Re: [RFC v3 00/10] Provide the EL1 physical timer to the VM

[Christoffer Dall]

On Fri, Feb 3, 2017 at 2:14 PM, Jintack Lim  wrote:
> On Fri, Feb 3, 2017 at 7:33 AM, Christoffer Dall  wrote:
>> On Thu, Feb 02, 2017 at 09:51:13AM -0500, Jintack Lim wrote:
>>> On Thu, Feb 2, 2017 at 7:31 AM, Christoffer Dall  wrote:
>>> > Hi Jintack,
>>> >
>>> > On Wed, Feb 01, 2017 at 12:43:00PM -0500, Jintack Lim wrote:
>>> >> The ARM architecture defines the EL1 physical timer and the virtual 
>>> >> timer,
>>> >> and it is reasonable for an OS to expect to be able to access both.
>>> >> However, the current KVM implementation does not provide the EL1 physical
>>> >> timer to VMs but terminates VMs on access to the timer.
>>> >>
>>> >> This patch series enables VMs to use the EL1 physical timer through
>>> >> trap-and-emulate.  The KVM host emulates each EL1 physical timer register
>>> >> access and sets up the background timer accordingly.  When the background
>>> >> timer expires, the KVM host injects EL1 physical timer interrupts to the
>>> >> VM.  Alternatively, it's also possible to allow VMs to access the EL1
>>> >> physical timer without trapping.  However, this requires somehow using 
>>> >> the
>>> >> EL2 physical timer for the Linux host while running the VM instead of the
>>> >> EL1 physical timer.  Right now I just implemented trap-and-emulate 
>>> >> because
>>> >> this was straightforward to do, and I leave it to future work to 
>>> >> determine
>>> >> if transferring the EL1 physical timer state to the EL2 timer provides 
>>> >> any
>>> >> performance benefit.
>>> >>
>>> >> This feature will be useful for any OS that wishes to access the EL1
>>> >> physical timer. Nested virtualization is one of those use cases. A nested
>>> >> hypervisor running inside a VM would think it has full access to the
>>> >> hardware and naturally tries to use the EL1 physical timer as Linux would
>>> >> do. Other nested hypervisors may try to use the EL2 physical timer as Xen
>>> >> would do, but supporting the EL2 physical timer to the VM is out of scope
>>> >> of this patch series. This patch series will make it easy to add the EL2
>>> >> timer support in the future, though.
>>> >>
>>> >> Note that Linux VMs booting in EL1 will be unaffected by this patch 
>>> >> series
>>> >> and will continue to use only the virtual timer and this patch series 
>>> >> will
>>> >> therefore not introduce any performance degredation as a result of
>>> >> trap-and-emulate.
>>> >>
>>> >> v2 => v3:
>>> >>  - Rebase on kvmarm/queue
>>> >>  - Take kvm->lock to synchronize cntvoff across all vtimers
>>> >>  - Remove unnecessary function parameters
>>> >>  - Add comments
>>> >
>>> > I just gave v3 a test run on my TC2 (32-bit platform) and my guest
>>> > quickly locks up trying to run cyclictest or when booting the machine it
>>> > stalls with RCU timeouts.
>>>
>>> Ok. It's my fault not to specify that the emulated physical timer is
>>> supported/tested on arm64.
>>> On 32-bit platform, it is supposed to show the same behavior as
>>> before, but I haven't tested.
>>> Were you using the physical timer or the virtual timer for the guest?
>>>
>>> >
>>> > Could you have a look?
>>>
>>> Sure, I'll have a look. I don't have access to my Cubietruck today,
>>> but I can work on that tomorrow.
>>>
>>
>> Don't bother, I've figured this out for you.
>
> Thanks a lot.
>
>>
>> You need the following fixup to your patch:
>
> Ok. I'll post v4 soon.
> You've already do "acked-by" for this commit. Do I need to change it
> to "signed-off-by"?
>

I guess so, technically.  I don't care deeply though.

