From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756063AbaFRV3e (ORCPT ); Wed, 18 Jun 2014 17:29:34 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:42187 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755455AbaFRV3c (ORCPT ); Wed, 18 Jun 2014 17:29:32 -0400 Date: Wed, 18 Jun 2014 14:29:31 -0700 From: Andrew Morton To: Heiko Carstens Cc: David Rientjes , Ian Kent , Hendrik Brueckner , Thorsten Diehl , Andrea Righi , Christoph Hellwig , Al Viro , Stefan Bader , linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/2] /proc/stat vs. failed order-4 allocation Message-Id: <20140618142931.857d57fe0007a361404f6cab@linux-foundation.org> In-Reply-To: <1402909492-36486-1-git-send-email-heiko.carstens@de.ibm.com> References: <1402909492-36486-1-git-send-email-heiko.carstens@de.ibm.com> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 16 Jun 2014 11:04:50 +0200 Heiko Carstens wrote: > These two patches are supposed to "fix" failed order-4 memory > allocations which have been observed when reading /proc/stat. > The problem has been observed on s390 as well as on x86. > > To address the problem change the seq_file memory allocations to > fallback to use vmalloc, so that allocations also work if memory > is fragmented. > > This approach seems to be simpler and less intrusive than changing > /proc/stat to use an interator. Also it "fixes" other users as well, > which use seq_file's single_open() interface. Yes, those changes look pretty simple and effective. I'm unclear on how urgent these fixes are. I semi-randomly tagged them for 3.16 with a -stable backport, but that could be changed?