not implemented
> + === ==
> +
> +Specifies the guest's counter-timer offset from the host's virtual counter.
> +The guest's physical counter value is then derived by the following
> +equation:
> +
> + guest_cntpct = host_cntvct - KVM_ARM_VCPU_TIMER_OFFSET
> +
> +The guest's virtual counter value is derived by the following equation:
> +
> + guest_cntvct = host_cntvct - KVM_REG_ARM_TIMER_OFFSET
> + - KVM_ARM_VCPU_TIMER_OFFSET
> +
> +KVM does not allow the use of varying offset values for different vCPUs;
> +the last written offset value will be broadcasted to all vCPUs in a VM.
> +
> 3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
> ==
>
> diff --git a/arch/arm64/include/asm/kvm_asm.h
> b/arch/arm64/include/asm/kvm_asm.h
> index 9f0bf2109be7..ab1c8fdb0177 100644
> --- a/arch/arm64/include/asm/kvm_asm.h
> +++ b/arch/arm64/include/asm/kvm_asm.h
> @@ -65,6 +65,7 @@
> #define __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize 19
> #define __KVM_HOST_SMCCC_FUNC___pkvm_mark_hyp20
> #define __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc21
> +#define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntpoff22
>
> #ifndef __ASSEMBLY__
>
> @@ -200,6 +201,7 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu
> *mmu, phys_addr_t ipa,
> extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu);
>
> extern void __kvm_timer_set_cntvoff(u64 cntvoff);
> +extern void __kvm_timer_set_cntpoff(u64 cntpoff);
>
> extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
>
> diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> index 4dfc44066dfb..c34672aa65b9 100644
> --- a/arch/arm64/include/asm/sysreg.h
> +++ b/arch/arm64/include/asm/sysreg.h
> @@ -586,6 +586,8 @@
> #define SYS_ICH_LR14_EL2 __SYS__LR8_EL2(6)
> #define SYS_ICH_LR15_EL2 __SYS__LR8_EL2(7)
>
> +#define SYS_CNTPOFF_EL2 sys_reg(3, 4, 14, 0, 6)
> +
> /* VHE encodings for architectural EL0/1 system registers */
> #define SYS_SCTLR_EL12 sys_reg(3, 5, 1, 0, 0)
> #define SYS_CPACR_EL12 sys_reg(3, 5, 1, 0, 2)
> diff --git a/arch/arm64/include/uapi/asm/kvm.h
> b/arch/arm64/include/uapi/asm/kvm.h
> index 949a31bc10f0..15150f8224a1 100644
> --- a/arch/arm64/include/uapi/asm/kvm.h
> +++ b/arch/arm64/include/uapi/asm/kvm.h
> @@ -366,6 +366,7 @@ struct kvm_arm_copy_mte_tags {
> #define KVM_ARM_VCPU_TIMER_CTRL 1
> #define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
> #define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1
> +#define KVM_ARM_VCPU_TIMER_OFFSET 2
> #define KVM_ARM_VCPU_PVTIME_CTRL 2
> #define
Re: [PATCH v6 17/21] KVM: arm64: Allow userspace to configure a guest's counter-timer offset
On Wed, Aug 4, 2021 at 3:17 AM Andrew Jones wrote:
> > diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
> > index a8815b09da3e..f15058612994 100644
> > --- a/arch/arm64/kvm/arch_timer.c
> > +++ b/arch/arm64/kvm/arch_timer.c
> > @@ -85,11 +85,15 @@ u64 timer_get_cval(struct arch_timer_context *ctxt)
> > static u64 timer_get_offset(struct arch_timer_context *ctxt)
> > {
> > struct kvm_vcpu *vcpu = ctxt->vcpu;
> > + struct arch_timer_cpu *timer = vcpu_timer(vcpu);
>
> This new timer variable doesn't appear to get used.
Ooops, this is stale. Thanks for catching that.
>
> Reviewed-by: Andrew Jones
>
Thanks for the quick review!
--
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[PATCH v6 17/21] KVM: arm64: Allow userspace to configure a guest's counter-timer offset
Presently, KVM provides no facilities for correctly migrating a guest
that depends on the physical counter-timer. Whie most guests (barring
NV, of course) should not depend on the physical counter-timer, an
operator may wish to provide a consistent view of the physical
counter-timer across migrations.
Provide userspace with a new vCPU attribute to modify the guest
counter-timer offset. Unlike KVM_REG_ARM_TIMER_OFFSET, this attribute is
hidden from the guest's architectural state. The value offsets *both*
the virtual and physical counter-timer views for the guest. Only support
this attribute on ECV systems as ECV is required for hardware offsetting
of the physical counter-timer.
