[PATCH 5.10 464/663] KVM: SVM: Intercept INVPCID when its disabled to inject #UD

From: Greg Kroah-Hartman
Date: Mon Mar 01 2021 - 23:15:12 EST


From: Sean Christopherson <seanjc@xxxxxxxxxx>

[ Upstream commit 0a8ed2eaac102c746d8d114f2787f06cb3e55dfb ]

Intercept INVPCID if it's disabled in the guest, even when using NPT,
as KVM needs to inject #UD in this case.

Fixes: 4407a797e941 ("KVM: SVM: Enable INVPCID feature on AMD")
Cc: Babu Moger <babu.moger@xxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Message-Id: <20210212003411.1102677-2-seanjc@xxxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
arch/x86/kvm/svm/svm.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index f4ae3871e412a..76ab1ee0784ae 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1092,12 +1092,12 @@ static u64 svm_write_l1_tsc_offset(struct kvm_vcpu *vcpu, u64 offset)
static void svm_check_invpcid(struct vcpu_svm *svm)
{
/*
- * Intercept INVPCID instruction only if shadow page table is
- * enabled. Interception is not required with nested page table
- * enabled.
+ * Intercept INVPCID if shadow paging is enabled to sync/free shadow
+ * roots, or if INVPCID is disabled in the guest to inject #UD.
*/
if (kvm_cpu_cap_has(X86_FEATURE_INVPCID)) {
- if (!npt_enabled)
+ if (!npt_enabled ||
+ !guest_cpuid_has(&svm->vcpu, X86_FEATURE_INVPCID))
svm_set_intercept(svm, INTERCEPT_INVPCID);
else
svm_clr_intercept(svm, INTERCEPT_INVPCID);
--
2.27.0