From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752227Ab3KRTa5 (ORCPT ); Mon, 18 Nov 2013 14:30:57 -0500 Received: from merlin.infradead.org ([205.233.59.134]:49580 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751420Ab3KRTa4 (ORCPT ); Mon, 18 Nov 2013 14:30:56 -0500 Message-ID: <528A6AD4.7080702@kernel.dk> Date: Mon, 18 Nov 2013 12:30:28 -0700 From: Jens Axboe User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Akinobu Mita , linux-kernel@vger.kernel.org, akpm@linux-foundation.org CC: Alexander Viro Subject: Re: [PATCH] bio: fix argument of __bio_add_page() for max_sectors > 0xffff References: <1384780302-25009-1-git-send-email-akinobu.mita@gmail.com> In-Reply-To: <1384780302-25009-1-git-send-email-akinobu.mita@gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/18/2013 06:11 AM, Akinobu Mita wrote: > The data type of max_sectors and max_hw_sectors in queue settings are > unsigned int. But these values are passed to __bio_add_page() as an > argument whose data type is unsigned short. In the worst case such as > max_sectors is 0x10000, bio_add_page() can't add a page and IOs can't > proceed. Thanks, added. Even at 512b sectors, 0xffff sectors would be a huuuuge page. So I don't think we'd ever see this bug hit, iirc huge pages are still broken down for IO. But it's better to be safe... -- Jens Axboe