Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030925AbaLLRUS (ORCPT ); Fri, 12 Dec 2014 12:20:18 -0500 Received: from mail-qg0-f42.google.com ([209.85.192.42]:33599 "EHLO mail-qg0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030874AbaLLRUP convert rfc822-to-8bit (ORCPT ); Fri, 12 Dec 2014 12:20:15 -0500 MIME-Version: 1.0 In-Reply-To: <1415653764-22162-1-git-send-email-cernekee@gmail.com> References: <1415653764-22162-1-git-send-email-cernekee@gmail.com> From: Kevin Cernekee Date: Fri, 12 Dec 2014 09:19:54 -0800 Message-ID: Subject: Re: [PATCH 1/2] [CIFS] Fix signed/unsigned pointer warning To: sfrench@samba.org Cc: linux-cifs@vger.kernel.org, "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Nov 10, 2014 at 1:09 PM, Kevin Cernekee wrote: > Commit 2ae83bf93882d1 ("[CIFS] Fix setting time before epoch (negative > time values)") changed "u64 t" to "s64 t", which makes do_div() complain > about a pointer signedness mismatch: > > CC fs/cifs/netmisc.o > In file included from ./arch/mips/include/asm/div64.h:12:0, > from include/linux/kernel.h:124, > from include/linux/list.h:8, > from include/linux/wait.h:6, > from include/linux/net.h:23, > from fs/cifs/netmisc.c:25: > fs/cifs/netmisc.c: In function ‘cifs_NTtimeToUnix’: > include/asm-generic/div64.h:43:28: warning: comparison of distinct pointer types lacks a cast [enabled by default] > (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \ > ^ > fs/cifs/netmisc.c:941:22: note: in expansion of macro ‘do_div’ > ts.tv_nsec = (long)do_div(t, 10000000) * 100; > > Introduce a temporary "u64 abs_t" variable to fix this. > > Signed-off-by: Kevin Cernekee > --- > fs/cifs/netmisc.c | 12 +++++++----- > 1 file changed, 7 insertions(+), 5 deletions(-) > > > Note: this is compile-tested only (on a 32-bit build). > > > diff --git a/fs/cifs/netmisc.c b/fs/cifs/netmisc.c > index b333ff6..abae6dd 100644 > --- a/fs/cifs/netmisc.c > +++ b/fs/cifs/netmisc.c > @@ -926,6 +926,7 @@ cifs_NTtimeToUnix(__le64 ntutc) > > /* Subtract the NTFS time offset, then convert to 1s intervals. */ > s64 t = le64_to_cpu(ntutc) - NTFS_TIME_OFFSET; > + u64 abs_t; > > /* > * Unfortunately can not use normal 64 bit division on 32 bit arch, but > @@ -933,13 +934,14 @@ cifs_NTtimeToUnix(__le64 ntutc) > * to special case them > */ > if (t < 0) { > - t = -t; > - ts.tv_nsec = (long)(do_div(t, 10000000) * 100); > + abs_t = -t; > + ts.tv_nsec = (long)(do_div(abs_t, 10000000) * 100); > ts.tv_nsec = -ts.tv_nsec; > - ts.tv_sec = -t; > + ts.tv_sec = -abs_t; > } else { > - ts.tv_nsec = (long)do_div(t, 10000000) * 100; > - ts.tv_sec = t; > + abs_t = t; > + ts.tv_nsec = (long)do_div(abs_t, 10000000) * 100; > + ts.tv_sec = abs_t; > } > > return ts; > -- > 2.1.1 > Hi guys, I am still seeing this warning on Linus' head of tree. Do you think this is something we can pull in for 3.19? Thanks! -- 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/