From: Sean Christopherson seanjc@google.com
[ Upstream commit 9139a7a64581c80d157027ae20e86f2f24d4292c ]
WARN if the static keys used to track if any vCPU has disabled its APIC are left elevated at module exit. Unlike the underflow case, nothing in the static key infrastructure will complain if a key is left elevated, and because an elevated key only affects performance, nothing in KVM will fail if either key is improperly incremented.
Signed-off-by: Sean Christopherson seanjc@google.com Message-Id: 20211013003554.47705-3-seanjc@google.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/kvm/lapic.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index ba5a27879f1d..18cb699b0a14 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2942,5 +2942,7 @@ int kvm_apic_accept_events(struct kvm_vcpu *vcpu) void kvm_lapic_exit(void) { static_key_deferred_flush(&apic_hw_disabled); + WARN_ON(static_branch_unlikely(&apic_hw_disabled.key)); static_key_deferred_flush(&apic_sw_disabled); + WARN_ON(static_branch_unlikely(&apic_sw_disabled.key)); }