KVM Archive on lore.kernel.org
 help / color / Atom feed
* [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled
@ 2020-07-31  3:12 Wanpeng Li
  2020-07-31  3:12 ` [PATCH v3 2/3] KVM: LAPIC: Set the TDCR settable bits Wanpeng Li
                   ` (2 more replies)
  0 siblings, 3 replies; 6+ messages in thread
From: Wanpeng Li @ 2020-07-31  3:12 UTC (permalink / raw)
  To: linux-kernel, kvm
  Cc: Paolo Bonzini, Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li,
	Jim Mattson, Joerg Roedel, stable

From: Wanpeng Li <wanpengli@tencent.com>

Prevent setting the tscdeadline timer if the lapic is hw disabled.

Fixes: bce87cce88 (KVM: x86: consolidate different ways to test for in-kernel LAPIC)
Cc: <stable@vger.kernel.org>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
v1 -> v2:
 * add Fixes tag and cc stable

 arch/x86/kvm/lapic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 5bf72fc..4ce2ddd 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2195,7 +2195,7 @@ void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
 {
 	struct kvm_lapic *apic = vcpu->arch.apic;
 
-	if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
+	if (!kvm_apic_present(vcpu) || apic_lvtt_oneshot(apic) ||
 			apic_lvtt_period(apic))
 		return;
 
-- 
2.7.4


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v3 2/3] KVM: LAPIC: Set the TDCR settable bits
  2020-07-31  3:12 [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Wanpeng Li
@ 2020-07-31  3:12 ` Wanpeng Li
  2020-07-31  3:12 ` [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM Wanpeng Li
  2020-07-31  7:18 ` [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Paolo Bonzini
  2 siblings, 0 replies; 6+ messages in thread
From: Wanpeng Li @ 2020-07-31  3:12 UTC (permalink / raw)
  To: linux-kernel, kvm
  Cc: Paolo Bonzini, Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li,
	Jim Mattson, Joerg Roedel

From: Wanpeng Li <wanpengli@tencent.com>

It is a little different between Intel and AMD, Intel's bit 2
is 0 and AMD is reserved. On bare-metal, Intel will refuse to set
APIC_TDCR once bits except 0, 1, 3 are setting, however, AMD will
accept bits 0, 1, 3 and ignore other bits setting as patch does.
Before the patch, we can get back anything what we set to the
APIC_TDCR, this patch improves it.

Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
v1 -> v2:
 * update patch description

 arch/x86/kvm/lapic.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 4ce2ddd..8f7a14d 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2068,7 +2068,7 @@ int kvm_lapic_reg_write(struct kvm_lapic *apic, u32 reg, u32 val)
 	case APIC_TDCR: {
 		uint32_t old_divisor = apic->divide_count;
 
-		kvm_lapic_set_reg(apic, APIC_TDCR, val);
+		kvm_lapic_set_reg(apic, APIC_TDCR, val & 0xb);
 		update_divide_count(apic);
 		if (apic->divide_count != old_divisor &&
 				apic->lapic_timer.period) {
-- 
2.7.4


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM
  2020-07-31  3:12 [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Wanpeng Li
  2020-07-31  3:12 ` [PATCH v3 2/3] KVM: LAPIC: Set the TDCR settable bits Wanpeng Li
@ 2020-07-31  3:12 ` Wanpeng Li
  2020-07-31  7:21   ` Paolo Bonzini
  2020-07-31  7:18 ` [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Paolo Bonzini
  2 siblings, 1 reply; 6+ messages in thread
From: Wanpeng Li @ 2020-07-31  3:12 UTC (permalink / raw)
  To: linux-kernel, kvm
  Cc: Paolo Bonzini, Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li,
	Jim Mattson, Joerg Roedel

From: Wanpeng Li <wanpengli@tencent.com>

'Commit 8566ac8b8e7c ("KVM: SVM: Implement pause loop exit logic in SVM")' 
drops disable pause loop exit/pause filtering capability completely, I 
guess it is a merge fault by Radim since disable vmexits capabilities and 
pause loop exit for SVM patchsets are merged at the same time. This patch 
reintroduces the disable pause loop exit/pause filtering capability support.

