summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorNadav Amit <namit@cs.technion.ac.il>2014-09-17 02:50:50 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2014-11-21 09:22:55 -0800
commitc75f394964bc21d0b890bd62ead90ff51b3e1e72 (patch)
treef94423db5aed3470669a96813c1db19191677832
parent2e4ce498811f1aa2e9f2e600d442ad8da0ab6534 (diff)
downloadlwn-c75f394964bc21d0b890bd62ead90ff51b3e1e72.tar.gz
lwn-c75f394964bc21d0b890bd62ead90ff51b3e1e72.zip
KVM: x86: Don't report guest userspace emulation error to userspace
commit a2b9e6c1a35afcc0973acb72e591c714e78885ff upstream. Commit fc3a9157d314 ("KVM: X86: Don't report L2 emulation failures to user-space") disabled the reporting of L2 (nested guest) emulation failures to userspace due to race-condition between a vmexit and the instruction emulator. The same rational applies also to userspace applications that are permitted by the guest OS to access MMIO area or perform PIO. This patch extends the current behavior - of injecting a #UD instead of reporting it to userspace - also for guest userspace code. Signed-off-by: Nadav Amit <namit@cs.technion.ac.il> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--arch/x86/kvm/x86.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 684f46dc87de..adfc30d9f9f4 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -4834,7 +4834,7 @@ static int handle_emulation_failure(struct kvm_vcpu *vcpu)
++vcpu->stat.insn_emulation_fail;
trace_kvm_emulate_insn_failed(vcpu);
- if (!is_guest_mode(vcpu)) {
+ if (!is_guest_mode(vcpu) && kvm_x86_ops->get_cpl(vcpu) == 0) {
vcpu->run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
vcpu->run->internal.suberror = KVM_INTERNAL_ERROR_EMULATION;
vcpu->run->internal.ndata = 0;