linux-kernel - Re: [Linux-v4.6-rc1] ext4: WARNING: CPU: 2 PID: 2692 at kernel/locking/lockdep.c:2017 __lock

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: <20160329084701.GA9393@gmail.com>
Date:	Tue, 29 Mar 2016 10:47:02 +0200
From:	Ingo Molnar <mingo@...nel.org>
To:	Peter Zijlstra <peterz@...radead.org>,
	Alfredo Alvarez Fernandez <alfredoalvarezfernandez@...il.com>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	Sedat Dilek <sedat.dilek@...il.com>,
	Theodore Ts'o <tytso@....edu>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	LKML <linux-kernel@...r.kernel.org>
Subject: Re: [Linux-v4.6-rc1] ext4: WARNING: CPU: 2 PID: 2692 at
 kernel/locking/lockdep.c:2017 __lock_acquire+0x180e/0x2260


* Peter Zijlstra <peterz@...radead.org> wrote:

> On Sun, Mar 27, 2016 at 05:03:44AM -0700, Linus Torvalds wrote:
> > Anyway, I don't think that DEBUG_LOCKS_WARN_ON() in
> > 
> >   kernel/locking/lockdep.c:2017 __lock_acquire
> > 
> > would be an ext4 issue, it looks more like an internal lockdep issue.
> > 
> > Adding in the lockdep people, who will set me right.
> 
> You are right; this is lockdep running into a hash collision; which is a new 
> DEBUG_LOCKDEP test. See 9e4e7554e755 ("locking/lockdep: Detect chain_key 
> collisions").

I've Cc:-ed Alfredo Alvarez Fernandez who added that test.

Thanks,

	Ingo