Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965859AbdLSBWR (ORCPT ); Mon, 18 Dec 2017 20:22:17 -0500 Received: from scorn.kernelslacker.org ([45.56.101.199]:44734 "EHLO scorn.kernelslacker.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935396AbdLSBWQ (ORCPT ); Mon, 18 Dec 2017 20:22:16 -0500 Date: Mon, 18 Dec 2017 20:22:14 -0500 From: Dave Jones To: Linus Torvalds Cc: Al Viro , Linux Kernel Subject: Re: proc_flush_task oops Message-ID: <20171219012214.GA19673@codemonkey.org.uk> Mail-Followup-To: Dave Jones , Linus Torvalds , Al Viro , Linux Kernel References: <20171218214438.GA32728@codemonkey.org.uk> <20171218221541.GP21978@ZenIV.linux.org.uk> <20171218231013.GA9481@codemonkey.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.2 (2017-12-15) X-Spam-Note: SpamAssassin invocation failed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1032 Lines: 24 On Mon, Dec 18, 2017 at 03:50:52PM -0800, Linus Torvalds wrote: > On Mon, Dec 18, 2017 at 3:10 PM, Dave Jones wrote: > > On Mon, Dec 18, 2017 at 10:15:41PM +0000, Al Viro wrote: > > > On Mon, Dec 18, 2017 at 04:44:38PM -0500, Dave Jones wrote: > > > > I've hit this twice today. It's odd, because afaics, none of this code > > > > has really changed in a long time. > > > > > > Which tree had that been? > > > > Linus, rc4. > > Ok, so the original report was marked as spam for me for whatever > reason. I ended up re-analyzing the oops, but came to the same > conclusion you did: it's a NULL mnt pointer in proc_flush_task_mnt(). > .. > But I don't see what would have changed in this area recently. > > Do you end up saving the seeds that cause crashes? Is this > reproducible? (Other than seeing it twoce, of course) Hit it another two times in the last hour, so it's pretty reproducable. Running it now with some more logging, will see if that yields any extra clues. Dave