Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752473Ab0HASBm (ORCPT ); Sun, 1 Aug 2010 14:01:42 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:42273 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750940Ab0HASBj convert rfc822-to-8bit (ORCPT ); Sun, 1 Aug 2010 14:01:39 -0400 MIME-Version: 1.0 In-Reply-To: <2dWFdr9kTFM.A.P0D.spXVMB@chimera> References: <2dWFdr9kTFM.A.P0D.spXVMB@chimera> From: Linus Torvalds Date: Sun, 1 Aug 2010 11:01:04 -0700 Message-ID: Subject: Re: 2.6.35-rc6-git6: Reported regressions from 2.6.34 To: "Rafael J. Wysocki" , Jens Axboe , Tejun Heo Cc: Linux Kernel Mailing List , Maciej Rutecki , Andrew Morton , Kernel Testers List , Network Development , Linux ACPI , Linux PM List , Linux SCSI List , Linux Wireless List , DRI Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3765 Lines: 85 On Sun, Aug 1, 2010 at 6:46 AM, Rafael J. Wysocki wrote: > > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=16400 > Subject : 2.6.35-rc5 inconsistent lock state > Submitter : Martin Pirker > Date : 2010-07-14 20:33 (19 days old) > Message-ID : > References : http://marc.info/?l=linux-kernel&m=127913961025267&w=2 This has a proposed patch. I don't know what the status of it is, though. Jens? http://marc.info/?l=linux-kernel&m=127950018204029&w=2 > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=16393 > Subject : kernel BUG at fs/block_dev.c:765! > Submitter : Markus Trippelsdorf > Date : 2010-07-14 13:52 (19 days old) > Message-ID : <20100714135217.GA1797@arch.tripp.de> > References : http://marc.info/?l=linux-kernel&m=127911564213748&w=2 This one is interesting. And I think I perhaps see where it's coming from. bd_start_claiming() (through bd_prepare_to_claim()) has two separate success cases: either there was no holder (bd_claiming is NULL) or the new holder was already claiming it (bd_claiming == holder). Note in particular the case of the holder _already_ holding it. What happens is: - bd_start_claiming() succeeds because we had _already_ claimed it with the same holder - then some error happens, and we call bd_abort_claiming(), which does whole->bd_claiming = NULL; - the original holder thinks it still holds the bd, but it has been released! - a new claimer comes in, and succeeds because bd_claiming is now NULL. - we now have two "owners" of the bd, but bd_claiming only points to the second one. I think bd_start_claiming() needs to do some kind of refcount for the nested holder case, and bd_abort_claiming() needs to decrement the refcount and only clear the bd_claiming field when it goes down to zero. I dunno. Maybe there's something else going on, but it does look suspicious, and the above would explain the BUG_ON(). Tejun, Jens? > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=16369 > Subject : Yet another 2.6.35 regression (AGP)? > Submitter : Woody Suwalski > Date : 2010-07-09 14:21 (24 days old) > Message-ID : <4C373084.8000503@gmail.com> > References : http://marc.info/?l=linux-kernel&m=127868797119254&w=2 Should hopefully be fixed by commit e7b96f28c58c ("agp/intel: Use the correct mask to detect i830 aperture size.") > Bug-Entry : http://bugzilla.kernel.org/show_bug.cgi?id=16365 > Subject : kernel BUG at fs/btrfs/extent-tree.c:1353 > Submitter : Johannes Hirte > Date : 2010-07-08 14:27 (25 days old) > Message-ID : <201007081627.24654.johannes.hirte@fem.tu-ilmenau.de> > References : http://marc.info/?l=linux-kernel&m=127859960725931&w=2 This one is reportedly fixed by commit 83ba7b071f30 ("writeback: simplify the write back thread queue") > Bug-Entry ? ? ? : http://bugzilla.kernel.org/show_bug.cgi?id=16215 > Subject ? ? ? ? : sysfs: cannot create duplicate filename '/class/net/bnep0' > Submitter ? ? ? : Janusz Krzysztofik > Date ? ? ? ? ? ?: 2010-06-15 14:55 (48 days old) > Handled-By ? ? ?: Eric W. Biederman Fixed by commit 24b1442d01ae155ea716dfb94ed21605541c317d. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/