Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752613AbdFTJGF (ORCPT ); Tue, 20 Jun 2017 05:06:05 -0400 Received: from mail-pf0-f181.google.com ([209.85.192.181]:34032 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752407AbdFTJGC (ORCPT ); Tue, 20 Jun 2017 05:06:02 -0400 Date: Tue, 20 Jun 2017 02:05:53 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Dave Jones , Hugh Dickins , Linus Torvalds , Linux Kernel Mailing List , Oleg Nesterov , Michal Hocko Subject: Re: Linux 4.12-rc6 In-Reply-To: <20170620034222.nykxdbagaqa3rqni@codemonkey.org.uk> Message-ID: References: <20170620002612.bwjphlk2qz3ynghl@codemonkey.org.uk> <20170620034222.nykxdbagaqa3rqni@codemonkey.org.uk> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 851 Lines: 25 On Mon, 19 Jun 2017, Dave Jones wrote: > > I hacked up this harness to try and narrow it down more.. > > #!/bin/bash > > . scripts/taint.sh > > while [ 1 ]; > do > ./trinity -a64 -C1 -c mmap -N1 --enable-fds=testfile > check_tainted > done Very helpful reproducer, thank you Dave: I tried a couple of times, and it crashed in about 3 minutes each time. And good news is that the check that Linus suggested does indeed fix it. I'm anxious to send the patch in now, so have only tested about half an hour on x86_64 and half an hour x86_32 so far, just to make sure that at least there isn't something too embarrassing just around this first corner (some of the time with ulimit -s at default 8192, some of the time unlimited, since that affects layout decisions). I'll send in the patch now - many thanks for catching this so quickly. Hugh