From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20142C4360F for ; Fri, 1 Mar 2019 15:26:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB4262085A for ; Fri, 1 Mar 2019 15:26:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388764AbfCAP0T (ORCPT ); Fri, 1 Mar 2019 10:26:19 -0500 Received: from mx2.suse.de ([195.135.220.15]:43378 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726067AbfCAP0S (ORCPT ); Fri, 1 Mar 2019 10:26:18 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 22603AB4D; Fri, 1 Mar 2019 15:26:17 +0000 (UTC) Date: Fri, 1 Mar 2019 16:25:48 +0100 From: Cyril Hrubis To: Vlastimil Babka Cc: Oscar Salvador , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org, hughd@google.com, kirill@shutemov.name, joel@joelfernandes.org, jglisse@redhat.com, yang.shi@linux.alibaba.com, mgorman@techsingularity.net Subject: Re: [PATCH] mm,mremap: Bail out earlier in mremap_to under map pressure Message-ID: <20190301152547.GA25732@rei> References: <20190226091314.18446-1-osalvador@suse.de> <20190226140428.3e7c8188eda6a54f9da08c43@linux-foundation.org> <20190227213205.5wdjucqdgfqx33tr@d104.suse.de> <5edcfeb8-4f53-0fe6-1e5b-c1e485f91d0d@suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5edcfeb8-4f53-0fe6-1e5b-c1e485f91d0d@suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi! > Hopefully the only program that would start failing would be a LTP test > testing the current behavior near the limit (if such test exists). And > that can be adjusted. There does not seem to be a mremap() test that would do such a thing, so we should be safe :-). BTW there was a similar fix for mmap() with MAP_FIXED that caused a LTP test to fail and was fixed in: commit e8420a8ece80b3fe810415ecf061d54ca7fab266 Author: Cyril Hrubis Date: Mon Apr 29 15:08:33 2013 -0700 mm/mmap: check for RLIMIT_AS before unmapping And I haven't heard of any breakages so far so I guess that this very similar situation and that the possibility of breaking real world applications here is really low. -- Cyril Hrubis chrubis@suse.cz