From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pa0-f71.google.com (mail-pa0-f71.google.com [209.85.220.71]) by kanga.kvack.org (Postfix) with ESMTP id 2E3606B0005 for ; Thu, 12 May 2016 07:49:53 -0400 (EDT) Received: by mail-pa0-f71.google.com with SMTP id gw7so102420001pac.0 for ; Thu, 12 May 2016 04:49:53 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org. [2001:1868:205::9]) by mx.google.com with ESMTPS id c68si17056030pfd.116.2016.05.12.04.49.52 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 12 May 2016 04:49:52 -0700 (PDT) Date: Thu, 12 May 2016 04:49:48 -0700 From: Christoph Hellwig Subject: Re: UBIFS and page migration (take 3) Message-ID: <20160512114948.GA25113@infradead.org> References: <1462974823-3168-1-git-send-email-richard@nod.at> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1462974823-3168-1-git-send-email-richard@nod.at> Sender: owner-linux-mm@kvack.org List-ID: To: Richard Weinberger Cc: linux-fsdevel@vger.kernel.org, linux-mtd@lists.infradead.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, boris.brezillon@free-electrons.com, maxime.ripard@free-electrons.com, david@sigma-star.at, david@fromorbit.com, dedekind1@gmail.com, alex@nextthing.co, akpm@linux-foundation.org, sasha.levin@oracle.com, iamjoonsoo.kim@lge.com, rvaswani@codeaurora.org, tony.luck@intel.com, shailendra.capricorn@gmail.com, kirill.shutemov@linux.intel.com, hch@infradead.org, hughd@google.com, mgorman@techsingularity.net, vbabka@suse.cz Hi Richard, the series looks fine to me, but it fails to address the root cause: that we have an inherently dangerous default for ->migratepage that assumes that file systems are implemented a certain way. I think the series should also grow a third patch to remove the default and just wire it up for the known good file systems, although we'd need some input on what known good is. Any idea what filesystems do get regular testing with code that's using CMA? A good approximation might be those that use the bufer_head based aops from fs/buffer.c -- 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