diff mbox series

[v3,18/57] KVM: x86: Zero out PV features cache when the CPUID leaf is not present

Message ID 20241128013424.4096668-19-seanjc@google.com (mailing list archive)
State New
Headers show
Series KVM: x86: CPUID overhaul, fixes, and caching | expand

Commit Message

Sean Christopherson Nov. 28, 2024, 1:33 a.m. UTC 
Clear KVM's PV feature cache prior when processing a new guest CPUID so
that KVM doesn't keep a stale cache entry if userspace does KVM_SET_CPUID2
multiple times, once with a PV features entry, and a second time without.

Fixes: 66570e966dd9 ("kvm: x86: only provide PV features if enabled in guest's CPUID")
Cc: Oliver Upton <oliver.upton@linux.dev>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
---
 arch/x86/kvm/cpuid.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index 27919c8f438b..a94234637e09 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -251,6 +251,8 @@  void kvm_update_pv_runtime(struct kvm_vcpu *vcpu)
 {
 	struct kvm_cpuid_entry2 *best = kvm_find_kvm_cpuid_features(vcpu);
 
+	vcpu->arch.pv_cpuid.features = 0;
+
 	/*
 	 * save the feature bitmap to avoid cpuid lookup for every PV
 	 * operation