Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756515Ab3IMPGX (ORCPT ); Fri, 13 Sep 2013 11:06:23 -0400 Received: from mail-wi0-f176.google.com ([209.85.212.176]:42809 "EHLO mail-wi0-f176.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755910Ab3IMPGV (ORCPT ); Fri, 13 Sep 2013 11:06:21 -0400 MIME-Version: 1.0 In-Reply-To: <20130913121529.GA1437@flint.arm.linux.org.uk> References: <20130912153629.16487.88969@localhost.localdomain> <20130913121529.GA1437@flint.arm.linux.org.uk> Date: Fri, 13 Sep 2013 11:06:20 -0400 Message-ID: Subject: Re: [GIT PULL] Btrfs From: Josh Boyer To: Geert Uytterhoeven , Chris Mason , Mark Fasheh , Linus Torvalds , linux-btrfs , "Linux-Kernel@Vger. Kernel. Org" , Linux-Arch Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1464 Lines: 34 On Fri, Sep 13, 2013 at 8:15 AM, Russell King wrote: > On Fri, Sep 13, 2013 at 07:53:21AM -0400, Josh Boyer wrote: >> I'm not an ARM expert, so I don't know if ARM should use the >> asm-generic implementations, or just use __get_user/__put_user in all >> cases. I've CC'd rmk. > > Why do we have uaccess-unaligned.h ? Normally, these kinds of things > are spawned by architectures which have problems with unaligned accesses, > ARM being one of them, but afaik we've never need this. > > With the kernel-side trapping of unaligned accesses on older hardware, > we've always dealt with the normal accessor faulting. > > From what I can tell in the git history, these unaligned put_user and > get_user have existed all the way back to the dawn of git use. > > Can someone enlighten me why we have them? So while that gets sorted out, would it be safe to just do as Geert did on m68k and put: #define __put_user_unaligned(x, ptr) __put_user((x), (ptr)) in arch/arm/include/asm/uaccess.h, and let the normal accessors and kernel-side trapping deal with things? I'm thinking that's a local fix until something gets sorted upstream, but I don't want to do it if it's going to break things. josh -- 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/