diff --git a/miscutils/watchdog.c b/miscutils/watchdog.c index 893cef0ac..e334d0189 100644 --- a/miscutils/watchdog.c +++ b/miscutils/watchdog.c @@ -45,6 +45,15 @@ int watchdog_main(int argc, char **argv) opt_complementary = "=1"; /* must have exactly 1 argument */ opts = getopt32(argv, "Ft:T:", &st_arg, &ht_arg); + /* We need to daemonize *before* opening the watchdog as many drivers + * will only allow one process at a time to do so. Since daemonizing + * is not perfect (child may run before parent finishes exiting), we + * can't rely on parent exiting before us (let alone *cleanly* releasing + * the watchdog fd -- something else that may not even be allowed). + */ + if (!(opts & OPT_FOREGROUND)) + bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv); + if (opts & OPT_HTIMER) htimer_duration = xatou_sfx(ht_arg, suffixes); stimer_duration = htimer_duration / 2; @@ -76,10 +85,6 @@ int watchdog_main(int argc, char **argv) stimer_duration, htimer_duration * 1000); #endif - if (!(opts & OPT_FOREGROUND)) { - bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv); - } - while (1) { /* * Make sure we clear the counter before sleeping,