diff options
Diffstat (limited to 'arch/x86/kvm/vmx/vmx.c')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 17 |
1 files changed, 13 insertions, 4 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index cc60b1fc3ee7..eb69fef57485 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -6860,11 +6860,20 @@ static int vmx_create_vcpu(struct kvm_vcpu *vcpu) switch (index) { case MSR_IA32_TSX_CTRL: /* - * No need to pass TSX_CTRL_CPUID_CLEAR through, so - * let's avoid changing CPUID bits under the host - * kernel's feet. + * TSX_CTRL_CPUID_CLEAR is handled in the CPUID + * interception. Keep the host value unchanged to avoid + * changing CPUID bits under the host kernel's feet. + * + * hle=0, rtm=0, tsx_ctrl=1 can be found with some + * combinations of new kernel and old userspace. If + * those guests run on a tsx=off host, do allow guests + * to use TSX_CTRL, but do not change the value on the + * host so that TSX remains always disabled. */ - vmx->guest_uret_msrs[j].mask = ~(u64)TSX_CTRL_CPUID_CLEAR; + if (boot_cpu_has(X86_FEATURE_RTM)) + vmx->guest_uret_msrs[j].mask = ~(u64)TSX_CTRL_CPUID_CLEAR; + else + vmx->guest_uret_msrs[j].mask = 0; break; default: vmx->guest_uret_msrs[j].mask = -1ull; |