Takashi Iwai 4a07083ed6 ALSA: timer: Use mod_timer() for rearming the system timer ... ALSA system timer backend stops the timer via del_timer() without sync and leaves del_timer_sync() at the close instead. This is because of the restriction by the design of ALSA timer: namely, the stop callback may be called from the timer handler, and calling the sync shall lead to a hangup. However, this also triggers a kernel BUG() when the timer is rearmed immediately after stopping without sync: kernel BUG at kernel/time/timer.c:966! Call Trace: <IRQ> [<ffffffff8239c94e>] snd_timer_s_start+0x13e/0x1a0 [<ffffffff8239e1f4>] snd_timer_interrupt+0x504/0xec0 [<ffffffff8122fca0>] ? debug_check_no_locks_freed+0x290/0x290 [<ffffffff8239ec64>] snd_timer_s_function+0xb4/0x120 [<ffffffff81296b72>] call_timer_fn+0x162/0x520 [<ffffffff81296add>] ? call_timer_fn+0xcd/0x520 [<ffffffff8239ebb0>] ? snd_timer_interrupt+0xec0/0xec0 .... It's the place where add_timer() checks the pending timer. It's clear that this may happen after the immediate restart without sync in our cases. So, the workaround here is just to use mod_timer() instead of add_timer(). This looks like a band-aid fix, but it's a right move, as snd_timer_interrupt() takes care of the continuous rearm of timer. Reported-by: Jiri Slaby <jslaby@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Takashi Iwai <tiwai@suse.de>		2016-04-01 12:28:16 +02:00
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oss
seq
compress_offload.c
control_compat.c
control.c
ctljack.c
device.c
hrtimer.c
hwdep_compat.c
hwdep.c
info_oss.c
info.c
init.c
isadma.c
jack.c
Kconfig
Makefile
memalloc.c
memory.c
misc.c
pcm_compat.c
pcm_dmaengine.c
pcm_drm_eld.c
pcm_iec958.c
pcm_lib.c
pcm_memory.c
pcm_misc.c
pcm_native.c
pcm_timer.c
pcm_trace.h
pcm.c
rawmidi_compat.c
rawmidi.c
rtctimer.c
sgbuf.c
sound_oss.c
sound.c
timer_compat.c
timer.c
vmaster.c