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 <[email protected]>
Tested-by: Tomas Papan <[email protected]>
CC: [email protected]
Signed-off-by: Gleb Natapov <[email protected]>
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 5a87a58..a9fa4bc 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -5312,6 +5312,12 @@ static int handle_invalid_guest_state(struct kvm_vcpu 
*vcpu)
                        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())
--
                        Gleb.
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to