Allow instrumentation in the VM-Fail path of __vmcs_readl() so that the helper can be used in noinstr functions, e.g. to get the exit reason in vmx_vcpu_enter_exit() in order to handle NMI VM-Exits in the noinstr section. While allowing instrumentation isn't technically safe, KVM has much bigger problems if VMREAD fails in a noinstr section. Note, all other VMX instructions also allow instrumentation in their VM-Fail paths for similar reasons, VMREAD was simply omitted by commit 3ebccdf373c2 ("x86/kvm/vmx: Move guest enter/exit into .noinstr.text") because VMREAD wasn't used in a noinstr section at the time. Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> --- arch/x86/kvm/vmx/vmx_ops.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/kvm/vmx/vmx_ops.h b/arch/x86/kvm/vmx/vmx_ops.h index 842dc898c972..5838489e719b 100644 --- a/arch/x86/kvm/vmx/vmx_ops.h +++ b/arch/x86/kvm/vmx/vmx_ops.h @@ -100,8 +100,10 @@ static __always_inline unsigned long __vmcs_readl(unsigned long field) return value; do_fail: + instrumentation_begin(); WARN_ONCE(1, "kvm: vmread failed: field=%lx\n", field); pr_warn_ratelimited("kvm: vmread failed: field=%lx\n", field); + instrumentation_end(); return 0; do_exception: -- 2.39.0.rc1.256.g54fd8350bd-goog