Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261733AbTI3WDu (ORCPT ); Tue, 30 Sep 2003 18:03:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261750AbTI3WDt (ORCPT ); Tue, 30 Sep 2003 18:03:49 -0400 Received: from fw.osdl.org ([65.172.181.6]:14546 "EHLO mail.osdl.org") by vger.kernel.org with ESMTP id S261733AbTI3WDr (ORCPT ); Tue, 30 Sep 2003 18:03:47 -0400 Date: Tue, 30 Sep 2003 14:43:13 -0700 From: Andrew Morton To: Russell King Cc: arun.sharma@intel.com, linux-kernel@vger.kernel.org, kevin.tian@intel.com, willy@debian.org Subject: Re: [PATCH] incorrect use of sizeof() in ioctl definitions Message-Id: <20030930144313.601a4655.akpm@osdl.org> In-Reply-To: <20030930223531.B10154@flint.arm.linux.org.uk> References: <3F79ED60.2030207@intel.com> <20030930140805.0e3158e7.akpm@osdl.org> <20030930223531.B10154@flint.arm.linux.org.uk> X-Mailer: Sylpheed version 0.9.4 (GTK+ 1.2.10; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Russell King wrote: > > > /* out param: u32* backlight value: 0 to 15 */ > > -#define FBIO_ATY128_GET_MIRROR _IOR('@', 1, sizeof(__u32*)) > > +#define FBIO_ATY128_GET_MIRROR _IOR('@', 1, __u32*) > > /* in param: u32* backlight value: 0 to 15 */ > > -#define FBIO_ATY128_SET_MIRROR _IOW('@', 2, sizeof(__u32*)) > > +#define FBIO_ATY128_SET_MIRROR _IOW('@', 2, __u32*) > > > > static int aty128fb_ioctl(struct inode *inode, struct file *file, u_int cmd, > > u_long arg, struct fb_info *info) > > > > > > Matthew's conversion mainly converted things to size_t, but from the looks > > of it, __u32* is the right thing to use in this case, I think? > > sizeof(__u32*) may not be sizeof(sizeof(__u32*)), so this would be an API > change... Therefore, all these wrong entries need to change to size_t > (preferably with the real type following inside a comment so we don't > loose useful information.) In that case I'm going to need a bit of education as to what the whole thing is trying to do. If FBIO_ATY128_SET_MIRROR is really supposed to be passing a pointer into the ioctl then we *want* the encoded ioctl number to be different for 32-bit-compiled userspace and 64-bit-compiled userspace, don't we? - 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/