| Message ID | DE8DF0795D48FD4CA783C40EC829233501509B5F@SHSMSX101.ccr.corp.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Il 21/02/2014 18:39, Liu, Jinsong ha scritto: > From 00c920c96127d20d4c3bb790082700ae375c39a0 Mon Sep 17 00:00:00 2001 > From: Liu Jinsong <jinsong.liu@intel.com> > Date: Fri, 21 Feb 2014 23:47:18 +0800 > Subject: [PATCH] KVM: x86: Fix xsave cpuid exposing bug > > EBX of cpuid(0xD, 0) is dynamic per XCR0 features enable/disable. > Bit 63 of XCR0 is reserved for future expansion. > > Signed-off-by: Liu Jinsong <jinsong.liu@intel.com> > --- > arch/x86/include/asm/xsave.h | 2 ++ > arch/x86/kvm/cpuid.c | 6 +++--- > arch/x86/kvm/x86.c | 7 +++++-- > 3 files changed, 10 insertions(+), 5 deletions(-) > > diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h > index 5547389..dcd047b 100644 > --- a/arch/x86/include/asm/xsave.h > +++ b/arch/x86/include/asm/xsave.h > @@ -13,6 +13,8 @@ > #define XSTATE_BNDCSR 0x10 > > #define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE) > +/* Bit 63 of XCR0 is reserved for future expansion */ > +#define XSTATE_EXTEND_MASK (~(XSTATE_FPSSE | (1ULL << 63))) > > #define FXSAVE_SIZE 512 > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index a951ae4..b241325 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -28,7 +28,7 @@ static u32 xstate_required_size(u64 xstate_bv) > int feature_bit = 0; > u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; > > - xstate_bv &= ~XSTATE_FPSSE; > + xstate_bv &= XSTATE_EXTEND_MASK; > while (xstate_bv) { > if (xstate_bv & 0x1) { > u32 eax, ebx, ecx, edx; > @@ -74,8 +74,8 @@ void kvm_update_cpuid(struct kvm_vcpu *vcpu) > vcpu->arch.guest_supported_xcr0 = > (best->eax | ((u64)best->edx << 32)) & > host_xcr0 & KVM_SUPPORTED_XCR0; > - vcpu->arch.guest_xstate_size = > - xstate_required_size(vcpu->arch.guest_supported_xcr0); > + vcpu->arch.guest_xstate_size = best->ebx = > + xstate_required_size(vcpu->arch.xcr0); > } > > kvm_pmu_cpuid_update(vcpu); > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 39c28f0..7c52acb 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -595,13 +595,13 @@ static void kvm_put_guest_xcr0(struct kvm_vcpu *vcpu) > > int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) > { > - u64 xcr0; > + u64 xcr0 = xcr; > + u64 old_xcr0 = vcpu->arch.xcr0; > u64 valid_bits; > > /* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now */ > if (index != XCR_XFEATURE_ENABLED_MASK) > return 1; > - xcr0 = xcr; > if (!(xcr0 & XSTATE_FP)) > return 1; > if ((xcr0 & XSTATE_YMM) && !(xcr0 & XSTATE_SSE)) > @@ -618,6 +618,9 @@ int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) > > kvm_put_guest_xcr0(vcpu); > vcpu->arch.xcr0 = xcr0; > + > + if ((xcr0 ^ old_xcr0) & XSTATE_EXTEND_MASK) > + kvm_update_cpuid(vcpu); > return 0; > } > > Applied to kvm/queue, 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/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index 5547389..dcd047b 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -13,6 +13,8 @@ #define XSTATE_BNDCSR 0x10 #define XSTATE_FPSSE (XSTATE_FP | XSTATE_SSE) +/* Bit 63 of XCR0 is reserved for future expansion */ +#define XSTATE_EXTEND_MASK (~(XSTATE_FPSSE | (1ULL << 63))) #define FXSAVE_SIZE 512 diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index a951ae4..b241325 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -28,7 +28,7 @@ static u32 xstate_required_size(u64 xstate_bv) int feature_bit = 0; u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; - xstate_bv &= ~XSTATE_FPSSE; + xstate_bv &= XSTATE_EXTEND_MASK; while (xstate_bv) { if (xstate_bv & 0x1) { u32 eax, ebx, ecx, edx; @@ -74,8 +74,8 @@ void kvm_update_cpuid(struct kvm_vcpu *vcpu) vcpu->arch.guest_supported_xcr0 = (best->eax | ((u64)best->edx << 32)) & host_xcr0 & KVM_SUPPORTED_XCR0; - vcpu->arch.guest_xstate_size = - xstate_required_size(vcpu->arch.guest_supported_xcr0); + vcpu->arch.guest_xstate_size = best->ebx = + xstate_required_size(vcpu->arch.xcr0); } kvm_pmu_cpuid_update(vcpu); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 39c28f0..7c52acb 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -595,13 +595,13 @@ static void kvm_put_guest_xcr0(struct kvm_vcpu *vcpu) int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) { - u64 xcr0; + u64 xcr0 = xcr; + u64 old_xcr0 = vcpu->arch.xcr0; u64 valid_bits; /* Only support XCR_XFEATURE_ENABLED_MASK(xcr0) now */ if (index != XCR_XFEATURE_ENABLED_MASK) return 1; - xcr0 = xcr; if (!(xcr0 & XSTATE_FP)) return 1; if ((xcr0 & XSTATE_YMM) && !(xcr0 & XSTATE_SSE)) @@ -618,6 +618,9 @@ int __kvm_set_xcr(struct kvm_vcpu *vcpu, u32 index, u64 xcr) kvm_put_guest_xcr0(vcpu); vcpu->arch.xcr0 = xcr0; + + if ((xcr0 ^ old_xcr0) & XSTATE_EXTEND_MASK) + kvm_update_cpuid(vcpu); return 0; }