From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>
Jiri saw a hang on pause_all_vcpus called from postcopy_start,
where the cpus are all apparently stopped ('stopped' flag set)
but pause_all_vcpus is still stuck on a cond_wait on qemu_paused_cond.
We suspect this is happening if a qmp_stop is called at about the
same time as the postcopy code calls that pause_all_vcpus;
although they both should have the main lock held, Paolo spotted
the cond_wait unlocks the global lock so perhaps they both
could end up waiting at the same time?
Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
Reported-by: Jiri Denemark <jdene...@redhat.com>
Message-Id: <1453716498-27238-1-git-send-email-dgilb...@redhat.com>
Cc: qemu-sta...@nongnu.org
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
cpus.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/cpus.c b/cpus.c
index ea29584..51f5ea4 100644
--- a/cpus.c
+++ b/cpus.c
@@ -986,7 +986,7 @@ static void qemu_wait_io_event_common(CPUState *cpu)
if (cpu->stop) {
cpu->stop = false;
cpu->stopped = true;
- qemu_cond_signal(&qemu_pause_cond);
+ qemu_cond_broadcast(&qemu_pause_cond);
}
flush_queued_work(cpu);
cpu->thread_kicked = false;
@@ -1387,7 +1387,7 @@ void cpu_stop_current(void)
current_cpu->stop = false;
current_cpu->stopped = true;
cpu_exit(current_cpu);
- qemu_cond_signal(&qemu_pause_cond);
+ qemu_cond_broadcast(&qemu_pause_cond);
}
}
--
1.8.3.1
