* [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT
@ 2017-11-15 11:43 Liran Alon
2017-11-15 13:47 ` Paolo Bonzini
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Liran Alon @ 2017-11-15 11:43 UTC (permalink / raw)
To: pbonzini, rkrcmar, kvm; +Cc: idan.brown, Liran Alon, Konrad Rzeszutek Wilk
This MSR returns the number of #SMIs that occurred on CPU since
boot.
It was seen to be used frequently by ESXi guest.
Patch adds a new vcpu-arch specific var called smi_count to
save the number of #SMIs which occurred on CPU since boot.
It is exposed as a read-only MSR to guest (causing #GP
on wrmsr) in RDMSR/WRMSR emulation code.
MSR_SMI_COUNT is also added to emulated_msrs[] to make sure
user-space can save/restore it for migration purposes.
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
---
Notes:
To make vmsave/vload work for MSR_SMI_COUNT (for migration purposes),
a patch for QEMU is also required.
We have written such patch and verified that it works.
It will be submitted seperately to the QEMU mailing list.
arch/x86/include/asm/kvm_host.h | 1 +
arch/x86/kvm/x86.c | 11 +++++++++++
2 files changed, 12 insertions(+)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index c73e493adf07..089856eeac5d 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -504,6 +504,7 @@ struct kvm_vcpu_arch {
int mp_state;
u64 ia32_misc_enable_msr;
u64 smbase;
+ u64 smi_count;
bool tpr_access_reporting;
u64 ia32_xss;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 21c00594f230..dedf5539f924 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1036,6 +1036,7 @@ bool kvm_rdpmc(struct kvm_vcpu *vcpu)
MSR_IA32_MCG_CTL,
MSR_IA32_MCG_EXT_CTL,
MSR_IA32_SMBASE,
+ MSR_SMI_COUNT,
MSR_PLATFORM_INFO,
MSR_MISC_FEATURES_ENABLES,
};
@@ -2217,6 +2218,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return 1;
vcpu->arch.smbase = data;
break;
+ case MSR_SMI_COUNT:
+ if (!msr_info->host_initiated)
+ return 1;
+ vcpu->arch.smi_count = data;
+ break;
case MSR_KVM_WALL_CLOCK_NEW:
case MSR_KVM_WALL_CLOCK:
vcpu->kvm->arch.wall_clock = data;
@@ -2491,6 +2497,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return 1;
msr_info->data = vcpu->arch.smbase;
break;
+ case MSR_SMI_COUNT:
+ msr_info->data = vcpu->arch.smi_count;
+ break;
case MSR_IA32_PERF_STATUS:
/* TSC increment by tick */
msr_info->data = 1000ULL;
@@ -6437,6 +6446,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
kvm_x86_ops->queue_exception(vcpu);
} else if (vcpu->arch.smi_pending && !is_smm(vcpu)) {
vcpu->arch.smi_pending = false;
+ ++vcpu->arch.smi_count;
enter_smm(vcpu);
} else if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
--vcpu->arch.nmi_pending;
@@ -7781,6 +7791,7 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
vcpu->arch.hflags = 0;
vcpu->arch.smi_pending = 0;
+ vcpu->arch.smi_count = 0;
atomic_set(&vcpu->arch.nmi_queued, 0);
vcpu->arch.nmi_pending = 0;
vcpu->arch.nmi_injected = false;
--
1.9.1
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT
2017-11-15 11:43 [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT Liran Alon
@ 2017-11-15 13:47 ` Paolo Bonzini
2017-12-04 9:27 ` David Hildenbrand
2017-12-05 21:09 ` Radim Krčmář
2 siblings, 0 replies; 6+ messages in thread
From: Paolo Bonzini @ 2017-11-15 13:47 UTC (permalink / raw)
To: Liran Alon, rkrcmar, kvm; +Cc: idan.brown, Konrad Rzeszutek Wilk
On 15/11/2017 12:43, Liran Alon wrote:
> This MSR returns the number of #SMIs that occurred on CPU since
> boot.
>
> It was seen to be used frequently by ESXi guest.
>
> Patch adds a new vcpu-arch specific var called smi_count to
> save the number of #SMIs which occurred on CPU since boot.
> It is exposed as a read-only MSR to guest (causing #GP
> on wrmsr) in RDMSR/WRMSR emulation code.
> MSR_SMI_COUNT is also added to emulated_msrs[] to make sure
> user-space can save/restore it for migration purposes.
>
> Signed-off-by: Liran Alon <liran.alon@oracle.com>
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
> Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
>
> Notes:
> To make vmsave/vload work for MSR_SMI_COUNT (for migration purposes),
> a patch for QEMU is also required.