Reported-by: Haiwei Li <lihaiwei@tencent.com>
Tested-by: Haiwei Li <lihaiwei@tencent.com>
Fixes: 8566ac8b (KVM: SVM: Implement pause loop exit logic in SVM)
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
---
v2 -> v3:
 * simplify the condition in init_vmcb() 

 arch/x86/kvm/svm/svm.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index c0da4dd..bf77f90 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1090,7 +1090,7 @@ static void init_vmcb(struct vcpu_svm *svm)
 	svm->nested.vmcb = 0;
 	svm->vcpu.arch.hflags = 0;
 
-	if (pause_filter_count) {
+	if (!kvm_pause_in_guest(svm->vcpu.kvm)) {
 		control->pause_filter_count = pause_filter_count;
 		if (pause_filter_thresh)
 			control->pause_filter_thresh = pause_filter_thresh;
@@ -2693,7 +2693,7 @@ static int pause_interception(struct vcpu_svm *svm)
 	struct kvm_vcpu *vcpu = &svm->vcpu;
 	bool in_kernel = (svm_get_cpl(vcpu) == 0);
 
-	if (pause_filter_thresh)
+	if (!kvm_pause_in_guest(vcpu->kvm))
 		grow_ple_window(vcpu);
 
 	kvm_vcpu_on_spin(vcpu, in_kernel);
@@ -3780,7 +3780,7 @@ static void svm_handle_exit_irqoff(struct kvm_vcpu *vcpu)
 
 static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
 {
-	if (pause_filter_thresh)
+	if (!kvm_pause_in_guest(vcpu->kvm))
 		shrink_ple_window(vcpu);
 }
 
@@ -3958,6 +3958,9 @@ static void svm_vm_destroy(struct kvm *kvm)
 
 static int svm_vm_init(struct kvm *kvm)
 {
+	if (!pause_filter_count || !pause_filter_thresh)
+		kvm->arch.pause_in_guest = true;
+
 	if (avic) {
 		int ret = avic_vm_init(kvm);
 		if (ret)
-- 
2.7.4


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled
  2020-07-31  3:12 [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Wanpeng Li
  2020-07-31  3:12 ` [PATCH v3 2/3] KVM: LAPIC: Set the TDCR settable bits Wanpeng Li
  2020-07-31  3:12 ` [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM Wanpeng Li
@ 2020-07-31  7:18 ` Paolo Bonzini
  2 siblings, 0 replies; 6+ messages in thread
From: Paolo Bonzini @ 2020-07-31  7:18 UTC (permalink / raw)
  To: Wanpeng Li, linux-kernel, kvm
  Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
	Joerg Roedel, stable

On 31/07/20 05:12, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@tencent.com>
> 
> Prevent setting the tscdeadline timer if the lapic is hw disabled.
> 
> Fixes: bce87cce88 (KVM: x86: consolidate different ways to test for in-kernel LAPIC)
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> ---
> v1 -> v2:
>  * add Fixes tag and cc stable
> 
>  arch/x86/kvm/lapic.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 5bf72fc..4ce2ddd 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -2195,7 +2195,7 @@ void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data)
>  {
>  	struct kvm_lapic *apic = vcpu->arch.apic;
>  
> -	if (!lapic_in_kernel(vcpu) || apic_lvtt_oneshot(apic) ||
> +	if (!kvm_apic_present(vcpu) || apic_lvtt_oneshot(apic) ||
>  			apic_lvtt_period(apic))
>  		return;
>  
> 

Testcase please.

