mirror of https://gitee.com/openkylin/linux.git
4a07083ed6
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> |
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| .. | ||
| oss | ||
| seq | ||
| Kconfig | ||
| Makefile | ||
| compress_offload.c | ||
| control.c | ||
| control_compat.c | ||
| ctljack.c | ||
| device.c | ||
| hrtimer.c | ||
| hwdep.c | ||
| hwdep_compat.c | ||
| info.c | ||
| info_oss.c | ||
| init.c | ||
| isadma.c | ||
| jack.c | ||
| memalloc.c | ||
| memory.c | ||
| misc.c | ||
| pcm.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 | ||
| rawmidi.c | ||
| rawmidi_compat.c | ||
| rtctimer.c | ||
| sgbuf.c | ||
| sound.c | ||
| sound_oss.c | ||
| timer.c | ||
| timer_compat.c | ||
| vmaster.c | ||