From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 690F36B009C for ; Fri, 17 Dec 2010 10:34:07 -0500 (EST) Received: by iyj17 with SMTP id 17so508350iyj.14 for ; Fri, 17 Dec 2010 07:34:04 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20101217112111.GA8323@localhost> References: <20101213144646.341970461@intel.com> <20101213150329.002158963@intel.com> <20101217021934.GA9525@localhost> <20101217112111.GA8323@localhost> Date: Sat, 18 Dec 2010 00:34:04 +0900 Message-ID: Subject: Re: [PATCH] writeback: skip balance_dirty_pages() for in-memory fs From: Minchan Kim Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Sender: owner-linux-mm@kvack.org To: Wu Fengguang Cc: Hugh Dickins , Andrew Morton , Jan Kara , Christoph Hellwig , Trond Myklebust , Dave Chinner , Theodore Ts'o , Chris Mason , Peter Zijlstra , Mel Gorman , Rik van Riel , KOSAKI Motohiro , Greg Thelen , linux-mm , "linux-fsdevel@vger.kernel.org" , LKML List-ID: On Fri, Dec 17, 2010 at 8:21 PM, Wu Fengguang wrot= e: > This avoids unnecessary checks and dirty throttling on tmpfs/ramfs. > > It also prevents > > [ =A0388.126563] BUG: unable to handle kernel NULL pointer dereference at= 0000000000000050 > > in the balance_dirty_pages tracepoint, which will call > > =A0 =A0 =A0 =A0dev_name(mapping->backing_dev_info->dev) > > but shmem_backing_dev_info.dev is NULL. > > CC: Hugh Dickins > Signed-off-by: Wu Fengguang Reviewed-by: Minchan Kim Is it a material for -stable? --=20 Kind regards, Minchan Kim -- 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