Prevent abortion on multiple VCPU kicks

If we call qemu_cpu_kick more than once before the target was able to
process the signal, pthread_kill will fail, and qemu will abort. Prevent
this by avoiding the redundant signal.

This logic can be found in qemu-kvm as well.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/cpus.c b/cpus.c
index 4c9928e2ce..ab6e40e93d 100644
--- a/cpus.c
+++ b/cpus.c
@@ -481,6 +481,7 @@ static void qemu_wait_io_event_common(CPUState *env)
         qemu_cond_signal(&qemu_pause_cond);
     }
     flush_queued_work(env);
+    env->thread_kicked = false;
 }
 
 static void qemu_tcg_wait_io_event(void)
@@ -648,7 +649,10 @@ void qemu_cpu_kick(void *_env)
 {
     CPUState *env = _env;
     qemu_cond_broadcast(env->halt_cond);
-    qemu_thread_signal(env->thread, SIG_IPI);
+    if (!env->thread_kicked) {
+        qemu_thread_signal(env->thread, SIG_IPI);
+        env->thread_kicked = true;
+    }
 }
 
 int qemu_cpu_self(void *_env)