[PATCH v1 6/8] kvm:cpuid Add CPUID support for CET xsaves component query.

From: Yang Weijiang
Date: Wed Dec 26 2018 - 03:13:15 EST


CET xsaves component size is queried through CPUID.(EAX=0xD, ECX=11)
and CPUID.(EAX=0xD, ECX=12).

Signed-off-by: Zhang Yi Z <yi.z.zhang@xxxxxxxxxxxxxxx>
Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx>
---
arch/x86/kvm/cpuid.c | 14 ++++++++++----
1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 7bcfa61375c0..5bac31e58955 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -565,6 +565,7 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
case 0xd: {
int idx, i;
u64 supported = kvm_supported_xcr0();
+ u64 sv_supported;

entry->eax &= supported;
entry->ebx = xstate_required_size(supported, false);
@@ -584,18 +585,23 @@ static inline int __do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function,
entry[i].eax &= kvm_cpuid_D_1_eax_x86_features;
cpuid_mask(&entry[i].eax, CPUID_D_1_EAX);
entry[i].ebx = 0;
+ sv_supported = entry[i].ecx +
+ ((u64)entry[i].edx << 32);
if (entry[i].eax & (F(XSAVES)|F(XSAVEC)))
entry[i].ebx =
xstate_required_size(supported,
true);
- } else {
+ } else if (!(entry[i].ecx & 1)) {
if (entry[i].eax == 0 || !(supported & mask))
continue;
- if (WARN_ON_ONCE(entry[i].ecx & 1))
+ entry[i].ecx = 0;
+ entry[i].edx = 0;
+ } else {
+ if (entry[i].eax == 0 || !(sv_supported & mask))
continue;
+ entry[i].ecx = 1;
+ entry[i].edx = 0;
}
- entry[i].ecx = 0;
- entry[i].edx = 0;
entry[i].flags |=
KVM_CPUID_FLAG_SIGNIFCANT_INDEX;
++*nent;
--
2.17.1