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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6AD21C98318 for ; Sat, 26 Sep 2026 09:40:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Type:MIME-Version: Message-ID:Date:References:In-Reply-To:Subject:Cc:To:From:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KhakconhrGu2oZYTr+VE77hBjiLRqXZ4OFKpCDCtIwM=; b=z0djSebuZYteI5V7MH7izC2K+9 3/rrUlX5Bg3TNr3R/K0L0zGiOKfFOxPrpdHvXZQ/MBAtycuvMvGJ5koguUfCy0PXjZ6Kdi2d5sjvk +7b9zbZKhKRTmIlESalFj7zStNbF5GsKlqIjriKvsJaP7PIhRM4diyXPr6JWGPtPXteK6vsjNAiFo cdf2TBQ+f/bXDWKKfmdirwdii556R5uh7ToRP8tsY8yKY4r+AerChAYt2Pmh1o4Y1saD2086zuqJc hYX6Y3dSr6JASLvf3qEK0hzLxzvO0yKLvGWSleSON9z2mP0QzBGIrgmdCEuvtk4mcH4OZSq3jkaxQ dBVtOmrg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xAOt6-0000000FDsD-0nmQ; Sat, 26 Sep 2026 09:40:08 +0000 Received: from mail-out.m-online.net ([212.18.0.10]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xAOt3-0000000FDqi-0bt3; Sat, 26 Sep 2026 09:40:07 +0000 Received: from mail-out.m-online.net (mail-out.m-online.net [212.18.0.10]) by mail-out.m-online.net (Postfix) with ESMTP id 4hsMx95lHWz1sPSD; Sat, 26 Sep 2026 11:39:57 +0200 (CEST) Received: from frontend03.mail.m-online.net (unknown [192.168.6.182]) by mail-out.m-online.net (Postfix) with ESMTP id 4hsMx35nYKz1sPRy; Sat, 26 Sep 2026 11:39:51 +0200 (CEST) Received: from localhost (dynscan3.mnet-online.de [192.168.6.87]) by mail.m-online.net (Postfix) with ESMTP id 4hsMx319yNz1qqlR; Sat, 26 Sep 2026 11:39:51 +0200 (CEST) X-Virus-Scanned: amavis at mnet-online.de Received: from mail.mnet-online.de ([192.168.6.182]) by localhost (dynscan3.mail.m-online.net [192.168.6.87]) (amavis, port 10024) with ESMTP id r0-zxGatOHrc; Sat, 26 Sep 2026 11:39:43 +0200 (CEST) X-Auth-Info: wFe88JiXbDxEAWB88fOER1RGk4p+sTXtzQeYAh7Q9amIwrx952rztx0YkIPQk3RO Received: from tiger (aftr-82-135-83-101.dynamic.mnet-online.de [82.135.83.101]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mail.mnet-online.de (Postfix) with ESMTPSA; Sat, 26 Sep 2026 11:39:43 +0200 (CEST) From: Andreas Schwab To: Nathan Chancellor Cc: Andy Lutomirski , Thomas Gleixner , Theodore Ts'o , "Jason A. Donenfeld" , Vincenzo Frascino , Nick Desaulniers , Bill Wendling , Justin Stitt , Catalin Marinas , Will Deacon , Mark Rutland , Huacai Chen , WANG Xuerui , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , "Christophe Leroy (CS GROUP)" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, llvm@lists.linux.dev Subject: Re: [PATCH v2] random: vDSO: Avoid call to memset() when zeroing reserved in __cvdso_getrandom_data() In-Reply-To: <20260925-vdso-getrandom-avoid-memset-llvm-24-v2-1-ce640f872393@kernel.org> References: <20260925-vdso-getrandom-avoid-memset-llvm-24-v2-1-ce640f872393@kernel.org> Date: Sat, 26 Sep 2026 11:39:43 +0200 Message-ID: <87zex4ic68.fsf@linux-m68k.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260926_024005_337116_99B29611 X-CRM114-Status: GOOD ( 10.07 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sep 25 2026, Nathan Chancellor wrote: > +#if __has_builtin(__builtin_memset_inline) > +#define memset_inline(dst, value, size) __builtin_memset_inline(dst, value, size) > +#elif IS_ENABLED(CONFIG_CC_HAS_OPT_INLINE_MEMSET) > +#define memset_inline(dst, value, size) __builtin_memset(dst, value, size) > +#else > +static inline void *memset_inline(void *dst, int value, size_t size) > +{ > + char *d = dst; > + > + while (size--) > + *d++ = value; > + > + return d; > +} > +#endif > + memset actually returns the original pointer, not the incremented one. Nothing uses the return value of memset_inline here, but it is confusing. -- Andreas Schwab, schwab@linux-m68k.org GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1 "And now for something completely different."