public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
* [PATCH] kvm: fix hyperv tsc page clear wrong address
       [not found] <53A2BB7B.8070507@gmail.com>
@ 2014-06-19 10:31 ` =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
  2014-06-19 11:17   ` =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
  0 siblings, 1 reply; 3+ messages in thread
From: =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?= @ 2014-06-19 10:31 UTC (permalink / raw)
  To: gleb, pbonzini, tglx, mingo, hpa; +Cc: x86, kvm, linux-kernel

[-- Attachment #1: Type: text/plain, Size: 1197 bytes --]

>From 6010e24da995d4161cb879e98fda989e3cdb41c4 Mon Sep 17 00:00:00 2001
From: Xiaoming Gao <newtongao@tencent.com>
Date: Thu, 19 Jun 2014 17:46:05 +0800
Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address

tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits
before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead
guest to get wrong clocksource.

windows guest will get strong impact, QueryPerformanceCounter will always return 0
,all things in windows rely on clock source will in serious chaos.

Signed-off-by: Xiaoming Gao <newtongao@tencnet.com>
---
 arch/x86/kvm/x86.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f32a025..ed716cf 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1898,6 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 		if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE))
 			break;
 		gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
+		data &= ~((1 << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT) - 1);
 		if (kvm_write_guest(kvm, data,
 			&tsc_ref, sizeof(tsc_ref)))
 			return 1;
-- 
1.7.1




[-- Attachment #2: 0001-kvm-fix-hyperv-tsc-page-clear-wrong-address.patch --]
[-- Type: text/plain, Size: 1196 bytes --]

>From 6010e24da995d4161cb879e98fda989e3cdb41c4 Mon Sep 17 00:00:00 2001
From: Xiaoming Gao <newtongao@tencent.com>
Date: Thu, 19 Jun 2014 17:46:05 +0800
Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address

tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits
before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead
guest to get wrong clocksource.

windows guest will get strong impact, QueryPerformanceCounter will always return 0
,all things in windows rely on clock source, will in serious chaos.

Signed-off-by: Xiaoming Gao <newtongao@tencnet.com>
---
 arch/x86/kvm/x86.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f32a025..ed716cf 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1898,6 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 		if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE))
 			break;
 		gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
+		data &= ~((1 << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT) - 1);
 		if (kvm_write_guest(kvm, data,
 			&tsc_ref, sizeof(tsc_ref)))
 			return 1;
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] kvm: fix hyperv tsc page clear wrong address
  2014-06-19 10:31 ` [PATCH] kvm: fix hyperv tsc page clear wrong address =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
@ 2014-06-19 11:17   ` =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
  2014-06-19 11:22     ` Paolo Bonzini
  0 siblings, 1 reply; 3+ messages in thread
From: =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?= @ 2014-06-19 11:17 UTC (permalink / raw)
  To: gleb, pbonzini, tglx, mingo, hpa; +Cc: x86, kvm, linux-kernel

[-- Attachment #1: Type: text/plain, Size: 1261 bytes --]

This is more concisely

>From 6ddeb18347f9dda0fe37702e0d067a4129a89b54 Mon Sep 17 00:00:00 2001
From: Xiaoming Gao <newtongao@tencent.com>
Date: Thu, 19 Jun 2014 19:14:57 +0800
Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address

tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits
before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead
guest to get wrong clocksource.

windows guest will get strong impact, QueryPerformanceCounter will always return 0
,all things in windows rely on clock source, will in serious chaos.

Signed-off-by: Xiaoming Gao <newtongao@tencnet.com>
---
 arch/x86/kvm/x86.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f32a025..f644933 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1898,7 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 		if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE))
 			break;
 		gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
-		if (kvm_write_guest(kvm, data,
+		if (kvm_write_guest(kvm, gfn << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT,
 			&tsc_ref, sizeof(tsc_ref)))
 			return 1;
 		mark_page_dirty(kvm, gfn);
-- 
1.7.1


[-- Attachment #2: 0001-kvm-fix-hyperv-tsc-page-clear-wrong-address.patch --]
[-- Type: text/plain, Size: 1237 bytes --]

>From 6ddeb18347f9dda0fe37702e0d067a4129a89b54 Mon Sep 17 00:00:00 2001
From: Xiaoming Gao <newtongao@tencent.com>
Date: Thu, 19 Jun 2014 19:14:57 +0800
Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address

tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits
before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead
guest to get wrong clocksource.

windows guest will get strong impact, QueryPerformanceCounter will always return 0
,all things in windows rely on clock source, will in serious chaos.

Signed-off-by: Xiaoming Gao <newtongao@tencnet.com>
---
 arch/x86/kvm/x86.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f32a025..f644933 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1898,7 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
 		if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE))
 			break;
 		gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
-		if (kvm_write_guest(kvm, data,
+		if (kvm_write_guest(kvm, gfn << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT,
 			&tsc_ref, sizeof(tsc_ref)))
 			return 1;
 		mark_page_dirty(kvm, gfn);
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] kvm: fix hyperv tsc page clear wrong address
  2014-06-19 11:17   ` =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
@ 2014-06-19 11:22     ` Paolo Bonzini
  0 siblings, 0 replies; 3+ messages in thread
From: Paolo Bonzini @ 2014-06-19 11:22 UTC (permalink / raw)
  To: =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=, gleb, tglx,
	mingo, hpa
  Cc: x86, kvm, linux-kernel

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset=gb18030; format=flowed, Size: 1445 bytes --]

Il 19/06/2014 13:17, "newtongao(¸ßСÃ÷)" ha scritto:
> This is more concisely
>
> From 6ddeb18347f9dda0fe37702e0d067a4129a89b54 Mon Sep 17 00:00:00 2001
> From: Xiaoming Gao <newtongao@tencent.com>
> Date: Thu, 19 Jun 2014 19:14:57 +0800
> Subject: [PATCH] kvm: fix hyperv tsc page clear wrong address
>
> tsc page addr need clear the low HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT bits
> before kvm_write_guest write the zero tsc_ref structure to guest, or it will lead
> guest to get wrong clocksource.
>
> windows guest will get strong impact, QueryPerformanceCounter will always return 0
> ,all things in windows rely on clock source, will in serious chaos.

Right, this can happen if Windows passes a non-zero page to KVM.

Thanks,

Paolo

> Signed-off-by: Xiaoming Gao <newtongao@tencnet.com>
> ---
>  arch/x86/kvm/x86.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index f32a025..f644933 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -1898,7 +1898,7 @@ static int set_msr_hyperv_pw(struct kvm_vcpu *vcpu, u32 msr, u64 data)
>  		if (!(data & HV_X64_MSR_TSC_REFERENCE_ENABLE))
>  			break;
>  		gfn = data >> HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT;
> -		if (kvm_write_guest(kvm, data,
> +		if (kvm_write_guest(kvm, gfn << HV_X64_MSR_TSC_REFERENCE_ADDRESS_SHIFT,
>  			&tsc_ref, sizeof(tsc_ref)))
>  			return 1;
>  		mark_page_dirty(kvm, gfn);
>


^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2014-06-19 11:22 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
     [not found] <53A2BB7B.8070507@gmail.com>
2014-06-19 10:31 ` [PATCH] kvm: fix hyperv tsc page clear wrong address =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
2014-06-19 11:17   ` =?gb18030?Q?=22newtongao=28=B8=DF=D0=A1=C3=F7=29=22?=
2014-06-19 11:22     ` Paolo Bonzini

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox