From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S969367AbdDSUs4 (ORCPT ); Wed, 19 Apr 2017 16:48:56 -0400 Received: from mail-yw0-f193.google.com ([209.85.161.193]:35809 "EHLO mail-yw0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S966490AbdDSUsy (ORCPT ); Wed, 19 Apr 2017 16:48:54 -0400 MIME-Version: 1.0 In-Reply-To: <20170419181412.GF128305@google.com> References: <20170404180720.182336-1-mka@chromium.org> <20170419181412.GF128305@google.com> From: Arnd Bergmann Date: Wed, 19 Apr 2017 22:48:47 +0200 X-Google-Sender-Auth: 9La_fWKLy1mThvNr3e7KiWSbqXo Message-ID: Subject: Re: [PATCH] fs: compat: Remove warning from COMPATIBLE_IOCTL To: Matthias Kaehlcke Cc: Alexander Viro , Mark Charlebois , Behan Webster , Linux Kernel Mailing List , Linux FS-devel Mailing List , Grant Grundler , Michael Davidson , Greg Hackmann , Peter Foley Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 19, 2017 at 8:14 PM, Matthias Kaehlcke wrote: > El Tue, Apr 04, 2017 at 11:07:20AM -0700 Matthias Kaehlcke ha dit: > >> From: Mark Charlebois >> >> cmd in COMPATIBLE_IOCTL is always a u32, so cast it so there isn't a >> warning about an overflow in XFORM. >> >> From: Mark Charlebois >> Signed-off-by: Mark Charlebois >> Signed-off-by: Behan Webster >> Signed-off-by: Matthias Kaehlcke >> Acked-by: Arnd Bergmann >> --- >> Resending https://patchwork.kernel.org/patch/4961631/ The patch looks correct to me, Acked-by: Arnd Bergmann >> fs/compat_ioctl.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c >> index 11d087b2b28e..6116d5275a3e 100644 >> --- a/fs/compat_ioctl.c >> +++ b/fs/compat_ioctl.c >> @@ -833,7 +833,7 @@ static int compat_ioctl_preallocate(struct file *file, >> */ >> #define XFORM(i) (((i) ^ ((i) << 27) ^ ((i) << 17)) & 0xffffffff) >> >> -#define COMPATIBLE_IOCTL(cmd) XFORM(cmd), >> +#define COMPATIBLE_IOCTL(cmd) XFORM((u32)cmd), >> /* ioctl should not be warned about even if it's not implemented. >> Valid reasons to use this: >> - It is implemented with ->compat_ioctl on some device, but programs > > Ping, any feedback on this change? One minor comment on the patch: when you address a warning in a patch, it helps to put the compiler warning output into the changelog. Aside from that, I see that you are upstreaming a number of clang related patches. I actually have a longer series of clang patches that I took from llvmlinux and hacked up to the point where I could build ARM randconfig kernels without any warnings or errors. If you are interested, I can separate the clang patches from my normal randconfig build tree and upload the git tree for you to look at and cherry-pick further patches. Arnd