From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pb0-f47.google.com (mail-pb0-f47.google.com [209.85.160.47]) by kanga.kvack.org (Postfix) with ESMTP id 75D6F6B0035 for ; Thu, 23 Jan 2014 01:06:12 -0500 (EST) Received: by mail-pb0-f47.google.com with SMTP id rp16so1418034pbb.20 for ; Wed, 22 Jan 2014 22:06:12 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTP id i8si12663466pav.161.2014.01.22.22.06.10 for ; Wed, 22 Jan 2014 22:06:11 -0800 (PST) Date: Wed, 22 Jan 2014 22:09:10 -0800 From: Andrew Morton Subject: Re: [Bug 67651] Bisected: Lots of fragmented mmaps cause gimp to fail in 3.12 after exceeding vm_max_map_count Message-Id: <20140122220910.198121ee.akpm@linux-foundation.org> In-Reply-To: <20140123055906.GS1574@moon> References: <20140122190816.GB4963@suse.de> <52E04A21.3050101@mit.edu> <20140123055906.GS1574@moon> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Cyrill Gorcunov Cc: Andy Lutomirski , Mel Gorman , Pavel Emelyanov , gnome@rvzt.net, drawoc@darkrefraction.com, alan@lxorguk.ukuu.org.uk, linux-mm@kvack.org, linux-kernel@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org On Thu, 23 Jan 2014 09:59:06 +0400 Cyrill Gorcunov wrote: > On Wed, Jan 22, 2014 at 02:45:53PM -0800, Andy Lutomirski wrote: > > > > > > Thus when user space application track memory changes now it can detect if > > > vma area is renewed. > > > > Presumably some path is failing to set VM_SOFTDIRTY, thus preventing mms > > from being merged. > > > > That being said, this could cause vma blowups for programs that are > > actually using this thing. > > Hi Andy, indeed, this could happen. The easiest way is to ignore softdirty bit > when we're trying to merge vmas and set it one new merged. I think this should > be correct. Once I finish I'll send the patch. Hang on. We think the problem is that gimp is generating vmas which *should* be merged, but for unknown reasons they differ in VM_SOFTDIRTY, yes? Shouldn't we work out where we're forgetting to set VM_SOFTDIRTY? Putting bandaids over this error when we come to trying to merge the vmas sounds very wrong? -- 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