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 EF35C6B01AD for ; Tue, 25 May 2010 18:13:49 -0400 (EDT) Message-ID: <4BFC4B9D.1080902@yahoo.es> Date: Wed, 26 May 2010 00:13:49 +0200 From: Albert Herranz MIME-Version: 1.0 Subject: Re: [Bulk] Re: page_mkwrite vs pte dirty race in fb_defio References: <20100525160149.GE20853@laptop> <4BFC1657.5000707@yahoo.es> <20100525184700.GJ20853@laptop> In-Reply-To: <20100525184700.GJ20853@laptop> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Nick Piggin Cc: aya Kumar , Andrew Morton , Linus Torvalds , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org List-ID: On 05/25/2010 08:47 PM, Nick Piggin wrote: >>> I hope that should provide a more elegant solution to your problem. I >>> would really like you to take a look at that, because we already have >>> filesystem code (NFS) relying on it, and more code we have relying on >>> this synchronization, the more chance we would find a subtle problem >>> with it (also it should be just nicer). >> >> So if I undestand it correctly, using the "new" calling convention I should just lock the page on fb_deferred_io_mkwrite() and return VM_FAULT_LOCKED to fix the described race for fb_defio. > > As far as I can see from quick reading of the fb_defio code, yes > that should solve it (provided you lock the page inside the mutex, > of course). > Ok, thanks. I'm posting a new version as RFT. Cheers, Albert -- 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