-Christoffer
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Re: [RFC v3 00/10] Provide the EL1 physical timer to the VM

[Jintack Lim]

On Fri, Feb 3, 2017 at 7:33 AM, Christoffer Dall  wrote:
> On Thu, Feb 02, 2017 at 09:51:13AM -0500, Jintack Lim wrote:
>> On Thu, Feb 2, 2017 at 7:31 AM, Christoffer Dall  wrote:
>> > Hi Jintack,
>> >
>> > On Wed, Feb 01, 2017 at 12:43:00PM -0500, Jintack Lim wrote:
>> >> The ARM architecture defines the EL1 physical timer and the virtual timer,
>> >> and it is reasonable for an OS to expect to be able to access both.
>> >> However, the current KVM implementation does not provide the EL1 physical
>> >> timer to VMs but terminates VMs on access to the timer.
>> >>
>> >> This patch series enables VMs to use the EL1 physical timer through
>> >> trap-and-emulate.  The KVM host emulates each EL1 physical timer register
>> >> access and sets up the background timer accordingly.  When the background
>> >> timer expires, the KVM host injects EL1 physical timer interrupts to the
>> >> VM.  Alternatively, it's also possible to allow VMs to access the EL1
>> >> physical timer without trapping.  However, this requires somehow using the
>> >> EL2 physical timer for the Linux host while running the VM instead of the
>> >> EL1 physical timer.  Right now I just implemented trap-and-emulate because
>> >> this was straightforward to do, and I leave it to future work to determine
>> >> if transferring the EL1 physical timer state to the EL2 timer provides any
>> >> performance benefit.
>> >>
>> >> This feature will be useful for any OS that wishes to access the EL1
>> >> physical timer. Nested virtualization is one of those use cases. A nested
>> >> hypervisor running inside a VM would think it has full access to the
>> >> hardware and naturally tries to use the EL1 physical timer as Linux would
>> >> do. Other nested hypervisors may try to use the EL2 physical timer as Xen
>> >> would do, but supporting the EL2 physical timer to the VM is out of scope
>> >> of this patch series. This patch series will make it easy to add the EL2
>> >> timer support in the future, though.
>> >>
>> >> Note that Linux VMs booting in EL1 will be unaffected by this patch series
>> >> and will continue to use only the virtual timer and this patch series will
>> >> therefore not introduce any performance degredation as a result of
>> >> trap-and-emulate.
>> >>
>> >> v2 => v3:
>> >>  - Rebase on kvmarm/queue
>> >>  - Take kvm->lock to synchronize cntvoff across all vtimers
>> >>  - Remove unnecessary function parameters
>> >>  - Add comments
>> >
>> > I just gave v3 a test run on my TC2 (32-bit platform) and my guest
>> > quickly locks up trying to run cyclictest or when booting the machine it
>> > stalls with RCU timeouts.
>>
>> Ok. It's my fault not to specify that the emulated physical timer is
>> supported/tested on arm64.
>> On 32-bit platform, it is supposed to show the same behavior as
>> before, but I haven't tested.
>> Were you using the physical timer or the virtual timer for the guest?
>>
>> >
>> > Could you have a look?
>>
>> Sure, I'll have a look. I don't have access to my Cubietruck today,
>> but I can work on that tomorrow.
>>
>
> Don't bother, I've figured this out for you.

Thanks a lot.

>
> You need the following fixup to your patch:

Ok. I'll post v4 soon.
You've already do "acked-by" for this commit. Do I need to change it
to "signed-off-by"?

>
> diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
> index 93c811c..35d7100 100644
> --- a/virt/kvm/arm/arch_timer.c
> +++ b/virt/kvm/arm/arch_timer.c
> @@ -410,14 +410,21 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
>  }
>
>  /* Make the updates of cntvoff for all vtimer contexts atomic */
> -static void update_vtimer_cntvoff(struct kvm *kvm, u64 cntvoff)
> +static void update_vtimer_cntvoff(struct kvm_vcpu *vcpu, u64 cntvoff)
>  {
> int i;
> -   struct kvm_vcpu *vcpu;
> +   struct kvm *kvm = vcpu->kvm;
> +   struct kvm_vcpu *tmp;
>
> mutex_lock(>lock);
> -   kvm_for_each_vcpu(i, vcpu, kvm)
> -   vcpu_vtimer(vcpu)->cntvoff = cntvoff;
> +   kvm_for_each_vcpu(i, tmp, kvm)
> +   vcpu_vtimer(tmp)->cntvoff = cntvoff;
> +
> +   /*
> +* When called from the vcpu create path, the CPU being created is not
> +* included in the loop above, so we just set it here as well.
> +*/
> +   vcpu_vtimer(vcpu)->cntvoff = cntvoff;
> mutex_unlock(>lock);
>  }
>
> @@ -426,7 +433,7 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
> struct arch_timer_cpu *timer = >arch.timer_cpu;
>
> /* Synchronize cntvoff across all vtimers of a VM. */
> -   update_vtimer_cntvoff(vcpu->kvm, kvm_phys_timer_read());
> +   update_vtimer_cntvoff(vcpu, kvm_phys_timer_read());
> vcpu_ptimer(vcpu)->cntvoff = 0;
>
> INIT_WORK(>expired, kvm_timer_inject_irq_work);
> @@ -448,7 +455,7 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 
> regid, u64 value)
> vtimer->cnt_ctl = value;
> break;
> 

