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[209.132.180.67]) by mx.google.com with ESMTP id y23-v6si1733494pli.633.2018.02.14.09.32.11; Wed, 14 Feb 2018 09:32:35 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=HJNiP3OA; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1161215AbeBNRbZ (ORCPT + 99 others); Wed, 14 Feb 2018 12:31:25 -0500 Received: from mail-vk0-f65.google.com ([209.85.213.65]:40706 "EHLO mail-vk0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1161026AbeBNRbY (ORCPT ); Wed, 14 Feb 2018 12:31:24 -0500 Received: by mail-vk0-f65.google.com with SMTP id o17so6060256vke.7 for ; Wed, 14 Feb 2018 09:31:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=QYiI7Xd8uifDbuxujFXHa/d2xsfcK0eMonjjPHSCdKU=; b=HJNiP3OA73ObCY/MKNYjzGbd7uwPeoKp4ZMkA21kmyJWTaFSafcdk/ntbP+KMRKU2v BmY6L7XwBb0XzeyGC00Z2bWOcpGbJZ1cPojIWIYRgWtlVmlCihcPxZBpFkE79DVM4bNH EYsxkHnCfYql6BfQyntJf8sQh6PxGBhPFjteDMhNhsP1ZORTJwu6bNTOXsLvrUtWnS6+ qZBmbPUKpTVCvIbfY6GV4BSBa7h5KxwmEatarHjkiYZd4ev/QiwLR/e0Ph+/krXfKn9r mPGaublkPC5MxPCuMDaCa0FNpMC8QyzaQc2t8Y1p/prhGEZgMD3yEOg3Nr1dZqlC6j/P wBjA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=QYiI7Xd8uifDbuxujFXHa/d2xsfcK0eMonjjPHSCdKU=; b=maP4fmr0zMB0sk1tUra0w522vgwkokDC2pnViHBsek5zeRrwDAZT1vzXHngVbnCqc+ 2aFxPzZz7oXsTUg1yWOIE6Wj2QEFulHjPOt9pVVCwC8P0OjDtOllouuDvEWOfar+GNLw 2KbX9H6s8yZaHyX9IL/TIeaqU25uKiNbtVyQDfALibIq8JEmZ0we8ar9vJTE07QDvB73 kAbxZMl2t8mohuaX6rKKIoKKmLBEcQLF8+zvmtcor3edDbjR9bV85YgGW4NPxg6/1IXL +zQ067dV3VEkfhxAL5u3Hp0WheBOF3iR7yJZJZxzG98VbRnTbHfsMesnY2KVnCiVkvc2 KAOw== X-Gm-Message-State: APf1xPCx+347rkyeuyMdGnqdkyx+VjAUC3ZzlaRMAU6xL+JjsnxjmX1E vslzxQcgMCe1LAoytX1pkt/MC+KVrREzO9RQ3ClMCw== X-Received: by 10.31.230.132 with SMTP id d126mr5303530vkh.123.1518629483207; Wed, 14 Feb 2018 09:31:23 -0800 (PST) MIME-Version: 1.0 Received: by 10.31.56.87 with HTTP; Wed, 14 Feb 2018 09:31:22 -0800 (PST) In-Reply-To: <20180214090851.GU25181@hirez.programming.kicks-ass.net> References: <20180214090851.GU25181@hirez.programming.kicks-ass.net> From: Kees Cook Date: Wed, 14 Feb 2018 09:31:22 -0800 Message-ID: Subject: Re: clang asm-goto support (Was Re: [PATCH v2] x86/retpoline: Add clang support) To: Peter Zijlstra Cc: "Yatsina, Marina" , David Woodhouse , Chandler Carruth , "Kreitzer, David L" , "Grischenko, Andrei L" , "rnk@google.com" , LLVM Developers , "ehsan@mozilla.com" , "Tayree, Coby" , Matthias Braun , Dean Michael Berris , James Y Knight , Guenter Roeck , X86 ML , LKML , Alan Cox , Rik van Riel , Andi Kleen , Josh Poimboeuf , Tom Lendacky , Linus Torvalds , Jiri Kosina , Andy Lutomirski , "Hansen, Dave" , Tim Chen , Greg Kroah-Hartman , Paul Turner , Stephen Hines , Nick Desaulniers Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Feb 14, 2018 at 1:08 AM, Peter Zijlstra wrote: > If you ever get to the point where it makes sense to build a kernel with > LLVM [...] Just to speak to this point in particular: it makes sense to build kernels with LLVM right now. It's already happened; millions of Pixel 2 phones are already running with Clang-built kernels. And even if you're only interested in x86, that works too. -Kees -- Kees Cook Pixel Security