From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f177.google.com (mail-pd0-f177.google.com [209.85.192.177]) by kanga.kvack.org (Postfix) with ESMTP id E03EC6B013D for ; Tue, 18 Mar 2014 22:13:09 -0400 (EDT) Received: by mail-pd0-f177.google.com with SMTP id y10so7938258pdj.36 for ; Tue, 18 Mar 2014 19:13:09 -0700 (PDT) Received: from mail-pb0-x235.google.com (mail-pb0-x235.google.com [2607:f8b0:400e:c01::235]) by mx.google.com with ESMTPS id tv5si10861354pbc.89.2014.03.18.19.13.08 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 18 Mar 2014 19:13:08 -0700 (PDT) Received: by mail-pb0-f53.google.com with SMTP id rp16so8174367pbb.12 for ; Tue, 18 Mar 2014 19:13:08 -0700 (PDT) Date: Tue, 18 Mar 2014 19:12:14 -0700 (PDT) From: Hugh Dickins 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> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: 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 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org