> We have written such patch and verified that it works.
> It will be submitted seperately to the QEMU mailing list.
>
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/kvm/x86.c | 11 +++++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index c73e493adf07..089856eeac5d 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -504,6 +504,7 @@ struct kvm_vcpu_arch {
> int mp_state;
> u64 ia32_misc_enable_msr;
> u64 smbase;
> + u64 smi_count;
> bool tpr_access_reporting;
> u64 ia32_xss;
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 21c00594f230..dedf5539f924 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1036,6 +1036,7 @@ bool kvm_rdpmc(struct kvm_vcpu *vcpu)
> MSR_IA32_MCG_CTL,
> MSR_IA32_MCG_EXT_CTL,
> MSR_IA32_SMBASE,
> + MSR_SMI_COUNT,
> MSR_PLATFORM_INFO,
> MSR_MISC_FEATURES_ENABLES,
> };
> @@ -2217,6 +2218,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> return 1;
> vcpu->arch.smbase = data;
> break;
> + case MSR_SMI_COUNT:
> + if (!msr_info->host_initiated)
> + return 1;
> + vcpu->arch.smi_count = data;
> + break;
> case MSR_KVM_WALL_CLOCK_NEW:
> case MSR_KVM_WALL_CLOCK:
> vcpu->kvm->arch.wall_clock = data;
> @@ -2491,6 +2497,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> return 1;
> msr_info->data = vcpu->arch.smbase;
> break;
> + case MSR_SMI_COUNT:
> + msr_info->data = vcpu->arch.smi_count;
> + break;
> case MSR_IA32_PERF_STATUS:
> /* TSC increment by tick */
> msr_info->data = 1000ULL;
> @@ -6437,6 +6446,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
> kvm_x86_ops->queue_exception(vcpu);
> } else if (vcpu->arch.smi_pending && !is_smm(vcpu)) {
> vcpu->arch.smi_pending = false;
> + ++vcpu->arch.smi_count;
> enter_smm(vcpu);
> } else if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
> --vcpu->arch.nmi_pending;
> @@ -7781,6 +7791,7 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> vcpu->arch.hflags = 0;
>
> vcpu->arch.smi_pending = 0;
> + vcpu->arch.smi_count = 0;
> atomic_set(&vcpu->arch.nmi_queued, 0);
> vcpu->arch.nmi_pending = 0;
> vcpu->arch.nmi_injected = false;
>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT
2017-11-15 11:43 [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT Liran Alon
2017-11-15 13:47 ` Paolo Bonzini
@ 2017-12-04 9:27 ` David Hildenbrand
2017-12-04 9:31 ` Paolo Bonzini
2017-12-05 21:09 ` Radim Krčmář
2 siblings, 1 reply; 6+ messages in thread
From: David Hildenbrand @ 2017-12-04 9:27 UTC (permalink / raw)
To: Liran Alon, pbonzini, rkrcmar, kvm; +Cc: idan.brown, Konrad Rzeszutek Wilk
On 15.11.2017 12:43, Liran Alon wrote:
> This MSR returns the number of #SMIs that occurred on CPU since
> boot.
>
> It was seen to be used frequently by ESXi guest.
>
> Patch adds a new vcpu-arch specific var called smi_count to
> save the number of #SMIs which occurred on CPU since boot.
> It is exposed as a read-only MSR to guest (causing #GP
> on wrmsr) in RDMSR/WRMSR emulation code.
> MSR_SMI_COUNT is also added to emulated_msrs[] to make sure
> user-space can save/restore it for migration purposes.
>
> Signed-off-by: Liran Alon <liran.alon@oracle.com>
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
> Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
>
> Notes:
> To make vmsave/vload work for MSR_SMI_COUNT (for migration purposes),
> a patch for QEMU is also required.
> We have written such patch and verified that it works.
> It will be submitted seperately to the QEMU mailing list.
