linux-kernel - Re: RAID1 might_sleep() warning on 3.19-rc7

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20150210110116.GP24151@twins.programming.kicks-ass.net>
Date:	Tue, 10 Feb 2015 12:01:16 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	NeilBrown <neilb@...e.de>
Cc:	Tony Battersby <tonyb@...ernetics.com>, linux-raid@...r.kernel.org,
	lkml <linux-kernel@...r.kernel.org>, axboe@...nel.dk,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: RAID1 might_sleep() warning on 3.19-rc7

On Tue, Feb 10, 2015 at 10:29:36AM +0100, Peter Zijlstra wrote:
> On Tue, Feb 10, 2015 at 01:50:17PM +1100, NeilBrown wrote:
> > On Mon, 9 Feb 2015 10:10:00 +0100 Peter Zijlstra <peterz@...radead.org> wrote:
> > > > However, when io_schedule() explicitly calls blk_flush_plug(), then
> > > > @from_schedule=false variant is used, and the unplug functions are allowed to
> > > > allocate memory and block and maybe even call mempool_alloc() which might
> > > > call io_schedule().

Note that as it stands recursively calling io_schedule() is already
broken. Things like delayacct_blkio_{start,end}() do not nest properly.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/