Re: [RFC v3 00/10] Provide the EL1 physical timer to the VM

[Christoffer Dall]

On Thu, Feb 02, 2017 at 09:51:13AM -0500, Jintack Lim wrote:
> On Thu, Feb 2, 2017 at 7:31 AM, Christoffer Dall  wrote:
> > Hi Jintack,
> >
> > On Wed, Feb 01, 2017 at 12:43:00PM -0500, Jintack Lim wrote:
> >> The ARM architecture defines the EL1 physical timer and the virtual timer,
> >> and it is reasonable for an OS to expect to be able to access both.
> >> However, the current KVM implementation does not provide the EL1 physical
> >> timer to VMs but terminates VMs on access to the timer.
> >>
> >> This patch series enables VMs to use the EL1 physical timer through
> >> trap-and-emulate.  The KVM host emulates each EL1 physical timer register
> >> access and sets up the background timer accordingly.  When the background
> >> timer expires, the KVM host injects EL1 physical timer interrupts to the
> >> VM.  Alternatively, it's also possible to allow VMs to access the EL1
> >> physical timer without trapping.  However, this requires somehow using the
> >> EL2 physical timer for the Linux host while running the VM instead of the
> >> EL1 physical timer.  Right now I just implemented trap-and-emulate because
> >> this was straightforward to do, and I leave it to future work to determine
> >> if transferring the EL1 physical timer state to the EL2 timer provides any
> >> performance benefit.
> >>
> >> This feature will be useful for any OS that wishes to access the EL1
> >> physical timer. Nested virtualization is one of those use cases. A nested
> >> hypervisor running inside a VM would think it has full access to the
> >> hardware and naturally tries to use the EL1 physical timer as Linux would
> >> do. Other nested hypervisors may try to use the EL2 physical timer as Xen
> >> would do, but supporting the EL2 physical timer to the VM is out of scope
> >> of this patch series. This patch series will make it easy to add the EL2
> >> timer support in the future, though.
> >>
> >> Note that Linux VMs booting in EL1 will be unaffected by this patch series
> >> and will continue to use only the virtual timer and this patch series will
> >> therefore not introduce any performance degredation as a result of
> >> trap-and-emulate.
> >>
> >> v2 => v3:
> >>  - Rebase on kvmarm/queue
> >>  - Take kvm->lock to synchronize cntvoff across all vtimers
> >>  - Remove unnecessary function parameters
> >>  - Add comments
> >
> > I just gave v3 a test run on my TC2 (32-bit platform) and my guest
> > quickly locks up trying to run cyclictest or when booting the machine it
> > stalls with RCU timeouts.
> 
> Ok. It's my fault not to specify that the emulated physical timer is
> supported/tested on arm64.
> On 32-bit platform, it is supposed to show the same behavior as
> before, but I haven't tested.
> Were you using the physical timer or the virtual timer for the guest?
> 
> >
> > Could you have a look?
> 
> Sure, I'll have a look. I don't have access to my Cubietruck today,
> but I can work on that tomorrow.
> 

Don't bother, I've figured this out for you.

You need the following fixup to your patch:

diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c
index 93c811c..35d7100 100644
--- a/virt/kvm/arm/arch_timer.c
+++ b/virt/kvm/arm/arch_timer.c
@@ -410,14 +410,21 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
 }
 
 /* Make the updates of cntvoff for all vtimer contexts atomic */
-static void update_vtimer_cntvoff(struct kvm *kvm, u64 cntvoff)
+static void update_vtimer_cntvoff(struct kvm_vcpu *vcpu, u64 cntvoff)
 {
int i;
-   struct kvm_vcpu *vcpu;
+   struct kvm *kvm = vcpu->kvm;
+   struct kvm_vcpu *tmp;
 
mutex_lock(>lock);
-   kvm_for_each_vcpu(i, vcpu, kvm)
-   vcpu_vtimer(vcpu)->cntvoff = cntvoff;
+   kvm_for_each_vcpu(i, tmp, kvm)
+   vcpu_vtimer(tmp)->cntvoff = cntvoff;
+
+   /*
+* When called from the vcpu create path, the CPU being created is not
+* included in the loop above, so we just set it here as well.
+*/
+   vcpu_vtimer(vcpu)->cntvoff = cntvoff;
mutex_unlock(>lock);
 }
 