>
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/kvm/x86.c | 11 +++++++++++
> 2 files changed, 12 insertions(+)
>
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index c73e493adf07..089856eeac5d 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -504,6 +504,7 @@ struct kvm_vcpu_arch {
> int mp_state;
> u64 ia32_misc_enable_msr;
> u64 smbase;
> + u64 smi_count;
> bool tpr_access_reporting;
> u64 ia32_xss;
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 21c00594f230..dedf5539f924 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1036,6 +1036,7 @@ bool kvm_rdpmc(struct kvm_vcpu *vcpu)
> MSR_IA32_MCG_CTL,
> MSR_IA32_MCG_EXT_CTL,
> MSR_IA32_SMBASE,
> + MSR_SMI_COUNT,
> MSR_PLATFORM_INFO,
> MSR_MISC_FEATURES_ENABLES,
> };
> @@ -2217,6 +2218,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> return 1;
> vcpu->arch.smbase = data;
> break;
> + case MSR_SMI_COUNT:
> + if (!msr_info->host_initiated)
> + return 1;
> + vcpu->arch.smi_count = data;
> + break;
> case MSR_KVM_WALL_CLOCK_NEW:
> case MSR_KVM_WALL_CLOCK:
> vcpu->kvm->arch.wall_clock = data;
> @@ -2491,6 +2497,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> return 1;
> msr_info->data = vcpu->arch.smbase;
> break;
> + case MSR_SMI_COUNT:
> + msr_info->data = vcpu->arch.smi_count;
> + break;
> case MSR_IA32_PERF_STATUS:
> /* TSC increment by tick */
> msr_info->data = 1000ULL;
> @@ -6437,6 +6446,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
> kvm_x86_ops->queue_exception(vcpu);
> } else if (vcpu->arch.smi_pending && !is_smm(vcpu)) {
> vcpu->arch.smi_pending = false;
> + ++vcpu->arch.smi_count;
> enter_smm(vcpu);
> } else if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
> --vcpu->arch.nmi_pending;
> @@ -7781,6 +7791,7 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
> vcpu->arch.hflags = 0;
>
> vcpu->arch.smi_pending = 0;
> + vcpu->arch.smi_count = 0;
> atomic_set(&vcpu->arch.nmi_queued, 0);
> vcpu->arch.nmi_pending = 0;
> vcpu->arch.nmi_injected = false;
>
Reviewed-by: David Hildenbrand <david@redhat.com>
(only wondering if we have to make availability depend on e.g. a
KVM_CAP, so a guest will not silently start using it, although migration
with old QEMUs is broken)
--
Thanks,
David / dhildenb
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT
2017-12-04 9:27 ` David Hildenbrand
@ 2017-12-04 9:31 ` Paolo Bonzini
2017-12-04 9:32 ` David Hildenbrand
0 siblings, 1 reply; 6+ messages in thread
From: Paolo Bonzini @ 2017-12-04 9:31 UTC (permalink / raw)
To: David Hildenbrand, Liran Alon, rkrcmar, kvm
Cc: idan.brown, Konrad Rzeszutek Wilk
On 04/12/2017 10:27, David Hildenbrand wrote:
> On 15.11.2017 12:43, Liran Alon wrote:
>> This MSR returns the number of #SMIs that occurred on CPU since
>> boot.
>>
>> It was seen to be used frequently by ESXi guest.
>>
>> Patch adds a new vcpu-arch specific var called smi_count to
>> save the number of #SMIs which occurred on CPU since boot.
>> It is exposed as a read-only MSR to guest (causing #GP
>> on wrmsr) in RDMSR/WRMSR emulation code.
>> MSR_SMI_COUNT is also added to emulated_msrs[] to make sure
>> user-space can save/restore it for migration purposes.
>>
>> Signed-off-by: Liran Alon <liran.alon@oracle.com>
>> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
>> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
>> Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
>> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
>> ---
>>
>> Notes:
>> To make vmsave/vload work for MSR_SMI_COUNT (for migration purposes),
>> a patch for QEMU is also required.
>> We have written such patch and verified that it works.
>> It will be submitted seperately to the QEMU mailing list.
