BUG/MINOR: mworker: disable SIGPROF on re-exec
If haproxy is built with profiling enabled with -pg, it is possible to
see the master quit during a reload while it's re-executing itself with
error code 155 (signal 27) saying "Profile timer expired)". This happens
if the SIGPROF signal is delivered during the execve() call while the
handler was already unregistered. The issue itself is not directly inside
haproxy but it's easy to address. This patch disables this signal before
calling execvp() during a master reload. A simple test for this consists
in running this little script with haproxy started in master-worker mode :
$ while usleep 50000; do killall -USR2 haproxy; done
This fix should be backported to all versions using the master-worker
model.
(cherry picked from commit e0d86e2c1caaaa2141118e3309d479de5f67e855)
Signed-off-by: Willy Tarreau <w@1wt.eu>
diff --git a/src/haproxy.c b/src/haproxy.c
index f6f00fc..c93b0d1 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -695,6 +695,7 @@
}
ha_warning("Reexecuting Master process\n");
+ signal(SIGPROF, SIG_IGN);
execvp(next_argv[0], next_argv);
ha_warning("Failed to reexecute the master process [%d]: %s\n", pid, strerror(errno));