Signed-off-by: Oliver Upton
---
Documentation/virt/kvm/devices/vcpu.rst | 28 ++
arch/arm64/include/asm/kvm_asm.h| 2 +
arch/arm64/include/asm/sysreg.h | 2 +
arch/arm64/include/uapi/asm/kvm.h | 1 +
arch/arm64/kvm/arch_timer.c | 122 +++-
arch/arm64/kvm/hyp/nvhe/hyp-main.c | 6 ++
arch/arm64/kvm/hyp/nvhe/timer-sr.c | 5 +
arch/arm64/kvm/hyp/vhe/timer-sr.c | 5 +
include/clocksource/arm_arch_timer.h| 1 +
9 files changed, 169 insertions(+), 3 deletions(-)
diff --git a/Documentation/virt/kvm/devices/vcpu.rst
b/Documentation/virt/kvm/devices/vcpu.rst
index 3b399d727c11..3ba35b9d9d03 100644
--- a/Documentation/virt/kvm/devices/vcpu.rst
+++ b/Documentation/virt/kvm/devices/vcpu.rst
@@ -139,6 +139,34 @@ configured values on other VCPUs. Userspace should
configure the interrupt
numbers on at least one VCPU after creating all VCPUs and before running any
VCPUs.
+2.2. ATTRIBUTE: KVM_ARM_VCPU_TIMER_OFFSET
+-
+
+:Parameters: in kvm_device_attr.addr the address for the timer offset is a
+ pointer to a __u64
+
+Returns:
+
+=== ==
+-EFAULT Error reading/writing the provided
+parameter address
+-ENXIO Timer offsetting not implemented
+=== ==
+
+Specifies the guest's counter-timer offset from the host's virtual counter.
+The guest's physical counter value is then derived by the following
+equation:
+
+ guest_cntpct = host_cntvct - KVM_ARM_VCPU_TIMER_OFFSET
+
+The guest's virtual counter value is derived by the following equation:
+
+ guest_cntvct = host_cntvct - KVM_REG_ARM_TIMER_OFFSET
+ - KVM_ARM_VCPU_TIMER_OFFSET
+
+KVM does not allow the use of varying offset values for different vCPUs;
+the last written offset value will be broadcasted to all vCPUs in a VM.
+
3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
==
diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index 9f0bf2109be7..ab1c8fdb0177 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -65,6 +65,7 @@
#define __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize 19
#define __KVM_HOST_SMCCC_FUNC___pkvm_mark_hyp 20
#define __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc 21
+#define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntpoff 22
#ifndef __ASSEMBLY__
@@ -200,6 +201,7 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu
*mmu, phys_addr_t ipa,
extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu);
extern void __kvm_timer_set_cntvoff(u64 cntvoff);
+extern void __kvm_timer_set_cntpoff(u64 cntpoff);
extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 4dfc44066dfb..c34672aa65b9 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -586,6 +586,8 @@
#define SYS_ICH_LR14_EL2 __SYS__LR8_EL2(6)
#define SYS_ICH_LR15_EL2 __SYS__LR8_EL2(7)
+#define SYS_CNTPOFF_EL2sys_reg(3, 4, 14, 0, 6)
+
/* VHE encodings for architectural EL0/1 system registers */
#define SYS_SCTLR_EL12 sys_reg(3, 5, 1, 0, 0)
#define SYS_CPACR_EL12 sys_reg(3, 5, 1, 0, 2)
diff --git a/arch/arm64/include/uapi/asm/kvm.h
b/arch/arm64/include/uapi/asm/kvm.h
index 949a31bc10f0..15150f8224a1 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -366,6 +366,7 @@ struct kvm_arm_copy_mte_tags {
#define KVM_ARM_VCPU_TIMER_CTRL1
#define KVM_ARM_VCPU_TIMER_IRQ_VTIMER0
#define KVM_ARM_VCPU_TIMER_IRQ_PTIMER1
+#define KVM_ARM_VCPU_TIMER_OFFSET2
#define KVM_ARM_VCPU_PVTIME_CTRL 2
#define KVM_ARM_VCPU_PVTIME_IPA 0
diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index a8815b09da3e..f15058612994 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -85,11 +85,15 @@ u64 timer_get_cval(struct arch_timer_context *ctxt)
static u64
Re: [PATCH v6 17/21] KVM: arm64: Allow userspace to configure a guest's counter-timer offset
On Wed, Aug 04, 2021 at 08:58:15AM +, Oliver Upton wrote:
> Presently, KVM provides no facilities for correctly migrating a guest
> that depends on the physical counter-timer. Whie most guests (barring
> NV, of course) should not depend on the physical counter-timer, an
> operator may wish to provide a consistent view of the physical
> counter-timer across migrations.
>
> Provide userspace with a new vCPU attribute to modify the guest
> counter-timer offset. Unlike KVM_REG_ARM_TIMER_OFFSET, this attribute is
> hidden from the guest's architectural state. The value offsets *both*
> the virtual and physical counter-timer views for the guest. Only support
> this attribute on ECV systems as ECV is required for hardware offsetting
> of the physical counter-timer.
