| Message ID | 1450662637-5062-1-git-send-email-shuai.ruan@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
>>> On 21.12.15 at 02:50, <shuai.ruan@linux.intel.com> wrote: > Refer to SDM 13.4.3. The value return by ecx[1] with cpuid I think we've clarified before that SDM references should be by section title, not section number. > --- a/tools/libxc/xc_cpuid_x86.c > +++ b/tools/libxc/xc_cpuid_x86.c > @@ -285,6 +285,7 @@ static void intel_xc_cpuid_policy(xc_interface *xch, > #define XSAVEC (1 << 1) > #define XGETBV1 (1 << 2) > #define XSAVES (1 << 3) > +#define XSTATE_ALIGN (1 << 1) XSTATE_ALIGN64? (There might well be another, higher aligment flag in the future.) > --- a/xen/arch/x86/hvm/hvm.c > +++ b/xen/arch/x86/hvm/hvm.c > @@ -4619,7 +4619,19 @@ void hvm_cpuid(unsigned int input, unsigned int *eax, unsigned int *ebx, > for ( sub_leaf = 2; sub_leaf < 63; sub_leaf++ ) > if ( (v->arch.xcr0 | v->arch.hvm_vcpu.msr_xss) & > (1ULL << sub_leaf) ) > + { > + domain_cpuid(d, input, sub_leaf, &_eax, &_ebx, > + &_ecx, &_edx); > + /* > + * The value return by _ecx[1] indicates the > + * alignment of the state component i when the > + * compacted format of the extended region of > + * an xsave area is used. > + */ > + if (_ecx & 0x2) Needs a #define just like in libxc. Jan
diff --git a/tools/libxc/xc_cpuid_x86.c b/tools/libxc/xc_cpuid_x86.c index 8882c01..480bd83 100644 --- a/tools/libxc/xc_cpuid_x86.c +++ b/tools/libxc/xc_cpuid_x86.c @@ -285,6 +285,7 @@ static void intel_xc_cpuid_policy(xc_interface *xch, #define XSAVEC (1 << 1) #define XGETBV1 (1 << 2) #define XSAVES (1 << 3) +#define XSTATE_ALIGN (1 << 1) /* Configure extended state enumeration leaves (0x0000000D for xsave) */ static void xc_cpuid_config_xsave(xc_interface *xch, const struct cpuid_domain_info *info, @@ -333,8 +334,13 @@ static void xc_cpuid_config_xsave(xc_interface *xch, regs[0] = regs[1] = regs[2] = regs[3] = 0; break; } - /* Don't touch EAX, EBX. Also cleanup ECX and EDX */ - regs[2] = regs[3] = 0; + /* Don't touch EAX, EBX. + * ECX[1] indicates whether the state component + * needs alignment when compacted format is used. + */ + regs[2] &= XSTATE_ALIGN; + /* Clean up EDX */ + regs[3] = 0; break; } } diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c index 08cef1f..c4ac677 100644 --- a/xen/arch/x86/hvm/hvm.c +++ b/xen/arch/x86/hvm/hvm.c @@ -4619,7 +4619,19 @@ void hvm_cpuid(unsigned int input, unsigned int *eax, unsigned int *ebx, for ( sub_leaf = 2; sub_leaf < 63; sub_leaf++ ) if ( (v->arch.xcr0 | v->arch.hvm_vcpu.msr_xss) & (1ULL << sub_leaf) ) + { + domain_cpuid(d, input, sub_leaf, &_eax, &_ebx, + &_ecx, &_edx); + /* + * The value return by _ecx[1] indicates the + * alignment of the state component i when the + * compacted format of the extended region of + * an xsave area is used. + */ + if (_ecx & 0x2) + *ebx = ROUNDUP(*ebx, 64); *ebx += xstate_sizes[sub_leaf]; + } } else *ebx = *ecx = *edx = 0;
Refer to SDM 13.4.3. The value return by ecx[1] with cpuid function 0xdh and sub-fucntion i (i>1) indicates the alignment of the state component i when the compacted format of the extended region of an xsave area is used. So when hvm guest using CPUID eax=0xdh,ecx=1 to get the size of area used for compacted format, we need to take alignment into consideration. Signed-off-by: Shuai Ruan <shuai.ruan@linux.intel.com> --- tools/libxc/xc_cpuid_x86.c | 10 ++++++++-- xen/arch/x86/hvm/hvm.c | 12 ++++++++++++ 2 files changed, 20 insertions(+), 2 deletions(-)