| Message ID | 20200523161455.3940-2-mlevitsk@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Fix issue with not starting nesting guests on my system | expand |
On Sat, May 23, 2020 at 07:14:54PM +0300, Maxim Levitsky wrote: > Even though we might not allow the guest to use > WAITPKG's new instructions, we should tell KVM > that the feature is supported by the host CPU. > > Note that vmx_waitpkg_supported checks that WAITPKG > _can_ be set in secondary execution controls as specified > by VMX capability MSR, rather that we actually enable it for a guest. These line wraps are quite weird and inconsistent. > > Fixes: e69e72faa3a0 KVM: x86: Add support for user wait instructions Checkpatch doesn't complain, but the preferred Fixes format is Fixes: e69e72faa3a07 ("KVM: x86: Add support for user wait instructions") e.g. git show -s --pretty='tformat:%h ("%s")' For the code itself: Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> > Suggested-by: Paolo Bonzini <pbonzini@redhat.com> > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> > --- > arch/x86/kvm/vmx/vmx.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index 55712dd86bafa..fca493d4517c5 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -7298,6 +7298,9 @@ static __init void vmx_set_cpu_caps(void) > /* CPUID 0x80000001 */ > if (!cpu_has_vmx_rdtscp()) > kvm_cpu_cap_clear(X86_FEATURE_RDTSCP); > + > + if (vmx_waitpkg_supported()) > + kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG); > } > > static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu) > -- > 2.26.2 >
On Tue, 2020-05-26 at 18:20 -0700, Sean Christopherson wrote: > On Sat, May 23, 2020 at 07:14:54PM +0300, Maxim Levitsky wrote: > > Even though we might not allow the guest to use > > WAITPKG's new instructions, we should tell KVM > > that the feature is supported by the host CPU. > > > > Note that vmx_waitpkg_supported checks that WAITPKG > > _can_ be set in secondary execution controls as specified > > by VMX capability MSR, rather that we actually enable it for a > > guest. > > These line wraps are quite weird and inconsistent. Known issue for me, I usually don't have line wrapping enabled, and I wrap the lines a bit earlier that 72 character limit. I'll re-formatted the commit message to be on 72 line format and I will try now to pay much more attention to that. > > > Fixes: e69e72faa3a0 KVM: x86: Add support for user wait > > instructions > > Checkpatch doesn't complain, but the preferred Fixes format is > > Fixes: e69e72faa3a07 ("KVM: x86: Add support for user wait > instructions") > > e.g. > > git show -s --pretty='tformat:%h ("%s")' Got it, and added to git aliases :-) > > For the code itself: > > Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Thank you! > > > Suggested-by: Paolo Bonzini <pbonzini@redhat.com> > > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> > > --- > > arch/x86/kvm/vmx/vmx.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > > index 55712dd86bafa..fca493d4517c5 100644 > > --- a/arch/x86/kvm/vmx/vmx.c > > +++ b/arch/x86/kvm/vmx/vmx.c > > @@ -7298,6 +7298,9 @@ static __init void vmx_set_cpu_caps(void) > > /* CPUID 0x80000001 */ > > if (!cpu_has_vmx_rdtscp()) > > kvm_cpu_cap_clear(X86_FEATURE_RDTSCP); > > + > > + if (vmx_waitpkg_supported()) > > + kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG); > > } > > > > static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu) > > -- > > 2.26.2 > >
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 55712dd86bafa..fca493d4517c5 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7298,6 +7298,9 @@ static __init void vmx_set_cpu_caps(void) /* CPUID 0x80000001 */ if (!cpu_has_vmx_rdtscp()) kvm_cpu_cap_clear(X86_FEATURE_RDTSCP); + + if (vmx_waitpkg_supported()) + kvm_cpu_cap_check_and_set(X86_FEATURE_WAITPKG); } static void vmx_request_immediate_exit(struct kvm_vcpu *vcpu)
Even though we might not allow the guest to use WAITPKG's new instructions, we should tell KVM that the feature is supported by the host CPU. Note that vmx_waitpkg_supported checks that WAITPKG _can_ be set in secondary execution controls as specified by VMX capability MSR, rather that we actually enable it for a guest. Fixes: e69e72faa3a0 KVM: x86: Add support for user wait instructions Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com> --- arch/x86/kvm/vmx/vmx.c | 3 +++ 1 file changed, 3 insertions(+)