>
> Signed-off-by: Oliver Upton
> ---
> Documentation/virt/kvm/devices/vcpu.rst | 28 ++
> arch/arm64/include/asm/kvm_asm.h| 2 +
> arch/arm64/include/asm/sysreg.h | 2 +
> arch/arm64/include/uapi/asm/kvm.h | 1 +
> arch/arm64/kvm/arch_timer.c | 122 +++-
> arch/arm64/kvm/hyp/nvhe/hyp-main.c | 6 ++
> arch/arm64/kvm/hyp/nvhe/timer-sr.c | 5 +
> arch/arm64/kvm/hyp/vhe/timer-sr.c | 5 +
> include/clocksource/arm_arch_timer.h| 1 +
> 9 files changed, 169 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/virt/kvm/devices/vcpu.rst
> b/Documentation/virt/kvm/devices/vcpu.rst
> index 3b399d727c11..3ba35b9d9d03 100644
> --- a/Documentation/virt/kvm/devices/vcpu.rst
> +++ b/Documentation/virt/kvm/devices/vcpu.rst
> @@ -139,6 +139,34 @@ configured values on other VCPUs. Userspace should
> configure the interrupt
> numbers on at least one VCPU after creating all VCPUs and before running any
> VCPUs.
>
> +2.2. ATTRIBUTE: KVM_ARM_VCPU_TIMER_OFFSET
> +-
> +
> +:Parameters: in kvm_device_attr.addr the address for the timer offset is a
> + pointer to a __u64
> +
> +Returns:
> +
> + === ==
> + -EFAULT Error reading/writing the provided
> + parameter address
> + -ENXIO Timer offsetting not implemented
> + === ==
> +
> +Specifies the guest's counter-timer offset from the host's virtual counter.
> +The guest's physical counter value is then derived by the following
> +equation:
> +
> + guest_cntpct = host_cntvct - KVM_ARM_VCPU_TIMER_OFFSET
> +
> +The guest's virtual counter value is derived by the following equation:
> +
> + guest_cntvct = host_cntvct - KVM_REG_ARM_TIMER_OFFSET
> + - KVM_ARM_VCPU_TIMER_OFFSET
> +
> +KVM does not allow the use of varying offset values for different vCPUs;
> +the last written offset value will be broadcasted to all vCPUs in a VM.
> +
> 3. GROUP: KVM_ARM_VCPU_PVTIME_CTRL
> ==
>
> diff --git a/arch/arm64/include/asm/kvm_asm.h
> b/arch/arm64/include/asm/kvm_asm.h
> index 9f0bf2109be7..ab1c8fdb0177 100644
> --- a/arch/arm64/include/asm/kvm_asm.h
> +++ b/arch/arm64/include/asm/kvm_asm.h
> @@ -65,6 +65,7 @@
> #define __KVM_HOST_SMCCC_FUNC___pkvm_prot_finalize 19
> #define __KVM_HOST_SMCCC_FUNC___pkvm_mark_hyp20
> #define __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc21
> +#define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntpoff22
>
> #ifndef __ASSEMBLY__
>
> @@ -200,6 +201,7 @@ extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu
> *mmu, phys_addr_t ipa,
> extern void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu);
>
> extern void __kvm_timer_set_cntvoff(u64 cntvoff);
> +extern void __kvm_timer_set_cntpoff(u64 cntpoff);
>
> extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
>
> diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> index 4dfc44066dfb..c34672aa65b9 100644
> --- a/arch/arm64/include/asm/sysreg.h
> +++ b/arch/arm64/include/asm/sysreg.h
> @@ -586,6 +586,8 @@
> #define SYS_ICH_LR14_EL2 __SYS__LR8_EL2(6)
> #define SYS_ICH_LR15_EL2 __SYS__LR8_EL2(7)
>
> +#define SYS_CNTPOFF_EL2 sys_reg(3, 4, 14, 0, 6)
> +
> /* VHE encodings for architectural EL0/1 system registers */
> #define SYS_SCTLR_EL12 sys_reg(3, 5, 1, 0, 0)
> #define SYS_CPACR_EL12 sys_reg(3, 5, 1, 0, 2)
> diff --git a/arch/arm64/include/uapi/asm/kvm.h
> b/arch/arm64/include/uapi/asm/kvm.h
> index 949a31bc10f0..15150f8224a1 100644
> --- a/arch/arm64/include/uapi/asm/kvm.h
> +++ b/arch/arm64/include/uapi/asm/kvm.h
> @@ -366,6 +366,7 @@ struct kvm_arm_copy_mte_tags {
> #define KVM_ARM_VCPU_TIMER_CTRL 1
> #define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
> #define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1
> +#define KVM_ARM_VCPU_TIMER_OFFSET 2
> #define KVM_ARM_VCPU_PVTIME_CTRL 2
> #define
