From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751292AbaIJMYv (ORCPT ); Wed, 10 Sep 2014 08:24:51 -0400 Received: from relay.parallels.com ([195.214.232.42]:40000 "EHLO relay.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750925AbaIJMYu (ORCPT ); Wed, 10 Sep 2014 08:24:50 -0400 Message-ID: <5410430E.5030804@parallels.com> Date: Wed, 10 Sep 2014 16:24:46 +0400 From: Maxim Patlasov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Miklos Szeredi CC: , , , , , Subject: Re: [PATCH 0/2] fuse: fix regression in fuse_get_user_pages() References: <20140903100826.23218.95122.stgit@localhost.localdomain> <20140910095115.GA7441@tucsk.piliscsaba.szeredi.hu> In-Reply-To: <20140910095115.GA7441@tucsk.piliscsaba.szeredi.hu> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.30.22.200] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/10/2014 01:51 PM, Miklos Szeredi wrote: > On Wed, Sep 03, 2014 at 02:10:23PM +0400, Maxim Patlasov wrote: >> Hi, >> >> The patchset fixes a regression introduced by the following commits: >> >> c7f3888ad7f0 ("switch iov_iter_get_pages() to passing maximal number of pages") >> c9c37e2e6378 ("fuse: switch to iov_iter_get_pages()") >> > Hmm, instead of reverting to passing maxbytes *instead* of maxpages, I think the > right fix is to *add* the maxbytes argument. > > Just maxbytes alone doesn't have enough information in it. E.g. 4096 contiguous > bytes could occupy 1 or 2 pages, depending on the starting offset. Yes, you are right. I missed that c7f3888ad7f0 fixed a subtle bug in get_pages_iovec(). > > So how about the following (untested) patch? Your patch works fine in my tests. Thanks, Maxim