>>
>> arch/x86/include/asm/kvm_host.h | 1 +
>> arch/x86/kvm/x86.c | 11 +++++++++++
>> 2 files changed, 12 insertions(+)
>>
>> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
>> index c73e493adf07..089856eeac5d 100644
>> --- a/arch/x86/include/asm/kvm_host.h
>> +++ b/arch/x86/include/asm/kvm_host.h
>> @@ -504,6 +504,7 @@ struct kvm_vcpu_arch {
>> int mp_state;
>> u64 ia32_misc_enable_msr;
>> u64 smbase;
>> + u64 smi_count;
>> bool tpr_access_reporting;
>> u64 ia32_xss;
>>
>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>> index 21c00594f230..dedf5539f924 100644
>> --- a/arch/x86/kvm/x86.c
>> +++ b/arch/x86/kvm/x86.c
>> @@ -1036,6 +1036,7 @@ bool kvm_rdpmc(struct kvm_vcpu *vcpu)
>> MSR_IA32_MCG_CTL,
>> MSR_IA32_MCG_EXT_CTL,
>> MSR_IA32_SMBASE,
>> + MSR_SMI_COUNT,
>> MSR_PLATFORM_INFO,
>> MSR_MISC_FEATURES_ENABLES,
>> };
>> @@ -2217,6 +2218,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
>> return 1;
>> vcpu->arch.smbase = data;
>> break;
>> + case MSR_SMI_COUNT:
>> + if (!msr_info->host_initiated)
>> + return 1;
>> + vcpu->arch.smi_count = data;
>> + break;
>> case MSR_KVM_WALL_CLOCK_NEW:
>> case MSR_KVM_WALL_CLOCK:
>> vcpu->kvm->arch.wall_clock = data;
>> @@ -2491,6 +2497,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
>> return 1;
>> msr_info->data = vcpu->arch.smbase;
>> break;
>> + case MSR_SMI_COUNT:
>> + msr_info->data = vcpu->arch.smi_count;
>> + break;
>> case MSR_IA32_PERF_STATUS:
>> /* TSC increment by tick */
>> msr_info->data = 1000ULL;
>> @@ -6437,6 +6446,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
>> kvm_x86_ops->queue_exception(vcpu);
>> } else if (vcpu->arch.smi_pending && !is_smm(vcpu)) {
>> vcpu->arch.smi_pending = false;
>> + ++vcpu->arch.smi_count;
>> enter_smm(vcpu);
>> } else if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
>> --vcpu->arch.nmi_pending;
>> @@ -7781,6 +7791,7 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
>> vcpu->arch.hflags = 0;
>>
>> vcpu->arch.smi_pending = 0;
>> + vcpu->arch.smi_count = 0;
>> atomic_set(&vcpu->arch.nmi_queued, 0);
>> vcpu->arch.nmi_pending = 0;
>> vcpu->arch.nmi_injected = false;
>>
>
> Reviewed-by: David Hildenbrand <david@redhat.com>
>
> (only wondering if we have to make availability depend on e.g. a
> KVM_CAP, so a guest will not silently start using it, although migration
> with old QEMUs is broken)
No need for a capability, old QEMU will just reset to 0 on migration.
Paolo
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT
2017-12-04 9:31 ` Paolo Bonzini
@ 2017-12-04 9:32 ` David Hildenbrand
0 siblings, 0 replies; 6+ messages in thread
From: David Hildenbrand @ 2017-12-04 9:32 UTC (permalink / raw)
To: Paolo Bonzini, Liran Alon, rkrcmar, kvm; +Cc: idan.brown, Konrad Rzeszutek Wilk
On 04.12.2017 10:31, Paolo Bonzini wrote:
> On 04/12/2017 10:27, David Hildenbrand wrote:
>> On 15.11.2017 12:43, Liran Alon wrote:
>>> This MSR returns the number of #SMIs that occurred on CPU since
>>> boot.
>>>
>>> It was seen to be used frequently by ESXi guest.
>>>
>>> Patch adds a new vcpu-arch specific var called smi_count to
>>> save the number of #SMIs which occurred on CPU since boot.
>>> It is exposed as a read-only MSR to guest (causing #GP
>>> on wrmsr) in RDMSR/WRMSR emulation code.
>>> MSR_SMI_COUNT is also added to emulated_msrs[] to make sure
>>> user-space can save/restore it for migration purposes.
>>>
>>> Signed-off-by: Liran Alon <liran.alon@oracle.com>
>>> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
>>> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
>>> Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
>>> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
>>> ---
>>>
>>> Notes:
>>> To make vmsave/vload work for MSR_SMI_COUNT (for migration purposes),
>>> a patch for QEMU is also required.
>>> We have written such patch and verified that it works.
>>> It will be submitted seperately to the QEMU mailing list.
