[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Tue, 2 Feb 2016 22:24:04 +0100 (CET)
From: Jiri Kosina <jikos@...nel.org>
To: Dmitry Vyukov <dvyukov@...gle.com>
cc: Andrew Morton <akpm@...ux-foundation.org>,
"Kirill A. Shutemov" <kirill.shutemov@...ux.intel.com>,
Oleg Nesterov <oleg@...hat.com>,
Konstantin Khlebnikov <koct9i@...il.com>,
"linux-mm@...ck.org" <linux-mm@...ck.org>,
LKML <linux-kernel@...r.kernel.org>,
Takashi Iwai <tiwai@...e.de>,
syzkaller <syzkaller@...glegroups.com>,
Kostya Serebryany <kcc@...gle.com>,
Alexander Potapenko <glider@...gle.com>,
Sasha Levin <sasha.levin@...cle.com>
Subject: Re: mm: uninterruptable tasks hanged on mmap_sem
On Tue, 2 Feb 2016, Dmitry Vyukov wrote:
> Original log from fuzzer contained the following WARNING in
> mm/rmap.c:412. But when I tried to reproduce it, I hit these hanged
> processes instead. I can't reliably detect what program triggered
> what. So it may be related, or maybe a separate issue.
>
> ------------[ cut here ]------------
> kernel BUG at mm/rmap.c:412!
Are you by any chance in this test sending signals to the fuzzer?
If so, the bug I just fixed in floppy driver can cause all kinds of memory
corruptions in case you're running multithreaded accessess to /dev/fd0 and
sending singals to the threads that are trying to access /dev/fd0 at the
same time.
Could you please double check that the other floppy fix I've sent you a
couple days ago doesn't fix this as well? (this test makes sense only if
signals are involved though).
Thanks,
--
Jiri Kosina
SUSE Labs
Powered by blists - more mailing lists