From: Sebastian Andrzej Siewior <[email protected]>

[ Upstream commit 504ce1954fba888936c9d13ccc1e3db9b8f613d5 ]

I was surprised to see that the guest reported `fxsave_leak' while the
host did not. After digging deeper I noticed that the bits are simply
masked out during enumeration.

The XSAVEERPTR feature is actually a bug fix on AMD which means the
kernel can disable a workaround.

Pass XSAVEERPTR to the guest if available on the host.

Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>
---
 arch/x86/kvm/cpuid.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index fd1b8db8bf242..59b66e343fa5a 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -479,6 +479,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 
*entry, u32 function,
 
        /* cpuid 0x80000008.ebx */
        const u32 kvm_cpuid_8000_0008_ebx_x86_features =
+               F(XSAVEERPTR) |
                F(WBNOINVD) | F(AMD_IBPB) | F(AMD_IBRS) | F(AMD_SSBD) | 
F(VIRT_SSBD) |
                F(AMD_SSB_NO) | F(AMD_STIBP) | F(AMD_STIBP_ALWAYS_ON);
 
-- 
2.20.1

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