If the PCIDE bit is not set in CR4, then the MSb of CR3 is a reserved
bit. If the guest tries to set it, that should cause a #GP fault. So
mask out the bit only when the PCIDE bit is set.
Signed-off-by: Junaid Shahid <junaids@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 847ce7f0a2c8..5a19d220a9c3 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -845,7 +845,10 @@ int kvm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
unsigned long old_cr3 = kvm_read_cr3(vcpu);
#ifdef CONFIG_X86_64
- cr3 &= ~CR3_PCID_INVD;
+ bool pcid_enabled = kvm_read_cr4_bits(vcpu, X86_CR4_PCIDE);
+
+ if (pcid_enabled)
+ cr3 &= ~CR3_PCID_INVD;
#endif
if (cr3 == old_cr3 && !pdptrs_changed(vcpu)) {
--
2.17.0.441.gb46fe60e1d-goog
