From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758908AbaCSCNK (ORCPT ); Tue, 18 Mar 2014 22:13:10 -0400 Received: from mail-pd0-f171.google.com ([209.85.192.171]:37958 "EHLO mail-pd0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758511AbaCSCNJ (ORCPT ); Tue, 18 Mar 2014 22:13:09 -0400 Date: Tue, 18 Mar 2014 19:12:14 -0700 (PDT) From: Hugh Dickins X-X-Sender: hugh@eggly.anvils To: Sasha Levin cc: Hugh Dickins , Dave Jones , Cyrill Gorcunov , Andrew Morton , Linux Kernel , linux-mm@kvack.org, Linus Torvalds , Joonsoo Kim , Bob Liu , Konstantin Khlebnikov Subject: Re: bad rss-counter message in 3.14rc5 In-Reply-To: <5328F3B4.1080208@oracle.com> Message-ID: References: <20140311045109.GB12551@redhat.com> <20140310220158.7e8b7f2a.akpm@linux-foundation.org> <20140311053017.GB14329@redhat.com> <20140311132024.GC32390@moon> <531F0E39.9020100@oracle.com> <20140311134158.GD32390@moon> <20140311142817.GA26517@redhat.com> <20140311143750.GE32390@moon> <20140311171045.GA4693@redhat.com> <20140311173603.GG32390@moon> <20140311173917.GB4693@redhat.com> <5328F3B4.1080208@oracle.com> 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 On Tue, 18 Mar 2014, Sasha Levin wrote: > On 03/18/2014 08:38 PM, Hugh Dickins wrote: > > On Tue, 11 Mar 2014, Dave Jones wrote: > > > On Tue, Mar 11, 2014 at 09:36:03PM +0400, Cyrill Gorcunov wrote: > > > > On Tue, Mar 11, 2014 at 01:10:45PM -0400, Dave Jones wrote: > > > > > > > > > > > > Dave, iirc trinity can write log file pointing which exactly > > > syscall sequence > > > > > > was passed, right? Share it too please. > > > > > > > > > > Hm, I may have been mistaken, and the damage was done by a previous > > > run. > > > > > I went from being able to reproduce it almost instantly to now not > > > being able > > > > > to reproduce it at all. Will keep trying. > > > > > > > > Sasha already gave a link to the syscalls sequence, so no rush. > > > > > > It'd be nice to get a more concise reproducer, his list had a little of > > > everything in there. > > > > I've so far failed to find any explanation for your swapops.h BUG; > > but believe I have identified one cause for "Bad rss-counter"s. > > > > My hunch is that the swapops.h BUG is "nearby", but I just cannot > > fit it together (the swapops.h BUG comes when rmap cannot find all > > all the migration entries it inserted earlier: it's a very useful > > BUG for validating rmap). > > > > Untested patch below: I can't quite say Reported-by, because it may > > not even be one that you and Sasha have been seeing; but I'm hopeful, > > remap_file_pages is in the list. > > > > Please give this a try, preferably on 3.14-rc or earlier: I've never > > seen "Bad rss-counter"s there myself (trinity uses remap_file_pages > > a lot more than most of us); but have seen them on mmotm/next, so > > some other trigger is coming up there, I'll worry about that once > > it reaches 3.15-rc. > > The patch fixed the "Bad rss-counter" errors I've been seeing both in > 3.14-rc7 and -next. Great, thanks a lot, Sasha. I was afraid that you'd hit those swapops BUGs, which seemed perhaps to be paired with these; but glad to hear a positive. Let's see how Dave fares. (I've not forgotten shmem fallocate, by the way, but those probably aren't as high on my agenda as you'd like.) Hugh