linux-kernel - Re: [PATCH][-mm] reclassify sg_sysfs

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]

Message-Id: <1211985600.3445.14.camel@localhost.localdomain>
Date:	Wed, 28 May 2008 09:40:00 -0500
From:	James Bottomley <James.Bottomley@...senPartnership.com>
To:	Dave Young <hidave.darkstar@...il.com>
Cc:	akpm@...ux-foundation.org, greg@...ah.com, matthew@....cx,
	kay.sievers@...y.org, linux-kernel@...r.kernel.org,
	linux-scsi@...r.kernel.org
Subject: Re: [PATCH][-mm] reclassify sg_sysfs_class for lockdep

On Tue, 2008-05-27 at 18:10 +0800, Dave Young wrote:
> As register sg_interface, the sg_add will be called, which then will
> add device to sg_sysfs_class. This will cause lockdep warning,
> please see following email
> 
> In this case the locks are from diffrent classi, one is sdev_class,
> another is sg_sysfs_class 
> 
> Here reclassify the sg_sysfs_class for lockdep

This isn't really a generic solution, is it?  It only works because we
currently only have two users of the interface functions, so if we
reclassify one they look separate to lockdep.  It will fall over again
if we ever get another one.

Surely the correct fix is to initialise lockdep for the mutex the same
way we did for the semaphore in class_register() (which does exactly the
same locking without triggering lockdep)?  That way we'll also fix the
problem for other conversions of semaphore->mutex.

James

--
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/