Currently alsactl-restore tries to initialize the device when an error is found for restore action. But this isn't the right behavior in the case where the lock is held; it implies that another alsactl is running concurrently, hence you shouldn't initialize the card at the same time. The situation is found easily when two alsactls get started by both udev and systemd (note that those two invocations are the designed behavior, see /usr/lib/udev/rules.d/78-sound-cards.rules for details).
This patch changes load_state() not to handle the initialization if the locking fails.
BugLink: https://bugzilla.opensuse.org/show_bug.cgi?id=1179904 Signed-off-by: Takashi Iwai tiwai@suse.de --- alsactl/state.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/alsactl/state.c b/alsactl/state.c index ea1d3bcaaddf..8d1d814341bd 100644 --- a/alsactl/state.c +++ b/alsactl/state.c @@ -1663,7 +1663,12 @@ int load_state(const char *file, const char *initfile, int initflags, err = snd_input_stdio_attach(&in, stdin, 0); } else { lock_fd = state_lock(file, 10); - err = lock_fd >= 0 ? snd_input_stdio_open(&in, file, "r") : lock_fd; + /* skip restore if already locked; i.e. concurrent accesses */ + if (lock_fd < 0) { + err = 0; + goto out_global; + } + err = snd_input_stdio_open(&in, file, "r"); } if (err >= 0) { err = snd_config_load(config, in); @@ -1781,6 +1786,7 @@ single: err = finalerr; out: snd_config_delete(config); +out_global: snd_config_update_free_global(); return err; }