| Message ID | 1446615965-3898-1-git-send-email-kai.huang@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/11/2015 06:46, Kai Huang wrote: > I found PML was broken since below commit: > > commit feda805fe7c4ed9cf78158e73b1218752e3b4314 > Author: Xiao Guangrong <guangrong.xiao@linux.intel.com> > Date: Wed Sep 9 14:05:55 2015 +0800 > > KVM: VMX: unify SECONDARY_VM_EXEC_CONTROL update > > Unify the update in vmx_cpuid_update() > > Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com> > [Rewrite to use vmcs_set_secondary_exec_control. - Paolo] > Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> > > The reason is in above commit vmx_cpuid_update calls vmx_secondary_exec_control, > in which currently SECONDARY_EXEC_ENABLE_PML bit is cleared unconditionally (as > PML is enabled in creating vcpu). Therefore if vcpu_cpuid_update is called after > vcpu is created, PML will be disabled unexpectedly while log-dirty code still > thinks PML is used. > > Fix this by clearing SECONDARY_EXEC_ENABLE_PML in vmx_secondary_exec_control > only when PML is not supported or not enabled (!enable_pml). This is more > reasonable as PML is currently either always enabled or disabled. With this > explicit updating SECONDARY_EXEC_ENABLE_PML in vmx_enable{disable}_pml is not > needed so also rename vmx_enable{disable}_pml to vmx_create{destroy}_pml_buffer. > > Signed-off-by: Kai Huang <kai.huang@linux.intel.com> > > --- > > v1->v2: Fix this by following Paolo's suggestion. It's better to not to clear > SECONDARY_EXEC_ENABLE_PML in vmx_secondary_exec_control unconditionally but only > clear it when PML is not supported or enabled. > > --- > arch/x86/kvm/vmx.c | 15 +++++++-------- > 1 file changed, 7 insertions(+), 8 deletions(-) > > diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c > index 2ac11641..89f4fa2 100644 > --- a/arch/x86/kvm/vmx.c > +++ b/arch/x86/kvm/vmx.c > @@ -4718,8 +4718,9 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) > a current VMCS12 > */ > exec_control &= ~SECONDARY_EXEC_SHADOW_VMCS; > - /* PML is enabled/disabled in creating/destorying vcpu */ > - exec_control &= ~SECONDARY_EXEC_ENABLE_PML; > + > + if (!enable_pml) > + exec_control &= ~SECONDARY_EXEC_ENABLE_PML; > > /* Currently, we allow L1 guest to directly run pcommit instruction. */ > exec_control &= ~SECONDARY_EXEC_PCOMMIT; > @@ -7804,7 +7805,7 @@ static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2) > *info2 = vmcs_read32(VM_EXIT_INTR_INFO); > } > > -static int vmx_enable_pml(struct vcpu_vmx *vmx) > +static int vmx_create_pml_buffer(struct vcpu_vmx *vmx) > { > struct page *pml_pg; > > @@ -7817,12 +7818,10 @@ static int vmx_enable_pml(struct vcpu_vmx *vmx) > vmcs_write64(PML_ADDRESS, page_to_phys(vmx->pml_pg)); > vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1); > > - vmcs_set_bits(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_ENABLE_PML); > - > return 0; > } > > -static void vmx_disable_pml(struct vcpu_vmx *vmx) > +static void vmx_destroy_pml_buffer(struct vcpu_vmx *vmx) > { > ASSERT(vmx->pml_pg); > __free_page(vmx->pml_pg); > @@ -8706,7 +8705,7 @@ static void vmx_free_vcpu(struct kvm_vcpu *vcpu) > struct vcpu_vmx *vmx = to_vmx(vcpu); > > if (enable_pml) > - vmx_disable_pml(vmx); > + vmx_destroy_pml_buffer(vmx); > free_vpid(vmx->vpid); > leave_guest_mode(vcpu); > vmx_load_vmcs01(vcpu); > @@ -8790,7 +8789,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) > * for the guest, etc. > */ > if (enable_pml) { > - err = vmx_enable_pml(vmx); > + err = vmx_create_pml_buffer(vmx); > if (err) > goto free_vmcs; > } > Applied, thanks! Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 2ac11641..89f4fa2 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4718,8 +4718,9 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx) a current VMCS12 */ exec_control &= ~SECONDARY_EXEC_SHADOW_VMCS; - /* PML is enabled/disabled in creating/destorying vcpu */ - exec_control &= ~SECONDARY_EXEC_ENABLE_PML; + + if (!enable_pml) + exec_control &= ~SECONDARY_EXEC_ENABLE_PML; /* Currently, we allow L1 guest to directly run pcommit instruction. */ exec_control &= ~SECONDARY_EXEC_PCOMMIT; @@ -7804,7 +7805,7 @@ static void vmx_get_exit_info(struct kvm_vcpu *vcpu, u64 *info1, u64 *info2) *info2 = vmcs_read32(VM_EXIT_INTR_INFO); } -static int vmx_enable_pml(struct vcpu_vmx *vmx) +static int vmx_create_pml_buffer(struct vcpu_vmx *vmx) { struct page *pml_pg; @@ -7817,12 +7818,10 @@ static int vmx_enable_pml(struct vcpu_vmx *vmx) vmcs_write64(PML_ADDRESS, page_to_phys(vmx->pml_pg)); vmcs_write16(GUEST_PML_INDEX, PML_ENTITY_NUM - 1); - vmcs_set_bits(SECONDARY_VM_EXEC_CONTROL, SECONDARY_EXEC_ENABLE_PML); - return 0; } -static void vmx_disable_pml(struct vcpu_vmx *vmx) +static void vmx_destroy_pml_buffer(struct vcpu_vmx *vmx) { ASSERT(vmx->pml_pg); __free_page(vmx->pml_pg); @@ -8706,7 +8705,7 @@ static void vmx_free_vcpu(struct kvm_vcpu *vcpu) struct vcpu_vmx *vmx = to_vmx(vcpu); if (enable_pml) - vmx_disable_pml(vmx); + vmx_destroy_pml_buffer(vmx); free_vpid(vmx->vpid); leave_guest_mode(vcpu); vmx_load_vmcs01(vcpu); @@ -8790,7 +8789,7 @@ static struct kvm_vcpu *vmx_create_vcpu(struct kvm *kvm, unsigned int id) * for the guest, etc. */ if (enable_pml) { - err = vmx_enable_pml(vmx); + err = vmx_create_pml_buffer(vmx); if (err) goto free_vmcs; }