From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758441Ab2JKKYe (ORCPT ); Thu, 11 Oct 2012 06:24:34 -0400 Received: from bedivere.hansenpartnership.com ([66.63.167.143]:36170 "EHLO bedivere.hansenpartnership.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755258Ab2JKKYc (ORCPT ); Thu, 11 Oct 2012 06:24:32 -0400 Message-ID: <1349951069.2425.44.camel@dabdike.int.hansenpartnership.com> Subject: Re: [RESEND PATCH] scsi: make struct scsi_varlen_cdb_hdr packed From: James Bottomley To: James Hogan Cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org Date: Thu, 11 Oct 2012 11:24:29 +0100 In-Reply-To: <1349946933-30314-1-git-send-email-james.hogan@imgtec.com> References: <1349946933-30314-1-git-send-email-james.hogan@imgtec.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.4.4 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2012-10-11 at 10:15 +0100, James Hogan wrote: > The struct scsi_varlen_cdb_hdr is expected to be exactly 10 bytes when > used in struct osd_cdb_head, but it isn't marked as packed. Some > architectures will round the struct size up which triggers BUILD_BUG_ON > compile errors in osd_initiator.c when the outer structs are unexpected > sizes. This is fixed by marking struct scsi_varlen_cdb_hdr as __packed. What actual problem have you encountered? The structure is {u8[8], u16} which is naturally packed on every architecture I know about. I've even built osd_initiator without problem on parisc, which has some of the most rigid alignment rules I've seen. James