aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorJan Kiszka <jan.kiszka@siemens.com>2014-10-27 14:05:10 +0000
committerPeter Maydell <peter.maydell@linaro.org>2014-10-27 14:09:27 +0000
commit817ef04db2cfa2df04daffd6917f4ea7605f6403 (patch)
tree2c4d84c6cdda963f4aa929766311487b8649cee3
parentff0d48768bd51717b05e77014221b66543953731 (diff)
downloadqemu-817ef04db2cfa2df04daffd6917f4ea7605f6403.zip
qemu-817ef04db2cfa2df04daffd6917f4ea7605f6403.tar.gz
qemu-817ef04db2cfa2df04daffd6917f4ea7605f6403.tar.bz2
Make qemu_shutdown_requested signal-safe
qemu_shutdown_requested may be interrupted by qemu_system_killed. If the latter sets shutdown_requested after qemu_shutdown_requested has read it but before it was cleared, the shutdown event is lost. Fix this by using atomic_xchg. This provides a different fix for the problem which commit 15124e142 attempts to deal with. That commit breaks use of ^C to drop into gdb, and so this approach is better (and 15124e142 can be reverted). Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com> Reviewed-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> [PMM: commit message tweak] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
-rw-r--r--vl.c4
1 files changed, 1 insertions, 3 deletions
diff --git a/vl.c b/vl.c
index 2f81384..f6b3546 100644
--- a/vl.c
+++ b/vl.c
@@ -1609,9 +1609,7 @@ int qemu_reset_requested_get(void)
static int qemu_shutdown_requested(void)
{
- int r = shutdown_requested;
- shutdown_requested = 0;
- return r;
+ return atomic_xchg(&shutdown_requested, 0);
}
static void qemu_kill_report(void)