Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757566AbaAHVSz (ORCPT ); Wed, 8 Jan 2014 16:18:55 -0500 Received: from mail-pa0-f44.google.com ([209.85.220.44]:34289 "EHLO mail-pa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932192AbaAHVSr (ORCPT ); Wed, 8 Jan 2014 16:18:47 -0500 MIME-Version: 1.0 In-Reply-To: <20140108211454.GC7291@kmo-pixel> References: <1389126617.23310.19.camel@ret.masoncoding.com> <1389210102.23310.31.camel@ret.masoncoding.com> <1389212231.23310.33.camel@ret.masoncoding.com> <1389214325.23310.34.camel@ret.masoncoding.com> <1389215536.23310.37.camel@ret.masoncoding.com> <20140108211454.GC7291@kmo-pixel> Date: Wed, 8 Jan 2014 13:18:46 -0800 Message-ID: Subject: Re: [block:for-3.14/core] kernel BUG at fs/bio.c:1748 From: Muthu Kumar To: Kent Overstreet Cc: Chris Mason , "linux-btrfs@vger.kernel.org" , "fengguang.wu@intel.com" , "linux-kernel@vger.kernel.org" , "lkp@linux.intel.com" , "axboe@kernel.dk" , "linux-fsdevel@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 8, 2014 at 1:14 PM, Kent Overstreet wrote: > On Wed, Jan 08, 2014 at 09:11:49PM +0000, Chris Mason wrote: >> On Wed, 2014-01-08 at 13:01 -0800, Muthu Kumar wrote: >> > On Wed, Jan 8, 2014 at 12:51 PM, Chris Mason wrote: >> > > On Wed, 2014-01-08 at 12:40 -0800, Muthu Kumar wrote: >> > >> On Wed, Jan 8, 2014 at 12:16 PM, Chris Mason wrote: >> > >> > On Wed, 2014-01-08 at 11:54 -0800, Muthu Kumar wrote: >> > >> >> Chris, >> > >> >> >> > >> >> [ 8.336061] WARNING: CPU: 0 PID: 0 at fs/bio.c:1778 bio_endio+0xbe/0x100() >> > >> >> [ 8.336062] bio_endio: bio for (unknown) without endio >> > >> >> >> > >> >> This is my recent change to avoid memory leak in bio_endio. But I >> > >> >> think the problem is higher up, most likely bio_endio is called twice >> > >> >> on the same bio (which was freed before). >> > >> >> >> > >> > >> > >> > I think these are just two separate problems. Lets ignore the WARN_ON >> > >> > for now. >> > >> > >> > >> >> > >> Not really... the BUG that is triggered: >> > >> >> > >> kernel BUG at fs/bio.c:523! >> > >> >> > >> It is in bio_put() (added to bio_endio() as part of recent change) >> > >> which gets an already freed bio. >> > >> >> > > >> > > Oh! I see. Let me try with that one reverted. Thanks! >> > > >> > > -chris >> > > >> > >> > But, like I said, problem is in different place. I am running a "dd" >> > on ext4 fs for a while now, but didn't hit the problem. Any idea to >> > repro locally? I would also suggest running just the for-3.1/core to >> > isolate the issue. >> >> Just reverting that change fixes it for me. Jens mentioned it was >> broken for on-stack bios. > > On-stack bios? I don't recall ever coming across such a thing, who what > where why? > > i would expect on stack bios to work though, i'm really curious how it > was broken New change added a bio_put() which might not work if the bio is on stack. I don't remember seeing a on-stack-bio either, any help to jog my memory? -- 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/