@@ -426,7 +433,7 @@ void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
struct arch_timer_cpu *timer = >arch.timer_cpu;
 
/* Synchronize cntvoff across all vtimers of a VM. */
-   update_vtimer_cntvoff(vcpu->kvm, kvm_phys_timer_read());
+   update_vtimer_cntvoff(vcpu, kvm_phys_timer_read());
vcpu_ptimer(vcpu)->cntvoff = 0;
 
INIT_WORK(>expired, kvm_timer_inject_irq_work);
@@ -448,7 +455,7 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, 
u64 value)
vtimer->cnt_ctl = value;
break;
case KVM_REG_ARM_TIMER_CNT:
-   update_vtimer_cntvoff(vcpu->kvm, kvm_phys_timer_read() - value);
+   update_vtimer_cntvoff(vcpu, kvm_phys_timer_read() - value);
break;
case KVM_REG_ARM_TIMER_CVAL:
vtimer->cnt_cval = value;

This is an amuzing one.

Thanks,
-Christoffer

Re: [RFC v3 00/10] Provide the EL1 physical timer to the VM

[Christoffer Dall]

On Thu, Feb 2, 2017 at 3:51 PM, Jintack Lim  wrote:
> On Thu, Feb 2, 2017 at 7:31 AM, Christoffer Dall  wrote:
>> Hi Jintack,
>>
>> On Wed, Feb 01, 2017 at 12:43:00PM -0500, Jintack Lim wrote:
>>> The ARM architecture defines the EL1 physical timer and the virtual timer,
>>> and it is reasonable for an OS to expect to be able to access both.
>>> However, the current KVM implementation does not provide the EL1 physical
>>> timer to VMs but terminates VMs on access to the timer.
>>>
>>> This patch series enables VMs to use the EL1 physical timer through
>>> trap-and-emulate.  The KVM host emulates each EL1 physical timer register
>>> access and sets up the background timer accordingly.  When the background
>>> timer expires, the KVM host injects EL1 physical timer interrupts to the
>>> VM.  Alternatively, it's also possible to allow VMs to access the EL1
>>> physical timer without trapping.  However, this requires somehow using the
>>> EL2 physical timer for the Linux host while running the VM instead of the
>>> EL1 physical timer.  Right now I just implemented trap-and-emulate because
>>> this was straightforward to do, and I leave it to future work to determine
>>> if transferring the EL1 physical timer state to the EL2 timer provides any
>>> performance benefit.
>>>
>>> This feature will be useful for any OS that wishes to access the EL1
>>> physical timer. Nested virtualization is one of those use cases. A nested
>>> hypervisor running inside a VM would think it has full access to the
>>> hardware and naturally tries to use the EL1 physical timer as Linux would
>>> do. Other nested hypervisors may try to use the EL2 physical timer as Xen
>>> would do, but supporting the EL2 physical timer to the VM is out of scope
>>> of this patch series. This patch series will make it easy to add the EL2
>>> timer support in the future, though.
>>>
>>> Note that Linux VMs booting in EL1 will be unaffected by this patch series
>>> and will continue to use only the virtual timer and this patch series will
>>> therefore not introduce any performance degredation as a result of
>>> trap-and-emulate.
>>>
>>> v2 => v3:
>>>  - Rebase on kvmarm/queue
>>>  - Take kvm->lock to synchronize cntvoff across all vtimers
>>>  - Remove unnecessary function parameters
>>>  - Add comments
>>
>> I just gave v3 a test run on my TC2 (32-bit platform) and my guest
>> quickly locks up trying to run cyclictest or when booting the machine it
>> stalls with RCU timeouts.
>
> Ok. It's my fault not to specify that the emulated physical timer is
> supported/tested on arm64.
> On 32-bit platform, it is supposed to show the same behavior as
> before, but I haven't tested.
> Were you using the physical timer or the virtual timer for the guest?
>

I used the same guest and QEMU that I always test with so I expect it
to only use the virtual timer.

