From 74892d2468b9f0c56b915ce94848d6f7fac39740 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Thu, 5 Jun 2014 14:53:58 +0200 Subject: vl: allow other threads to do qemu_system_vmstop_request There patch protects vmstop_requested with a lock and introduces qemu_system_vmstop_request_prepare. Together with the new call to qemu_vmstop_requested in vm_start, qemu_system_vmstop_request_prepare avoids a race where the VM could remain stopped even though the iostatus of a block device has already been set (for example). qemu_system_vmstop_request_prepare however also lets the caller thread delay observation of the state change until it has itself communicated that change to the user. This delay avoids any possibility of a wrong reordering of the BLOCK_IO_ERROR event and the subsequent STOP event. Signed-off-by: Paolo Bonzini Reviewed-by: Eric Blake Signed-off-by: Stefan Hajnoczi --- cpus.c | 1 + 1 file changed, 1 insertion(+) (limited to 'cpus.c') diff --git a/cpus.c b/cpus.c index 1ec3a9edd4..06da4e7665 100644 --- a/cpus.c +++ b/cpus.c @@ -1206,6 +1206,7 @@ void cpu_stop_current(void) int vm_stop(RunState state) { if (qemu_in_vcpu_thread()) { + qemu_system_vmstop_request_prepare(); qemu_system_vmstop_request(state); /* * FIXME: should not return to device code in case -- cgit v1.2.3