From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752758AbdIESSP (ORCPT ); Tue, 5 Sep 2017 14:18:15 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:33028 "EHLO prv3-mh.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752064AbdIESSO (ORCPT ); Tue, 5 Sep 2017 14:18:14 -0400 Message-ID: <1504635482.4516.3.camel@suse.com> Subject: Re: [PATCH v4 2/3] string.h: add memcpy_and_pad() From: Martin Wilck To: Arnd Bergmann Cc: Christoph Hellwig , Keith Busch , Sagi Grimberg , Johannes Thumshirn , Hannes Reinecke , linux-nvme@lists.infradead.org, Linux Kernel Mailing List Date: Tue, 05 Sep 2017 20:18:02 +0200 In-Reply-To: References: <20170810084541.bawqaebfycnguomx@infradead.org> <20170814201239.15255-1-mwilck@suse.com> <20170814201239.15255-3-mwilck@suse.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.24.4 Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2017-09-05 at 09:28 +0200, Arnd Bergmann wrote: > > > +/** > > + * memcpy_and_pad - Copy one buffer to another with padding > > + * @dest: Where to copy to > > + * @dest_len: The destination buffer size > > + * @src: Where to copy from > > + * @count: The number of bytes to copy > > + * @pad: Character to use for padding if space is left in > > destination. > > + */ > > +__FORTIFY_INLINE void memcpy_and_pad(void *dest, size_t dest_len, > > + const void *src, size_t count, > > int pad) > > +{ > > This is causing compile-time warnings for me: > > In file included from /git/arm-soc/arch/x86/include/asm/string.h:2:0, > from /git/arm-soc/include/linux/string.h:18, > from /git/arm-soc/arch/x86/include/asm/page_32.h:34, > from /git/arm-soc/arch/x86/include/asm/page.h:13, > from /git/arm- > soc/arch/x86/include/asm/thread_info.h:11, > from /git/arm-soc/include/linux/thread_info.h:37, > from /git/arm-soc/arch/x86/include/asm/preempt.h:6, > from /git/arm-soc/include/linux/preempt.h:80, > from /git/arm-soc/include/linux/spinlock.h:50, > from /git/arm-soc/include/linux/seqlock.h:35, > from /git/arm-soc/include/linux/time.h:5, > from /git/arm-soc/include/linux/stat.h:18, > from /git/arm-soc/include/linux/module.h:10, > from /git/arm-soc/drivers/md/dm-integrity.c:9: > /git/arm-soc/arch/x86/include/asm/string_32.h:196:25: error: > '__memcpy' is static but used in inline function 'memcpy_and_pad' > which is not static [-Werror] > #define memcpy(t, f, n) __memcpy((t), (f), (n)) > ^~~~~~~~ > /git/arm-soc/include/linux/string.h:466:3: note: in expansion of > macro 'memcpy' > > ^ > /git/arm-soc/arch/x86/include/asm/string_32.h:196:25: error: > '__memcpy' is static but used in inline function 'memcpy_and_pad' > which is not static [-Werror] > #define memcpy(t, f, n) __memcpy((t), (f), (n)) > ^~~~~~~~ > > The problem is the use of __FORTIFY_INLINE outside of the #ifdef > section above it. > I used an ugly local workaround, duplicating the function with a > 'static inline' variant > in an #else block. Alternatively we could add an extern version in > lib/string.c for the > non-fortified case. I'm sorry. It seems that I messed the code up by trying to do it right. I suggest to simply drop the fortification code from this function, which is not a "common str/mem function" anyway. Please tell me if that'd be ok for you. I'll send a patch in a follow-up email. Martin -- Dr. Martin Wilck , Tel. +49 (0)911 74053 2107 SUSE Linux GmbH, GF: Felix Imendörffer, Jane Smithard, Graham Norton HRB 21284 (AG Nürnberg)