From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ve0-f178.google.com (mail-ve0-f178.google.com [209.85.128.178]) by kanga.kvack.org (Postfix) with ESMTP id E29D96B0035 for ; Wed, 23 Apr 2014 11:07:18 -0400 (EDT) Received: by mail-ve0-f178.google.com with SMTP id jw12so1341121veb.9 for ; Wed, 23 Apr 2014 08:07:18 -0700 (PDT) Received: from mail-vc0-x234.google.com (mail-vc0-x234.google.com [2607:f8b0:400c:c03::234]) by mx.google.com with ESMTPS id cb3si212597vdc.167.2014.04.23.08.07.16 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Wed, 23 Apr 2014 08:07:16 -0700 (PDT) Received: by mail-vc0-f180.google.com with SMTP id hy4so1270921vcb.25 for ; Wed, 23 Apr 2014 08:07:16 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20140423144901.GA24220@redhat.com> References: <20140422180308.GA19038@redhat.com> <20140423144901.GA24220@redhat.com> Date: Wed, 23 Apr 2014 08:07:16 -0700 Message-ID: Subject: Re: 3.15rc2 hanging processes on exit. From: Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Dave Jones , Hugh Dickins , Linus Torvalds , Linux Kernel , linux-mm On Wed, Apr 23, 2014 at 7:49 AM, Dave Jones wrote: > > So for reasons I can't figure out, I've not been able to hit it on 3.14 > The only 'interesting' thing I've hit in overnight testing is this, which > I'm not sure if I've also seen in my .15rc testing, but it doesn't look > familiar to me. (Though the vm oopses I've seen the last few months > are starting to all blur together in my memory) > > > kernel BUG at mm/mlock.c:82! That's mlock_vma_page: BUG_ON(!PageLocked(page)); which is odd, because: > Call Trace: > [] try_to_unmap_nonlinear+0x2a2/0x530 > [] rmap_walk+0x157/0x320 > [] try_to_unmap+0x93/0xf0 > [] migrate_pages+0x3b6/0x7b0 All the calls to "try_to_unmap()" in mm/migrate.c are preceded by the pattern if (!trylock_page(page)) { .... lock_page(page); } where there are just a few "goto out" style cases for the "ok, we're not going to wait for this page lock" in there. Very odd. Does anybody see anything I missed? Linus -- 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