I wonder if we can somehow manage to not reset the timer properly on
the 32-bit side and end up in a form of endless interrupt loop?

>>
>> Could you have a look?
>
> Sure, I'll have a look. I don't have access to my Cubietruck today,
> but I can work on that tomorrow.
>
ok, thanks.

-Christoffer
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Re: [RFC v3 00/10] Provide the EL1 physical timer to the VM

[Jintack Lim]

On Thu, Feb 2, 2017 at 7:31 AM, Christoffer Dall  wrote:
> Hi Jintack,
>
> On Wed, Feb 01, 2017 at 12:43:00PM -0500, Jintack Lim wrote:
>> The ARM architecture defines the EL1 physical timer and the virtual timer,
>> and it is reasonable for an OS to expect to be able to access both.
>> However, the current KVM implementation does not provide the EL1 physical
>> timer to VMs but terminates VMs on access to the timer.
>>
>> This patch series enables VMs to use the EL1 physical timer through
>> trap-and-emulate.  The KVM host emulates each EL1 physical timer register
>> access and sets up the background timer accordingly.  When the background
>> timer expires, the KVM host injects EL1 physical timer interrupts to the
>> VM.  Alternatively, it's also possible to allow VMs to access the EL1
>> physical timer without trapping.  However, this requires somehow using the
>> EL2 physical timer for the Linux host while running the VM instead of the
>> EL1 physical timer.  Right now I just implemented trap-and-emulate because
>> this was straightforward to do, and I leave it to future work to determine
>> if transferring the EL1 physical timer state to the EL2 timer provides any
>> performance benefit.
>>
>> This feature will be useful for any OS that wishes to access the EL1
>> physical timer. Nested virtualization is one of those use cases. A nested
>> hypervisor running inside a VM would think it has full access to the
>> hardware and naturally tries to use the EL1 physical timer as Linux would
>> do. Other nested hypervisors may try to use the EL2 physical timer as Xen
>> would do, but supporting the EL2 physical timer to the VM is out of scope
>> of this patch series. This patch series will make it easy to add the EL2
>> timer support in the future, though.
>>
>> Note that Linux VMs booting in EL1 will be unaffected by this patch series
>> and will continue to use only the virtual timer and this patch series will
>> therefore not introduce any performance degredation as a result of
>> trap-and-emulate.
>>
>> v2 => v3:
>>  - Rebase on kvmarm/queue
>>  - Take kvm->lock to synchronize cntvoff across all vtimers
>>  - Remove unnecessary function parameters
>>  - Add comments
>
> I just gave v3 a test run on my TC2 (32-bit platform) and my guest
> quickly locks up trying to run cyclictest or when booting the machine it
> stalls with RCU timeouts.

Ok. It's my fault not to specify that the emulated physical timer is
supported/tested on arm64.
On 32-bit platform, it is supposed to show the same behavior as
before, but I haven't tested.
Were you using the physical timer or the virtual timer for the guest?

>
> Could you have a look?

Sure, I'll have a look. I don't have access to my Cubietruck today,
but I can work on that tomorrow.

>
> Thanks,
> -Christoffer
>

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Re: [RFC v3 00/10] Provide the EL1 physical timer to the VM

[Christoffer Dall]

Hi Jintack,

On Wed, Feb 01, 2017 at 12:43:00PM -0500, Jintack Lim wrote:
> The ARM architecture defines the EL1 physical timer and the virtual timer,
> and it is reasonable for an OS to expect to be able to access both.
> However, the current KVM implementation does not provide the EL1 physical
> timer to VMs but terminates VMs on access to the timer.
> 
> This patch series enables VMs to use the EL1 physical timer through
> trap-and-emulate.  The KVM host emulates each EL1 physical timer register
> access and sets up the background timer accordingly.  When the background
> timer expires, the KVM host injects EL1 physical timer interrupts to the
> VM.  Alternatively, it's also possible to allow VMs to access the EL1
> physical timer without trapping.  However, this requires somehow using the
> EL2 physical timer for the Linux host while running the VM instead of the
> EL1 physical timer.  Right now I just implemented trap-and-emulate because
> this was straightforward to do, and I leave it to future work to determine
> if transferring the EL1 physical timer state to the EL2 timer provides any
> performance benefit.
> 
> This feature will be useful for any OS that wishes to access the EL1
> physical timer. Nested virtualization is one of those use cases. A nested
> hypervisor running inside a VM would think it has full access to the
> hardware and naturally tries to use the EL1 physical timer as Linux would
> do. Other nested hypervisors may try to use the EL2 physical timer as Xen
> would do, but supporting the EL2 physical timer to the VM is out of scope
> of this patch series. This patch series will make it easy to add the EL2
> timer support in the future, though.
> 
> Note that Linux VMs booting in EL1 will be unaffected by this patch series
> and will continue to use only the virtual timer and this patch series will
> therefore not introduce any performance degredation as a result of
> trap-and-emulate.
> 
> v2 => v3:
>  - Rebase on kvmarm/queue
>  - Take kvm->lock to synchronize cntvoff across all vtimers
>  - Remove unnecessary function parameters
>  - Add comments

