From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds Subject: Re: [PULL REQUEST] md bug fixes and minor improvements Date: Fri, 1 Aug 2008 10:16:57 -0700 (PDT) Message-ID: References: <18578.31924.259887.735206@notabene.brown> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <18578.31924.259887.735206@notabene.brown> Sender: linux-raid-owner@vger.kernel.org To: Neil Brown Cc: Arthur Jones , Dan Williams , Linux Kernel Mailing List , linux-raid@vger.kernel.org, "Rafael J. Wysocki" , Jens Axboe List-Id: linux-raid.ids On Fri, 1 Aug 2008, Neil Brown wrote: > > Hi Linus, > please pull the following bugfixes for drivers/md. Hmm. This doesn't seem to include any fix for the reported unlocked blk_plug() from MD? See the emails from Rafael on the kernel mailing list for details (WARNING: at /home/rafael/src/linux-next/include/linux/blkdev.h:447), but it boils down to WARNING: at /home/rafael/src/linux-2.6/include/linux/blkdev.h:447 blk_plug_device+0x9b/0xb0() Pid: 2268, comm: kjournald Not tainted 2.6.27-rc1-git #211 Call Trace: [] warn_on_slowpath+0x5f/0x80 [] blk_plug_device+0x9b/0xb0 [] bitmap_startwrite+0xbf/0x1b0 where it really looks like "bitmap_startwrite()" just calls blk_plug_device() without holding the queue lock. The rule for that function is documented to be: * This is called with interrupts off and no requests on the queue and * with the queue lock held. Hmm? Now, admittedly, the blk interfaces here are a bit inconsistent: I think blk_unplug() is supposed to be called _without_ the lock, so it's a bit odd that blk_plug_device() is supposed to b called with it held, but somebody should double-check me on that one. I guess Jens is gone too.. Linus