diff options
| author | Jing Liu <jing2.liu@intel.com> | 2022-01-05 13:35:25 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2022-01-14 19:44:33 +0100 |
| commit | 61f208134a871047f1d642ed3b813f4f71e30b0e (patch) | |
| tree | abc436e9f9c01f21526833cf2b6c4948ab0d5b7b /arch/x86/kvm/vmx | |
| parent | kvm: x86: Emulate IA32_XFD_ERR for guest (diff) | |
| download | linux-61f208134a871047f1d642ed3b813f4f71e30b0e.tar.xz linux-61f208134a871047f1d642ed3b813f4f71e30b0e.zip | |
kvm: x86: Disable RDMSR interception of IA32_XFD_ERR
This saves one unnecessary VM-exit in guest #NM handler, given that the
MSR is already restored with the guest value before the guest is resumed.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Jing Liu <jing2.liu@intel.com>
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20220105123532.12586-15-yang.zhong@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/vmx')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.h | 2 |
2 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 84f6904cdb6e..b8b7f5c7b3df 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -162,6 +162,7 @@ static u32 vmx_possible_passthrough_msrs[MAX_POSSIBLE_PASSTHROUGH_MSRS] = { MSR_FS_BASE, MSR_GS_BASE, MSR_KERNEL_GS_BASE, + MSR_IA32_XFD_ERR, #endif MSR_IA32_SYSENTER_CS, MSR_IA32_SYSENTER_ESP, @@ -7288,6 +7289,11 @@ static void vmx_vcpu_after_set_cpuid(struct kvm_vcpu *vcpu) } } + if (kvm_cpu_cap_has(X86_FEATURE_XFD)) + vmx_set_intercept_for_msr(vcpu, MSR_IA32_XFD_ERR, MSR_TYPE_R, + !guest_cpuid_has(vcpu, X86_FEATURE_XFD)); + + set_cr4_guest_host_mask(vmx); vmx_write_encls_bitmap(vcpu, NULL); diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index 18111368cf85..69dd2f85abdc 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -349,7 +349,7 @@ struct vcpu_vmx { struct lbr_desc lbr_desc; /* Save desired MSR intercept (read: pass-through) state */ -#define MAX_POSSIBLE_PASSTHROUGH_MSRS 13 +#define MAX_POSSIBLE_PASSTHROUGH_MSRS 14 struct { DECLARE_BITMAP(read, MAX_POSSIBLE_PASSTHROUGH_MSRS); DECLARE_BITMAP(write, MAX_POSSIBLE_PASSTHROUGH_MSRS); |