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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5DC29C433EF for ; Thu, 14 Jul 2022 22:18:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241072AbiGNWSx (ORCPT ); Thu, 14 Jul 2022 18:18:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232129AbiGNWSw (ORCPT ); Thu, 14 Jul 2022 18:18:52 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CFC718E3F; Thu, 14 Jul 2022 15:18:50 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 6692BB829D7; Thu, 14 Jul 2022 22:18:49 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 79B57C34115; Thu, 14 Jul 2022 22:18:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1657837127; bh=1Aqwr4YFqfGgDa0bG3vB0f3cqZWIAVz8aqAVl9OSS+s=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=mp0AHknd+XA/uw2dc8IvLvTyMr/8Z+2WjR8HL/0QnxBwakyYZ8WwteB8dbKYiFssA ORKewj7/ZxlpjF4+reE6tAVbOcVoQzZ5RgWme33H82QdkxGeAhjLBAqYKjH0UyH7TF K8crPXQ+jS2ZpaKxJrLNaqMXhPBcT2hu4okc2acAxpxrlN+TK1JU9rJxtGpALtRWUx jTUgxRnugd8KGiYo7C67MNe5zZnSRqgRN6SPGbMP2Z/d3toHyQglIzLnYrzCjMbmeE d7sDjKv2yT1Q6pm03GTU/jzejOvhg95odFgIwl2/8QDm8jMggsWMUy2dYk86w4SRaI +KWmYMn0rusDg== Date: Thu, 14 Jul 2022 15:18:45 -0700 From: Jakub Kicinski To: Linus Torvalds Cc: Nathan Chancellor , Peter Zijlstra , Borislav Petkov , "the arch/x86 maintainers" , Nick Desaulniers , Josh Poimboeuf , Linux Kernel Mailing List , clang-built-linux , stable , kernel test robot Subject: Re: [PATCH v2] x86/speculation: Use DECLARE_PER_CPU for x86_spec_ctrl_current Message-ID: <20220714151845.59905190@kernel.org> In-Reply-To: References: <20220713152436.2294819-1-nathan@kernel.org> <20220714143005.73c71cf8@kernel.org> <20220714145652.22cf4878@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 14 Jul 2022 15:14:53 -0700 Linus Torvalds wrote: > On Thu, Jul 14, 2022 at 2:56 PM Jakub Kicinski wrote: > > I have clang 13, let me double check this fix is enough for the build > > to complete without disabling WERROR. > > I have clang 14 locally, and it builds fine with that (and doesn't > build without it). FWIW I can confirm - builds with clang 13 as well. > I actually normally build the kernel with both gcc and clang. My > "upstream" kernel I build with gcc, and then I have my "private random > collection of patches" kernel that I build with clang and that are > just rebased on top of the kernel-of-the-day. > > This is all entirely for historical reasons - part of my "private > random collection of patches" used to be the "asm goto with outputs", > which had clang support first. > > But then the reason I never even noticed the build breakage with the > retbleed patches until much too late was that those I just had as a > third fork off my upstream kernel, so despite me usually building with > clang too, that only got attention from gcc. > > So it's really just a microcosm version of the exact same bigger issue > we always have with those embargoed hw security patches: they end up > missing out on all the usual test environments. > > Anyway, I cherry-picked Nathan's patch from my clang tree and pushed > it out as commit db886979683a ("x86/speculation: Use DECLARE_PER_CPU > for x86_spec_ctrl_current"). Awesome, thanks!