>From b060be65e466291c91963e58c4880ec614d0b294 Mon Sep 17 00:00:00 2001 From: Liu Jinsong <jinsong.liu@xxxxxxxxx> Date: Fri, 29 Nov 2013 01:27:53 +0800 Subject: [PATCH 2/4] 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@xxxxxxxxx> --- arch/x86/include/asm/xsave.h | 2 ++ arch/x86/kvm/cpuid.c | 4 ++-- 2 files changed, 4 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index d3e3ea5..6120e74 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 | (1 << 63))) #define FXSAVE_SIZE 512 diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index c697625..a8ce117 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; @@ -74,7 +74,7 @@ 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 = + vcpu->arch.guest_xstate_size = best->ebx = xstate_required_size(vcpu->arch.guest_supported_xcr0); } -- 1.7.1
Attachment:
0002-KVM-X86-Fix-xsave-cpuid-exposing-bug.patch
Description: 0002-KVM-X86-Fix-xsave-cpuid-exposing-bug.patch