From: Lai Jiangshan <[email protected]>
Add FSGSBASE to the set of possible guest-owned CR4 bits, i.e. let the
guest own it on VMX. KVM never queries the guest's CR4.FSGSBASE value,
thus there is no reason to force VM-Exit on FSGSBASE being toggled.
Note, because FSGSBASE is conditionally available, this is dependent on
recent changes to intercept reserved CR4 bits and to update the CR4
guest/host mask in response to guest CPUID changes.
Cc: Paolo Bonzini <[email protected]>
Signed-off-by: Lai Jiangshan <[email protected]>
[sean: added justification in changelog]
Signed-off-by: Sean Christopherson <[email protected]>
---
arch/x86/kvm/kvm_cache_regs.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index ca0781b41df9..a889563ad02d 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -7,7 +7,7 @@
#define KVM_POSSIBLE_CR0_GUEST_BITS X86_CR0_TS
#define KVM_POSSIBLE_CR4_GUEST_BITS \
(X86_CR4_PVI | X86_CR4_DE | X86_CR4_PCE | X86_CR4_OSFXSR \
- | X86_CR4_OSXMMEXCPT | X86_CR4_PGE | X86_CR4_TSD)
+ | X86_CR4_OSXMMEXCPT | X86_CR4_PGE | X86_CR4_TSD | X86_CR4_FSGSBASE)
#define BUILD_KVM_GPR_ACCESSORS(lname, uname) \
static __always_inline unsigned long kvm_##lname##_read(struct kvm_vcpu *vcpu)\
--
2.28.0