Paolo


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM
  2020-07-31  3:12 ` [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM Wanpeng Li
@ 2020-07-31  7:21   ` Paolo Bonzini
  2020-07-31  9:44     ` Wanpeng Li
  0 siblings, 1 reply; 6+ messages in thread
From: Paolo Bonzini @ 2020-07-31  7:21 UTC (permalink / raw)
  To: Wanpeng Li, linux-kernel, kvm
  Cc: Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li, Jim Mattson,
	Joerg Roedel

On 31/07/20 05:12, Wanpeng Li wrote:
> From: Wanpeng Li <wanpengli@tencent.com>
> 
> 'Commit 8566ac8b8e7c ("KVM: SVM: Implement pause loop exit logic in SVM")' 
> drops disable pause loop exit/pause filtering capability completely, I 
> guess it is a merge fault by Radim since disable vmexits capabilities and 
> pause loop exit for SVM patchsets are merged at the same time. This patch 
> reintroduces the disable pause loop exit/pause filtering capability support.
> 
> Reported-by: Haiwei Li <lihaiwei@tencent.com>
> Tested-by: Haiwei Li <lihaiwei@tencent.com>
> Fixes: 8566ac8b (KVM: SVM: Implement pause loop exit logic in SVM)
> Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> ---
> v2 -> v3:
>  * simplify the condition in init_vmcb() 
> 
>  arch/x86/kvm/svm/svm.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> index c0da4dd..bf77f90 100644
> --- a/arch/x86/kvm/svm/svm.c
> +++ b/arch/x86/kvm/svm/svm.c
> @@ -1090,7 +1090,7 @@ static void init_vmcb(struct vcpu_svm *svm)
>  	svm->nested.vmcb = 0;
>  	svm->vcpu.arch.hflags = 0;
>  
> -	if (pause_filter_count) {
> +	if (!kvm_pause_in_guest(svm->vcpu.kvm)) {
>  		control->pause_filter_count = pause_filter_count;
>  		if (pause_filter_thresh)
>  			control->pause_filter_thresh = pause_filter_thresh;
> @@ -2693,7 +2693,7 @@ static int pause_interception(struct vcpu_svm *svm)
>  	struct kvm_vcpu *vcpu = &svm->vcpu;
>  	bool in_kernel = (svm_get_cpl(vcpu) == 0);
>  
> -	if (pause_filter_thresh)
> +	if (!kvm_pause_in_guest(vcpu->kvm))
>  		grow_ple_window(vcpu);
>  
>  	kvm_vcpu_on_spin(vcpu, in_kernel);
> @@ -3780,7 +3780,7 @@ static void svm_handle_exit_irqoff(struct kvm_vcpu *vcpu)
>  
>  static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
>  {
> -	if (pause_filter_thresh)
> +	if (!kvm_pause_in_guest(vcpu->kvm))
>  		shrink_ple_window(vcpu);
>  }
>  
> @@ -3958,6 +3958,9 @@ static void svm_vm_destroy(struct kvm *kvm)
>  
>  static int svm_vm_init(struct kvm *kvm)
>  {
> +	if (!pause_filter_count || !pause_filter_thresh)
> +		kvm->arch.pause_in_guest = true;
> +
>  	if (avic) {
>  		int ret = avic_vm_init(kvm);
>  		if (ret)
> 

Queued all three, thanks.  Please do send a testcase for patch 1
however, I only queued it in order to have it in 5.8.

Paolo


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM
  2020-07-31  7:21   ` Paolo Bonzini
@ 2020-07-31  9:44     ` Wanpeng Li
  0 siblings, 0 replies; 6+ messages in thread
From: Wanpeng Li @ 2020-07-31  9:44 UTC (permalink / raw)
  To: Paolo Bonzini
  Cc: LKML, kvm, Sean Christopherson, Vitaly Kuznetsov, Wanpeng Li,
	Jim Mattson, Joerg Roedel

