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Date: Tue, 06 Sep 2016 18:10:30 +0200
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From: Takashi Iwai <tiwai@suse.de>
To: Dmitry Vyukov <dvyukov@google.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>,
        Vegard Nossum <vegard.nossum@oracle.com>,
        Jaroslav Kysela <perex@perex.cz>, Kangjie Lu <kangjielu@gmail.com>,
        alsa-devel@alsa-project.org, LKML <linux-kernel@vger.kernel.org>,
        syzkaller <syzkaller@googlegroups.com>
Subject: Re: sound: divide by 0 in snd_hrtimer_callback (or hang)
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On Tue, 06 Sep 2016 16:06:08 +0200,
Dmitry Vyukov wrote:
> 
> > Do you really see the zero-division error with sticks=1 fix?  That's
> > unexpected.
> 
> Yes, just reproduced it again.
> I am on 0693c28cfc8e25f18c25b65a8942c026f1854a3c of linux-next now, so
> I already have:
>     commit 6b760bb2c63a9e322c0e4a0b5daf335ad93d5a33
>     ALSA: timer: fix division by zero after SNDRV_TIMER_IOCTL_CONTINUE
> 
> Compiled the program verbatim and run it using stress utility (http
> s://godoc.org/golang.org/x/tools/cmd/stress namely just runs the
> program in parallel loop) and instantly get the following crash.

OK, I'll take a deeper look.


thanks,

Takashi