From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752705AbaLTGiF (ORCPT ); Sat, 20 Dec 2014 01:38:05 -0500 Received: from mail.eperm.de ([89.247.134.16]:55093 "EHLO mail.eperm.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751195AbaLTGiB convert rfc822-to-8bit (ORCPT ); Sat, 20 Dec 2014 01:38:01 -0500 X-AuthUser: sm@eperm.de From: Stephan Mueller To: leroy christophe Cc: Herbert Xu , linux-crypto , "'LKML'" Subject: Re: algif_hash: splice of data > 2**16 Date: Sat, 20 Dec 2014 07:37:55 +0100 Message-ID: <3364866.GGZiChayfE@tachyon.chronox.de> User-Agent: KMail/4.14.3 (Linux/3.17.6-300.fc21.x86_64; KDE/4.14.3; x86_64; ; ) In-Reply-To: <5492C6FC.50005@c-s.fr> References: <8707521.TbV00HIEUx@tauon> <5492C6FC.50005@c-s.fr> MIME-Version: 1.0 Content-Transfer-Encoding: 8BIT Content-Type: text/plain; charset="iso-8859-1" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am Donnerstag, 18. Dezember 2014, 13:22:20 schrieb leroy christophe: Hi Christophe, > Le 18/12/2014 13:15, Stephan Mueller a écrit : > > Hi Herbert, > > > > While testing the vmsplice/splice interface of algif_hash I was made > > aware of the problem that data blobs larger than 16 pages do not seem to > > be hashed properly. > > > > For testing, a file is mmap()ed and handed to vmsplice / splice. If the > > file is smaller than 2**16, the interface returns the proper hash. > > However, when the file is larger, only the first 2**16 bytes seem to be > > used. > > > > When adding printk's to hash_sendpage, I see that this function is > > invoked exactly 16 times where the first 15 invocations have the > > MSG_MORE flag set and the last invocation does not have MSG_MORE. > > Hi Stephan, > > I have already noticed the same issue and proposed a patch, but I never > got any feedback and it has never been merged, allthought I pinged it a > few times. > > See https://lkml.org/lkml/2014/4/18/276 After testing, this patch does not work for me. The operation still stops after 16 pages. > > Christophe -- Ciao Stephan