From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 1B6758D0048 for ; Tue, 1 Feb 2011 12:58:07 -0500 (EST) Message-ID: <4D48498A.9040606@redhat.com> Date: Tue, 01 Feb 2011 12:57:30 -0500 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH] mlock: operate on any regions with protection != PROT_NONE References: <20110201010341.GA21676@google.com> In-Reply-To: <20110201010341.GA21676@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Michel Lespinasse Cc: linux-mm@kvack.org, Andrew Morton , Linus Torvalds , Tao Ma , KOSAKI Motohiro , Hugh Dickins List-ID: On 01/31/2011 08:03 PM, Michel Lespinasse wrote: > As Tao Ma noticed, change 5ecfda0 breaks blktrace. This is because > blktrace mmaps a file with PROT_WRITE permissions but without PROT_READ, > so my attempt to not unnecessarity break COW during mlock ended up > causing mlock to fail with a permission problem. > > I am proposing to let mlock ignore vma protection in all cases except > PROT_NONE. In particular, mlock should not fail for PROT_WRITE regions > (as in the blktrace case, which broke at 5ecfda0) or for PROT_EXEC > regions (which seem to me like they were always broken). > > Please review. I am proposing this as a candidate for 2.6.38 inclusion, > because of the behavior change with blktrace. Acked-by: Rik van Riel -- All rights reversed -- 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/ . Fight unfair telecom policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org