> From: Zhong, Yang <yang.zh...@intel.com> > Sent: Friday, January 7, 2022 5:32 PM > > From: Jing Liu <jing2....@intel.com> > > Intel introduces XFD faulting mechanism for extended > XSAVE features to dynamically enable the features in > runtime. If CPUID (EAX=0Dh, ECX=n, n>1).ECX[2] is set > as 1, it indicates support for XFD faulting of this > state component. > > Signed-off-by: Jing Liu <jing2....@intel.com> > Signed-off-by: Yang Zhong <yang.zh...@intel.com> > --- > target/i386/cpu.h | 2 +- > target/i386/cpu.c | 2 +- > target/i386/kvm/kvm-cpu.c | 1 + > 3 files changed, 3 insertions(+), 2 deletions(-) > > diff --git a/target/i386/cpu.h b/target/i386/cpu.h > index 79023fe723..22f7ff40a6 100644 > --- a/target/i386/cpu.h > +++ b/target/i386/cpu.h > @@ -1375,7 +1375,7 @@ > QEMU_BUILD_BUG_ON(sizeof(XSaveXTILE_DATA) != 0x2000); > typedef struct ExtSaveArea { > uint32_t feature, bits; > uint32_t offset, size; > - uint32_t need_align; > + uint32_t need_align, support_xfd;
why each flag be a 32-bit field? also it's more natural to have them in separate lines, though I'm not sure why existing fields are put this way (possibly due to short names?). > } ExtSaveArea; > > #define XSAVE_STATE_AREA_COUNT (XSTATE_XTILE_DATA_BIT + 1) > diff --git a/target/i386/cpu.c b/target/i386/cpu.c > index dd2c919c33..1adc3f0f99 100644 > --- a/target/i386/cpu.c > +++ b/target/i386/cpu.c > @@ -5495,7 +5495,7 @@ void cpu_x86_cpuid(CPUX86State *env, uint32_t > index, uint32_t count, > const ExtSaveArea *esa = &x86_ext_save_areas[count]; > *eax = esa->size; > *ebx = esa->offset; > - *ecx = esa->need_align << 1; > + *ecx = (esa->need_align << 1) | (esa->support_xfd << 2); > } > } > break; > diff --git a/target/i386/kvm/kvm-cpu.c b/target/i386/kvm/kvm-cpu.c > index 6c4c1c6f9d..3b3c203f11 100644 > --- a/target/i386/kvm/kvm-cpu.c > +++ b/target/i386/kvm/kvm-cpu.c > @@ -108,6 +108,7 @@ static void kvm_cpu_xsave_init(void) > > uint32_t ecx = kvm_arch_get_supported_cpuid(s, 0xd, i, R_ECX); > esa->need_align = ecx & (1u << 1) ? 1 : 0; > + esa->support_xfd = ecx & (1u << 2) ? 1 : 0; > } > } > }