On Mon, Nov 6, 2017 at 11:39 AM, Takashi Iwai tiwai@suse.de wrote:
On Thu, 02 Nov 2017 10:09:51 +0100, Kirill A. Shutemov wrote:
On Thu, Nov 02, 2017 at 09:23:58AM +0100, Takashi Iwai wrote:
Currently the least ALSA timer interrupt period is limited to 1ms. Does it still too much?
Can the reproducer triggers it reliably? If yes, could you forward it, too (and config as well), so that I'll try to dig down more exact code paths?
All of that is part of original report:
http://lkml.kernel.org/r/94eb2c19df188b1926055cf13c21@google.com
marc.info hasn't stored repro.c for some reasone. Attached.
I've just check it reproduces reliably for me in KVM.
I also checked that it's not specific to THP -- still trigirable with huge pages disabled.
I guess this is the same issue Jerome forwarded recently, and it was fixed by limiting the amount of ALSA timer instances. I queued the fix in sound git tree for-linus branch, commit 9b7d869ee5a77ed4a462372bb89af622e705bfb8 ALSA: timer: Limit max instances per timer
It'll be likely included in 4.14 final.
Thanks
Let's also tell the bot what fixes this:
#syz fix: ALSA: timer: Limit max instances per timer