From e171327c07f33c79dab763e08feb7b0ad24dfe71 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Wed, 8 May 2013 18:38:44 +0300 Subject: [PATCH] KVM: VMX: fix halt emulation while emulating invalid guest sate commit 8d76c49e9ffeee839bc0b7a3278a23f99101263e upstream. The invalid guest state emulation loop does not check halt_request which causes 100% cpu loop while guest is in halt and in invalid state, but more serious issue is that this leaves halt_request set, so random instruction emulated by vm86 #GP exit can be interpreted as halt which causes guest hang. Fix both problems by handling halt_request in emulation loop. Reported-by: Tomas Papan Tested-by: Tomas Papan Reviewed-by: Paolo Bonzini Signed-off-by: Gleb Natapov Signed-off-by: Greg Kroah-Hartman --- arch/x86/kvm/vmx.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 2ad060acc44..be1d830ca98 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -3836,6 +3836,12 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu) if (err != EMULATE_DONE) return 0; + if (vcpu->arch.halt_request) { + vcpu->arch.halt_request = 0; + ret = kvm_emulate_halt(vcpu); + goto out; + } + if (signal_pending(current)) goto out; if (need_resched()) -- 2.34.1