I just gave v3 a test run on my TC2 (32-bit platform) and my guest
quickly locks up trying to run cyclictest or when booting the machine it
stalls with RCU timeouts.

Could you have a look?

Thanks,
-Christoffer
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[RFC v3 00/10] Provide the EL1 physical timer to the VM

[Jintack Lim]

The ARM architecture defines the EL1 physical timer and the virtual timer,
and it is reasonable for an OS to expect to be able to access both.
However, the current KVM implementation does not provide the EL1 physical
timer to VMs but terminates VMs on access to the timer.

This patch series enables VMs to use the EL1 physical timer through
trap-and-emulate.  The KVM host emulates each EL1 physical timer register
access and sets up the background timer accordingly.  When the background
timer expires, the KVM host injects EL1 physical timer interrupts to the
VM.  Alternatively, it's also possible to allow VMs to access the EL1
physical timer without trapping.  However, this requires somehow using the
EL2 physical timer for the Linux host while running the VM instead of the
EL1 physical timer.  Right now I just implemented trap-and-emulate because
this was straightforward to do, and I leave it to future work to determine
if transferring the EL1 physical timer state to the EL2 timer provides any
performance benefit.

This feature will be useful for any OS that wishes to access the EL1
physical timer. Nested virtualization is one of those use cases. A nested
hypervisor running inside a VM would think it has full access to the
hardware and naturally tries to use the EL1 physical timer as Linux would
do. Other nested hypervisors may try to use the EL2 physical timer as Xen
would do, but supporting the EL2 physical timer to the VM is out of scope
of this patch series. This patch series will make it easy to add the EL2
timer support in the future, though.

Note that Linux VMs booting in EL1 will be unaffected by this patch series
and will continue to use only the virtual timer and this patch series will
therefore not introduce any performance degredation as a result of
trap-and-emulate.

v2 => v3:
 - Rebase on kvmarm/queue
 - Take kvm->lock to synchronize cntvoff across all vtimers
 - Remove unnecessary function parameters
 - Add comments

v1 => v2:
 - Rebase on kvm-arm-for-4.10-rc4
 - To make it simple, schedule the background timer for the EL1 physical timer
   emulation on every entry to the VM and cancel it on exit.
 - Change timer_context structure to have cntvoff and restore enable field back
   to arch_timer_cpu structure

Jintack Lim (10):
  KVM: arm/arm64: Abstract virtual timer context into separate structure
  KVM: arm/arm64: Move cntvoff to each timer context
  KVM: arm/arm64: Decouple kvm timer functions from virtual timer
  KVM: arm/arm64: Add the EL1 physical timer context
  KVM: arm/arm64: Initialize the emulated EL1 physical timer
  KVM: arm/arm64: Update the physical timer interrupt level
  KVM: arm/arm64: Set a background timer to the earliest timer
expiration
  KVM: arm/arm64: Set up a background timer for the physical timer
emulation
  KVM: arm64: Add the EL1 physical timer access handler
  KVM: arm/arm64: Emulate the EL1 phys timer registers

 arch/arm/include/asm/kvm_host.h   |   3 -
 arch/arm/kvm/arm.c|   4 +-
 arch/arm/kvm/reset.c  |   9 +-
 arch/arm64/include/asm/kvm_host.h |   3 -
 arch/arm64/kvm/reset.c|   9 +-
 arch/arm64/kvm/sys_regs.c |  65 +
 include/kvm/arm_arch_timer.h  |  39 
 virt/kvm/arm/arch_timer.c | 193 ++
 virt/kvm/arm/hyp/timer-sr.c   |  13 +--
 9 files changed, 242 insertions(+), 96 deletions(-)

-- 
1.9.1


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