From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from linuxhacker.ru ([217.76.32.60]:58224 "EHLO fiona.linuxhacker.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752243AbcFCSfr convert rfc822-to-8bit (ORCPT ); Fri, 3 Jun 2016 14:35:47 -0400 Subject: Re: Dcache oops Mime-Version: 1.0 (Apple Message framework v1283) Content-Type: text/plain; charset=us-ascii From: Oleg Drokin In-Reply-To: <20160603182203.GR14480@ZenIV.linux.org.uk> Date: Fri, 3 Jun 2016 14:35:41 -0400 Cc: " Mailing List" , "" , Linus Torvalds Content-Transfer-Encoding: 8BIT Message-Id: <4285E00F-7228-485C-AD32-97552ED746F2@linuxhacker.ru> References: <20160603033750.GL14480@ZenIV.linux.org.uk> <0C971585-6BFC-4665-832B-9B262F733BFC@linuxhacker.ru> <20160603042648.GN14480@ZenIV.linux.org.uk> <74306F63-DBDF-4DED-85D2-5C3FB21B8A1E@linuxhacker.ru> <20160603182203.GR14480@ZenIV.linux.org.uk> To: Al Viro Sender: linux-fsdevel-owner@vger.kernel.org List-ID: On Jun 3, 2016, at 2:22 PM, Al Viro wrote: > On Fri, Jun 03, 2016 at 12:38:40PM -0400, Oleg Drokin wrote: >> I am dropping NFS people since it seems to be converting into a generic VFS/dcache bug even though you need NFS or the like to trigger it - the lookup_open path. > > NFS bug is real; there might very well be something else, but that d_drop() > in nfs_atomic_open() needs to be restored. Yes, that's what I mean - after the nfs fix, there seems to be another bug in dcache that I can now trigger once nfs bug is no longer blocking the way. >> [ 2642.364383] BUG: unable to handle kernel paging request at ffff880113f82000 >> [ 2642.365014] IP: [] bad_gs+0xd1d/0x1ba9 > > *ow* > Could you dump your vmlinux (and System.map) somewhere on anonftp? > This 'bad_gs' is there simply because it's one of the few labels in > .fixup - to say anything useful we'll need to find out where we'd > really come from. I see. vmlinux with debug symbols: http://knox.linuxhacker.ru/tmp/dcache/vmlinux.gz System.map: http://knox.linuxhacker.ru/tmp/dcache/System.map.gz >> Hm, somehow crashdumping support is broken for the newish kernels on my test box, I guess >> I'll try to fix it and then re-reproduce to better understand what's going on here, >> this trace is all I have for now in case anybody has any immediate ideas. > > PS: Oleg, fix your MUA, please - long lines in mail are bloody annoying. Huh, sorry about that. I kind of hoped the era of 80 columns text terminals was mostly behind us. Time to dust off mutt, I guess.