From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 96628C35242 for ; Sat, 8 Feb 2020 20:18:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6F7EE21741 for ; Sat, 8 Feb 2020 20:18:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727507AbgBHUSh (ORCPT ); Sat, 8 Feb 2020 15:18:37 -0500 Received: from smtprelay0152.hostedemail.com ([216.40.44.152]:43861 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727471AbgBHUSh (ORCPT ); Sat, 8 Feb 2020 15:18:37 -0500 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay07.hostedemail.com (Postfix) with ESMTP id 675AE181D3026; Sat, 8 Feb 2020 20:18:35 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: sort14_109d5eb21af35 X-Filterd-Recvd-Size: 2794 Received: from XPS-9350.home (unknown [47.151.143.254]) (Authenticated sender: joe@perches.com) by omf05.hostedemail.com (Postfix) with ESMTPA; Sat, 8 Feb 2020 20:18:34 +0000 (UTC) Message-ID: Subject: Re: [PATCH] s390/kaslr: Fix casts in get_random From: Joe Perches To: Nathan Chancellor , Heiko Carstens , Vasily Gorbik , Christian Borntraeger Cc: linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com Date: Sat, 08 Feb 2020 12:17:20 -0800 In-Reply-To: <20200208141052.48476-1-natechancellor@gmail.com> References: <20200208141052.48476-1-natechancellor@gmail.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.34.1-2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2020-02-08 at 07:10 -0700, Nathan Chancellor wrote: > Clang warns: > > ../arch/s390/boot/kaslr.c:78:25: warning: passing 'char *' to parameter > of type 'const u8 *' (aka 'const unsigned char *') converts between > pointers to integer > types with different sign [-Wpointer-sign] > (char *) entropy, (char *) entropy, > ^~~~~~~~~~~~~~~~ > ../arch/s390/include/asm/cpacf.h:280:28: note: passing argument to > parameter 'src' here > u8 *dest, const u8 *src, long src_len) > ^ > 2 warnings generated. > > Fix the cast to match what else is done in this function. > > Fixes: b2d24b97b2a9 ("s390/kernel: add support for kernel address space layout randomization (KASLR)") > Link: https://github.com/ClangBuiltLinux/linux/issues/862 > Signed-off-by: Nathan Chancellor > --- > arch/s390/boot/kaslr.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/s390/boot/kaslr.c b/arch/s390/boot/kaslr.c > index 5d12352545c5..5591243d673e 100644 > --- a/arch/s390/boot/kaslr.c > +++ b/arch/s390/boot/kaslr.c > @@ -75,7 +75,7 @@ static unsigned long get_random(unsigned long limit) > *(unsigned long *) prng.parm_block ^= seed; > for (i = 0; i < 16; i++) { > cpacf_kmc(CPACF_KMC_PRNG, prng.parm_block, > - (char *) entropy, (char *) entropy, > + (u8 *) entropy, (u8 *) entropy, Why not change the function to take void *? static inline int cpacf_kmc(unsigned long func, void *param, u8 *dest, const u8 *src, long src_len) vs: static inline int cpacf_kmc(unsigned long func, void *param, void *dest, const void *src, long src_len) and remove the casts?