linux-kernel - Re: [PATCH] cgroups: fix lockdep subclasses overflow

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: Windows password security audit tool. GUI, reports in PDF.

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

Date:	Wed, 04 Feb 2009 17:15:25 +0800
From:	Li Zefan <lizf@...fujitsu.com>
To:	Andrew Morton <akpm@...ux-foundation.org>
CC:	Paul Menage <menage@...gle.com>,
	LKML <linux-kernel@...r.kernel.org>,
	Linux Containers <containers@...ts.linux-foundation.org>
Subject: Re: [PATCH] cgroups: fix lockdep subclasses overflow

Li Zefan wrote:
> I enabled all cgroup subsystems when compiling kernel, and then:
>  # mount -t cgroup -o net_cls xxx /mnt
>  # mkdir /mnt/0
> 
> This showed up immediately:
>  BUG: MAX_LOCKDEP_SUBCLASSES too low!
>  turning off the locking correctness validator.
> 
> It's caused by the cgroup hierarchy lock:
> 	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
> 		struct cgroup_subsys *ss = subsys[i];
> 		if (ss->root == root)
> 			mutex_lock_nested(&ss->hierarchy_mutex, i);
> 	}
> 
> Now we have 9 cgroup subsystems, and the above 'i' for net_cls is 9, but

sorry, a typo here: the above 'i' for net_cls is 8.

> MAX_LOCKDEP_SUBCLASSES is 8.
> 
> This patch uses different lockdep keys for different subsystems.
> 
> Signed-off-by: Li Zefan <lizf@...fujitsu.com>
> ---
--
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/