Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755568Ab1FTS5b (ORCPT ); Mon, 20 Jun 2011 14:57:31 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:56093 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755332Ab1FTS5a (ORCPT ); Mon, 20 Jun 2011 14:57:30 -0400 Date: Mon, 20 Jun 2011 14:57:29 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Alexander Holler cc: Nicolas Pitre , Arnd Bergmann , , , , lkml , Rabin Vincent Subject: Re: [PATCH] USB: ehci: use packed,aligned(4) instead of removing the packed attribute In-Reply-To: <4DFF9568.8030704@ahsoftware.de> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1108 Lines: 31 On Mon, 20 Jun 2011, Alexander Holler wrote: > Am 20.06.2011 20:39, schrieb Alan Stern: > > On Mon, 20 Jun 2011, Alexander Holler wrote: > > > >> I see it that way: packed is needed to be sure that at least for struct > >> ehci_regs there are no padding bytes inbetween the members. > > > > But is it _really_ needed? > > > >> It might > >> work without, but that depends on the compiler (-version, architecture, > >> whatever). > > > > Have there _ever_ been _any_ combinations of compiler, version, > > architecture, whatever, that had unwanted padding bytes in this > > structure? > > I don't know. But if there would be no doubts, this discussion would not > happen and I assume there never would have been an attribute packed there. Don't be so sure. That is very old code; the attribute could easily have been present for no good reason. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/