[PATCH v1 7/8] kvm:cpuid Fix xsaves area size calculation for CPUID.(EAX=0xD,ECX=1).

Yang Weijiang
2018-12-26T08:12:54Z

According to latest Software Development Manual vol.2/3.2,
for CPUID.(EAX=0xD,ECX=1), it should report xsaves area size
containing all states enabled by XCR0|IA32_MSR_XSS.

Signed-off-by: Zhang Yi Z <yi.z.zhang@linux.intel.com>
Signed-off-by: Yang Weijiang <weijiang.yang@intel.com>
---
arch/x86/kvm/cpuid.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 5bac31e58955..55c282f71f93 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -121,7 +121,8 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu)

best = kvm_find_cpuid_entry(vcpu, 0xD, 1);
if (best && (best->eax & (F(XSAVES) | F(XSAVEC))))
- best->ebx = xstate_required_size(vcpu->arch.xcr0, true);
+ best->ebx = xstate_required_size(vcpu->arch.xcr0 |
+ best->ecx | ((u64)best->edx << 32), true);

/*
* The existing code assumes virtual address is 48-bit or 57-bit in the
--
2.17.1