>>>
>>> arch/x86/include/asm/kvm_host.h | 1 +
>>> arch/x86/kvm/x86.c | 11 +++++++++++
>>> 2 files changed, 12 insertions(+)
>>>
>>> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
>>> index c73e493adf07..089856eeac5d 100644
>>> --- a/arch/x86/include/asm/kvm_host.h
>>> +++ b/arch/x86/include/asm/kvm_host.h
>>> @@ -504,6 +504,7 @@ struct kvm_vcpu_arch {
>>> int mp_state;
>>> u64 ia32_misc_enable_msr;
>>> u64 smbase;
>>> + u64 smi_count;
>>> bool tpr_access_reporting;
>>> u64 ia32_xss;
>>>
>>> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
>>> index 21c00594f230..dedf5539f924 100644
>>> --- a/arch/x86/kvm/x86.c
>>> +++ b/arch/x86/kvm/x86.c
>>> @@ -1036,6 +1036,7 @@ bool kvm_rdpmc(struct kvm_vcpu *vcpu)
>>> MSR_IA32_MCG_CTL,
>>> MSR_IA32_MCG_EXT_CTL,
>>> MSR_IA32_SMBASE,
>>> + MSR_SMI_COUNT,
>>> MSR_PLATFORM_INFO,
>>> MSR_MISC_FEATURES_ENABLES,
>>> };
>>> @@ -2217,6 +2218,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
>>> return 1;
>>> vcpu->arch.smbase = data;
>>> break;
>>> + case MSR_SMI_COUNT:
>>> + if (!msr_info->host_initiated)
>>> + return 1;
>>> + vcpu->arch.smi_count = data;
>>> + break;
>>> case MSR_KVM_WALL_CLOCK_NEW:
>>> case MSR_KVM_WALL_CLOCK:
>>> vcpu->kvm->arch.wall_clock = data;
>>> @@ -2491,6 +2497,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
>>> return 1;
>>> msr_info->data = vcpu->arch.smbase;
>>> break;
>>> + case MSR_SMI_COUNT:
>>> + msr_info->data = vcpu->arch.smi_count;
>>> + break;
>>> case MSR_IA32_PERF_STATUS:
>>> /* TSC increment by tick */
>>> msr_info->data = 1000ULL;
>>> @@ -6437,6 +6446,7 @@ static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
>>> kvm_x86_ops->queue_exception(vcpu);
>>> } else if (vcpu->arch.smi_pending && !is_smm(vcpu)) {
>>> vcpu->arch.smi_pending = false;
>>> + ++vcpu->arch.smi_count;
>>> enter_smm(vcpu);
>>> } else if (vcpu->arch.nmi_pending && kvm_x86_ops->nmi_allowed(vcpu)) {
>>> --vcpu->arch.nmi_pending;
>>> @@ -7781,6 +7791,7 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
>>> vcpu->arch.hflags = 0;
>>>
>>> vcpu->arch.smi_pending = 0;
>>> + vcpu->arch.smi_count = 0;
>>> atomic_set(&vcpu->arch.nmi_queued, 0);
>>> vcpu->arch.nmi_pending = 0;
>>> vcpu->arch.nmi_injected = false;
>>>
>>
>> Reviewed-by: David Hildenbrand <david@redhat.com>
>>
>> (only wondering if we have to make availability depend on e.g. a
>> KVM_CAP, so a guest will not silently start using it, although migration
>> with old QEMUs is broken)
>
> No need for a capability, old QEMU will just reset to 0 on migration.
>
If that is acceptable (i.e. smi_count might jump back) , fine with me.
> Paolo
>
--
Thanks,
David / dhildenb
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT
2017-11-15 11:43 [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT Liran Alon
2017-11-15 13:47 ` Paolo Bonzini
2017-12-04 9:27 ` David Hildenbrand
@ 2017-12-05 21:09 ` Radim Krčmář
2 siblings, 0 replies; 6+ messages in thread
From: Radim Krčmář @ 2017-12-05 21:09 UTC (permalink / raw)
To: Liran Alon; +Cc: pbonzini, kvm, idan.brown, Konrad Rzeszutek Wilk
2017-11-15 13:43+0200, Liran Alon:
> This MSR returns the number of #SMIs that occurred on CPU since
> boot.
>
> It was seen to be used frequently by ESXi guest.
>
> Patch adds a new vcpu-arch specific var called smi_count to
> save the number of #SMIs which occurred on CPU since boot.
> It is exposed as a read-only MSR to guest (causing #GP
> on wrmsr) in RDMSR/WRMSR emulation code.
> MSR_SMI_COUNT is also added to emulated_msrs[] to make sure
> user-space can save/restore it for migration purposes.
>
> Signed-off-by: Liran Alon <liran.alon@oracle.com>
> Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
> Reviewed-by: Bhavesh Davda <bhavesh.davda@oracle.com>
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
> ---
Queued, thanks.
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-12-05 21:09 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-11-15 11:43 [PATCH] KVM: x86: Add emulation of MSR_SMI_COUNT Liran Alon
2017-11-15 13:47 ` Paolo Bonzini
2017-12-04 9:27 ` David Hildenbrand
2017-12-04 9:31 ` Paolo Bonzini
2017-12-04 9:32 ` David Hildenbrand
2017-12-05 21:09 ` Radim Krčmář
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