diff options
Diffstat (limited to 'arch/x86/kvm/cpuid.c')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 5a5ff94fef65..0a1e3b8b964d 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -23,6 +23,26 @@ #include "mmu.h" #include "trace.h" +static u32 xstate_required_size(u64 xstate_bv) +{ + int feature_bit = 0; + u32 ret = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; + + xstate_bv &= ~XSTATE_FPSSE; + while (xstate_bv) { + if (xstate_bv & 0x1) { + u32 eax, ebx, ecx, edx; + cpuid_count(0xD, feature_bit, &eax, &ebx, &ecx, &edx); + ret = max(ret, eax + ebx); + } + + xstate_bv >>= 1; + feature_bit++; + } + + return ret; +} + void kvm_update_cpuid(struct kvm_vcpu *vcpu) { struct kvm_cpuid_entry2 *best; @@ -47,12 +67,16 @@ void kvm_update_cpuid(struct kvm_vcpu *vcpu) } best = kvm_find_cpuid_entry(vcpu, 0xD, 0); - if (!best) + if (!best) { vcpu->arch.guest_supported_xcr0 = 0; - else + vcpu->arch.guest_xstate_size = XSAVE_HDR_SIZE + XSAVE_HDR_OFFSET; + } else { 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); + } kvm_pmu_cpuid_update(vcpu); } |