On Fri, 31 Jul 2020 at 15:21, Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> On 31/07/20 05:12, Wanpeng Li wrote:
> > From: Wanpeng Li <wanpengli@tencent.com>
> >
> > 'Commit 8566ac8b8e7c ("KVM: SVM: Implement pause loop exit logic in SVM")'
> > drops disable pause loop exit/pause filtering capability completely, I
> > guess it is a merge fault by Radim since disable vmexits capabilities and
> > pause loop exit for SVM patchsets are merged at the same time. This patch
> > reintroduces the disable pause loop exit/pause filtering capability support.
> >
> > Reported-by: Haiwei Li <lihaiwei@tencent.com>
> > Tested-by: Haiwei Li <lihaiwei@tencent.com>
> > Fixes: 8566ac8b (KVM: SVM: Implement pause loop exit logic in SVM)
> > Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
> > ---
> > v2 -> v3:
> >  * simplify the condition in init_vmcb()
> >
> >  arch/x86/kvm/svm/svm.c | 9 ++++++---
> >  1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> > index c0da4dd..bf77f90 100644
> > --- a/arch/x86/kvm/svm/svm.c
> > +++ b/arch/x86/kvm/svm/svm.c
> > @@ -1090,7 +1090,7 @@ static void init_vmcb(struct vcpu_svm *svm)
> >       svm->nested.vmcb = 0;
> >       svm->vcpu.arch.hflags = 0;
> >
> > -     if (pause_filter_count) {
> > +     if (!kvm_pause_in_guest(svm->vcpu.kvm)) {
> >               control->pause_filter_count = pause_filter_count;
> >               if (pause_filter_thresh)
> >                       control->pause_filter_thresh = pause_filter_thresh;
> > @@ -2693,7 +2693,7 @@ static int pause_interception(struct vcpu_svm *svm)
> >       struct kvm_vcpu *vcpu = &svm->vcpu;
> >       bool in_kernel = (svm_get_cpl(vcpu) == 0);
> >
> > -     if (pause_filter_thresh)
> > +     if (!kvm_pause_in_guest(vcpu->kvm))
> >               grow_ple_window(vcpu);
> >
> >       kvm_vcpu_on_spin(vcpu, in_kernel);
> > @@ -3780,7 +3780,7 @@ static void svm_handle_exit_irqoff(struct kvm_vcpu *vcpu)
> >
> >  static void svm_sched_in(struct kvm_vcpu *vcpu, int cpu)
> >  {
> > -     if (pause_filter_thresh)
> > +     if (!kvm_pause_in_guest(vcpu->kvm))
> >               shrink_ple_window(vcpu);
> >  }
> >
> > @@ -3958,6 +3958,9 @@ static void svm_vm_destroy(struct kvm *kvm)
> >
> >  static int svm_vm_init(struct kvm *kvm)
> >  {
> > +     if (!pause_filter_count || !pause_filter_thresh)
> > +             kvm->arch.pause_in_guest = true;
> > +
> >       if (avic) {
> >               int ret = avic_vm_init(kvm);
> >               if (ret)
> >
>
> Queued all three, thanks.  Please do send a testcase for patch 1
> however, I only queued it in order to have it in 5.8.

Thanks, will do in the next week, today is too busy. :)

    Wanpeng

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, back to index

Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-07-31  3:12 [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Wanpeng Li
2020-07-31  3:12 ` [PATCH v3 2/3] KVM: LAPIC: Set the TDCR settable bits Wanpeng Li
2020-07-31  3:12 ` [PATCH v3 3/3] KVM: SVM: Fix disable pause loop exit/pause filtering capability on SVM Wanpeng Li
2020-07-31  7:21   ` Paolo Bonzini
2020-07-31  9:44     ` Wanpeng Li
2020-07-31  7:18 ` [PATCH v3 1/3] KVM: LAPIC: Prevent setting the tscdeadline timer if the lapic is hw disabled Paolo Bonzini

KVM Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/kvm/0 kvm/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 kvm kvm/ https://lore.kernel.org/kvm \
		kvm@vger.kernel.org
	public-inbox-index kvm

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.kvm


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git