tree 9095cf6f07b86a43df416c7ebdd261967935053d
parent d17344b3547669f5b6ee4fda993d03737a141bd6
author Omair Mohammed Abdullah <omair.m.abdullah@linux.intel.com> 1348901645 +0530
committer Takashi Iwai <tiwai@suse.de> 1349535028 +0200

ALSA: aloop - add locking to timer access

When the loopback timer handler is running, calling del_timer() (for STOP
trigger) will not wait for the handler to complete before deactivating the
timer. The timer gets rescheduled in the handler as usual. Then a subsequent
START trigger will try to start the timer using add_timer() with a timer pending
leading to a kernel panic.

Serialize the calls to add_timer() and del_timer() using a spin lock to avoid
this.

Signed-off-by: Omair Mohammed Abdullah <omair.m.abdullah@linux.intel.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>