From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=192.198.163.12 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794581074; b=lCXvx0BUXaSDyRX3gIsn4FgOdHH/TeVd3fNZM3EDD2ztBakQcr84p+St7bhd4Lioe30T 1xsnNIwicU5dv1zQuYbRnRS9+qzEOWA17gVHVWKjsGBqAvXtNQQnLH2koaGmfcze15gCS HztKQ3PZ1EgFn5aVnf0pE4QeHtGmfGj5o3nDP91voiVZcmbZ/+Z/SMY4zGIXrzslp8zAR b/R8xIpUxnKY9d6RpgBNycbDQWtuMgC9gzMNFXTjNv79Wyod0KADeKHBdRAM5DWEVGyPv 3UAaCzQvDR+23395yiRWG4mx7yKHohI7pVr3jqtL3uPKPaCpD3cYwVO7JYGgPlxlKyA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794581074; h=DMARC-Filter:DKIM-Signature:X-CSE-ConnectionGUID:X-CSE-MsgGUID: X-IronPort-AV:X-IronPort-AV:Received:X-CSE-ConnectionGUID: X-CSE-MsgGUID:X-ExtLoop1:X-IronPort-AV:Received:Date:From:To:Cc: Subject:Message-ID:References:MIME-Version:Content-Type: Content-Disposition:In-Reply-To:Organization; bh=PCohGcK4MbH0+m0C2E2oEI2m0dBP6JKw67OWX2Ixdd0=; b=Um1AvFkCDVvxPuHrHnA5cbLPevxgMLRed3+qaRGVitro1/fzYHmu2hOYxrYEdEYKYx8O qr7QCO1i4pqzrDNY0WWnSGkU7EsG/Sy5v6c5f5bNTTNAoznqZkO5oK5O29InYxQgDdV24 qCLspYENPSi5gk+FNinpdsXoWrrIb9zNKSBQqswk3hnctac4SKTfBXAicTSLKr/TdiTeW j4fy60QwnTeQZ3f7VQZ2k0iLTOPSGkfGQtr+xs7+3UnhI0hL/zBxzxs+3fRqxO9E8aWHc h2QbeozxJU8qUzTZaXGBXWMukZ0rBku7CNPJhQ6V1vOioCzb8+I2piQe5/6K1Vz7R/Q== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b="QR/RmCXl"; arc=none smtp.remote-ip=192.198.163.12 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) (using TLSv1.2 with cipher ECDHE-ECDSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EAA75606A331; Fri, 13 Nov 2026 14:44:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org EAA75606A331 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=QR/RmCXl DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1794581074; x=1826117074; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=DyI5H6asWxx+tH3VejHSQI8D30gWxhl9i+ORCFAvja8=; b=QR/RmCXlP7YeiKs4cIIQlvZUq5MI+AsMQylxmqVHyTMWw7lKwXW1Em/i C8Za6TM3AWBodCXFoxBGHaSr08gZDp/2T1d33OsWoROoCgSzoPvIyAKgL CKrY8ijrn5JUUe8Z3GKLModbDij415qNKB25Fy89aNmCaeMlcfguqUR7h NYkRZ6mO+oCr5Kdd+CHSY9nDKc/X6Cb45xQTBkQvVYxQFzmyNBXJLeWr5 mSg01d6+9adGLilgryjfjXeZ5B43nnxQ5S4uwQTqtkv4pi/ChTIU6We76 s4RzzQE1maf4u0JUvpoxQhZK0K+cEVM8ZKkIG5WsXfTa1ZVN5prPz1YEZ g==; X-CSE-ConnectionGUID: CTgI1O+eQmaJNplK+6hInw== X-CSE-MsgGUID: Z2Dq5KRQQLavbU3FEw0CpA== X-IronPort-AV: E=McAfee;i="6800,10657,11965"; a="3288677" X-IronPort-AV: E=Sophos;i="6.27,211,1787036400"; d="scan'208";a="3288677" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Nov 2026 06:44:18 -0800 X-CSE-ConnectionGUID: rwx0kEqrS7KcRwQIohl0qQ== X-CSE-MsgGUID: TsUR/GvvQFKYNdvTuscMYQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,211,1787036400"; d="scan'208";a="8831426" Received: from ettammin-mobl3.ger.corp.intel.com (HELO localhost) ([10.245.244.148]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Nov 2026 06:44:10 -0800 Date: Fri, 13 Nov 2026 16:44:08 +0200 From: Andy Shevchenko To: Alejandro Colomar Cc: linux-hardening@vger.kernel.org, Krzysztof Kozlowski , "Maciej W. Rozycki" , Geert Uytterhoeven , Andreas Schwab , Andy Shevchenko , Bartosz Golaszewski , Daniel Scally , Danilo Krummrich , Greg Kroah-Hartman , Hans Verkuil , Heikki Krogerus , Joe Perches , Johan Hovold , Kees Cook , Laurent Pinchart , Len Brown , Linus Torvalds , Linus Walleij , Namhyung Kim , "Rafael J. Wysocki" , Rob Herring , Sakari Ailus , Saravana Kannan , Steven Rostedt , Tom Zanussi , linux-acpi@vger.kernel.org, driver-core@lists.linux.dev, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-gpio@vger.kernel.org Subject: Re: [PATCH v5 7/7] string: Implement strstarts() with strprefix() Message-ID: References: <382a44f7c68672ecead2436d9f569ee23f383830.1794574496.git.alx@kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <382a44f7c68672ecead2436d9f569ee23f383830.1794574496.git.alx@kernel.org> Organization: Intel Finland Oy - BIC 0357606-4 - c/o Alberga Business Park, 6 krs, Bertel Jungin Aukio 5, 02600 Espoo On Fri, Nov 13, 2026 at 02:11:17PM +0100, Alejandro Colomar wrote: > The compiler should be able to optimize out the unused pointer > arithmetic done at the end, so performance-wise this shouldn't change > anything. If strprefix() is not inline how would it be done? Or I missed the point? > This change de-duplicates the almost-identical implementations, > and better shows the relationship between the two functions. ... > static inline bool strstarts(const char *str, const char *prefix) > { > - return strncmp(str, prefix, strlen(prefix)) == 0; > + return strprefix(str, prefix); > } There is no sense to keep strstarts() at this point. Can it be simply redefinition? However, after looking at the uses in the kernel, I prefer to see the strprefix() be not implemented at all, just optimization against strstarts()/strends() if required can be performed. -- With Best Regards, Andy Shevchenko