On Tue, Mar 1, 2016 at 3:44 PM, Takashi Iwai tiwai@suse.de wrote:
On Tue, 01 Mar 2016 13:33:27 +0100, Dmitry Vyukov wrote:
Hello,
The following program creates an unkillable process:
.....
The hang stack is:
[<ffffffff85309f77>] snd_seq_oss_writeq_sync+0x327/0x790 sound/core/seq/oss/seq_oss_writeq.c:121
This is wait_event_interruptible_timeout(q->sync_sleep, ! q->sync_event_put, HZ);
and this should return zero if (signal_pending(current)) /* interrupted - return 0 to finish sync */ q->sync_event_put = 0; if (! q->sync_event_put || q->sync_time >= time) return 0; return 1;
[<ffffffff852fa353>] snd_seq_oss_drain_write+0x113/0x160
... and this loop should break: while (snd_seq_oss_writeq_sync(dp->writeq)) ;
So, I see no obvious error in the code, so far.
I'm running your test program now with 8 parallel runs, but I couldn't reproduce it. Any other specifics?
thanks,
Takashi