| Message ID | 20230511040857.6094-9-weijiang.yang@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Enable CET Virtualization | expand |
On Thu, May 11, 2023 at 12:08:44AM -0400, Yang Weijiang wrote: >Initialize kvm_caps.supported_xss with host XSS msr value AND XSS mask. >KVM_SUPPORTED_XSS holds all potential supported feature bits, >the result >represents all KVM supported feature bits which is used for swapping guest >and host FPU contents. do you mean kvm_caps.supported_xss by "the result"? I don't see how fpu_swap_kvm_fpstate() uses kvm_caps.supported_xss. > >Signed-off-by: Yang Weijiang <weijiang.yang@intel.com> >--- > arch/x86/kvm/vmx/vmx.c | 1 - > arch/x86/kvm/x86.c | 6 +++++- > 2 files changed, 5 insertions(+), 2 deletions(-) > >diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c >index 44fb619803b8..c872a5aafa50 100644 >--- a/arch/x86/kvm/vmx/vmx.c >+++ b/arch/x86/kvm/vmx/vmx.c >@@ -7806,7 +7806,6 @@ static __init void vmx_set_cpu_caps(void) > kvm_cpu_cap_set(X86_FEATURE_UMIP); > > /* CPUID 0xD.1 */ >- kvm_caps.supported_xss = 0; AMD has the same statement. Do you need to remove that one? > if (!cpu_has_vmx_xsaves()) > kvm_cpu_cap_clear(X86_FEATURE_XSAVES); > >diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >index ab3360a10933..d2975ca96ac5 100644 >--- a/arch/x86/kvm/x86.c >+++ b/arch/x86/kvm/x86.c >@@ -223,6 +223,8 @@ static struct kvm_user_return_msrs __percpu *user_return_msrs; > | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ > | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE) > >+#define KVM_SUPPORTED_XSS 0 >+ > u64 __read_mostly host_efer; > EXPORT_SYMBOL_GPL(host_efer); > >@@ -9472,8 +9474,10 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) > > rdmsrl_safe(MSR_EFER, &host_efer); > >- if (boot_cpu_has(X86_FEATURE_XSAVES)) >+ if (boot_cpu_has(X86_FEATURE_XSAVES)) { > rdmsrl(MSR_IA32_XSS, host_xss); >+ kvm_caps.supported_xss = host_xss & KVM_SUPPORTED_XSS; >+ } > > kvm_init_pmu_capability(ops->pmu_ops); > >-- >2.27.0 >
On 6/6/2023 4:38 PM, Chao Gao wrote: > On Thu, May 11, 2023 at 12:08:44AM -0400, Yang Weijiang wrote: >> Initialize kvm_caps.supported_xss with host XSS msr value AND XSS mask. >> KVM_SUPPORTED_XSS holds all potential supported feature bits, >> the result >> represents all KVM supported feature bits which is used for swapping guest >> and host FPU contents. > do you mean kvm_caps.supported_xss by "the result"? I don't see how > fpu_swap_kvm_fpstate() uses kvm_caps.supported_xss. The wording is not accurate, what I meant is : the resulting bits are supported by fpu_swap_kvm_fpstate(). I will change the commit logs in next version, thanks! > >> Signed-off-by: Yang Weijiang <weijiang.yang@intel.com> >> --- >> arch/x86/kvm/vmx/vmx.c | 1 - >> arch/x86/kvm/x86.c | 6 +++++- >> 2 files changed, 5 insertions(+), 2 deletions(-) >> >> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c >> index 44fb619803b8..c872a5aafa50 100644 >> --- a/arch/x86/kvm/vmx/vmx.c >> +++ b/arch/x86/kvm/vmx/vmx.c >> @@ -7806,7 +7806,6 @@ static __init void vmx_set_cpu_caps(void) >> kvm_cpu_cap_set(X86_FEATURE_UMIP); >> >> /* CPUID 0xD.1 */ >> - kvm_caps.supported_xss = 0; > AMD has the same statement. Do you need to remove that one? Since it appears in svm.c, so I assume Allen(AMD) will change it in his following up patch series. [...]
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 44fb619803b8..c872a5aafa50 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7806,7 +7806,6 @@ static __init void vmx_set_cpu_caps(void) kvm_cpu_cap_set(X86_FEATURE_UMIP); /* CPUID 0xD.1 */ - kvm_caps.supported_xss = 0; if (!cpu_has_vmx_xsaves()) kvm_cpu_cap_clear(X86_FEATURE_XSAVES); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index ab3360a10933..d2975ca96ac5 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -223,6 +223,8 @@ static struct kvm_user_return_msrs __percpu *user_return_msrs; | XFEATURE_MASK_BNDCSR | XFEATURE_MASK_AVX512 \ | XFEATURE_MASK_PKRU | XFEATURE_MASK_XTILE) +#define KVM_SUPPORTED_XSS 0 + u64 __read_mostly host_efer; EXPORT_SYMBOL_GPL(host_efer); @@ -9472,8 +9474,10 @@ static int __kvm_x86_vendor_init(struct kvm_x86_init_ops *ops) rdmsrl_safe(MSR_EFER, &host_efer); - if (boot_cpu_has(X86_FEATURE_XSAVES)) + if (boot_cpu_has(X86_FEATURE_XSAVES)) { rdmsrl(MSR_IA32_XSS, host_xss); + kvm_caps.supported_xss = host_xss & KVM_SUPPORTED_XSS; + } kvm_init_pmu_capability(ops->pmu_ops);
Initialize kvm_caps.supported_xss with host XSS msr value AND XSS mask. KVM_SUPPORTED_XSS holds all potential supported feature bits, the result represents all KVM supported feature bits which is used for swapping guest and host FPU contents. Signed-off-by: Yang Weijiang <weijiang.yang@intel.com> --- arch/x86/kvm/vmx/vmx.c | 1 - arch/x86/kvm/x86.c | 6 +++++- 2 files changed, 5 insertions(+), 2 deletions(-)