From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752844AbdK3Mz2 (ORCPT ); Thu, 30 Nov 2017 07:55:28 -0500 Received: from www84.your-server.de ([213.133.104.84]:40686 "EHLO www84.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751443AbdK3Mz0 (ORCPT ); Thu, 30 Nov 2017 07:55:26 -0500 X-Greylist: delayed 1270 seconds by postgrey-1.27 at vger.kernel.org; Thu, 30 Nov 2017 07:55:26 EST Message-ID: <1512045250.2568.1.camel@seibold.net> Subject: Re: [PATCH v3 26/26] kfifo: DECLARE_KIFO_PTR(fifo, u64) does not work on arm 32 bit From: Stefani Seibold To: Mauro Carvalho Chehab , Sean Young , Andrew Morton Cc: linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, Randy Dunlap Date: Thu, 30 Nov 2017 13:34:10 +0100 In-Reply-To: <20171130102946.7168e93c@vento.lan> References: <1507622382.6064.2.camel@seibold.net> <20171130102946.7168e93c@vento.lan> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.24.5 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-Authenticated-Sender: stefani@seibold.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2017-11-30 at 10:29 -0200, Mauro Carvalho Chehab wrote: > Em Tue, 10 Oct 2017 09:59:42 +0200 > Sean Young escreveu: > > > If you try to store u64 in a kfifo (or a struct with u64 members), > > then the buf member of __STRUCT_KFIFO_PTR will cause 4 bytes > > padding due to alignment (note that struct __kfifo is 20 bytes > > on 32 bit). > > > > That in turn causes the __is_kfifo_ptr() to fail, which is caught > > by kfifo_alloc(), which now returns EINVAL. > > > > So, ensure that __is_kfifo_ptr() compares to the right structure. > > > > Signed-off-by: Sean Young > > Acked-by: Stefani Seibold > > Hi Stefani/Andrew, > > As this patch is required for the LIRC rework, would be ok if I would > merge it via the media tree? > It is okay by me. But the question remains why this patch wasn't already merged? Andrew: Any objections against this patch? > > > > --- > > include/linux/kfifo.h | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h > > index 41eb6fdf87a8..86b5fb08e96c 100644 > > --- a/include/linux/kfifo.h > > +++ b/include/linux/kfifo.h > > @@ -113,7 +113,8 @@ struct kfifo_rec_ptr_2 > > __STRUCT_KFIFO_PTR(unsigned char, 2, void); > > * array is a part of the structure and the fifo type where the > > array is > > * outside of the fifo structure. > > */ > > -#define __is_kfifo_ptr(fifo) (sizeof(*fifo) == > > sizeof(struct __kfifo)) > > +#define __is_kfifo_ptr(fifo) \ > > + (sizeof(*fifo) == sizeof(STRUCT_KFIFO_PTR(typeof(*(fifo)- > > >type)))) > > > > /** > > * DECLARE_KFIFO_PTR - macro to declare a fifo pointer object > > > > Thanks, > Mauro