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 X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2E311C48BD6 for ; Tue, 25 Jun 2019 18:05:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EDDD1208E3 for ; Tue, 25 Jun 2019 18:05:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="aNcnUZtE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732832AbfFYSFb (ORCPT ); Tue, 25 Jun 2019 14:05:31 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:37049 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726761AbfFYSFa (ORCPT ); Tue, 25 Jun 2019 14:05:30 -0400 Received: by mail-ed1-f68.google.com with SMTP id w13so28459685eds.4 for ; Tue, 25 Jun 2019 11:05:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=y0z5BxDxKG6mK/2TjsyaVPnCqxPuFcpMaFT0ffP2suQ=; b=aNcnUZtEYD7BtlT4ufo2DokTdV5JtlOc88TyNpRjxOMgQv6/1AwJPgqoYCiaQhubYp WjdX2RIXMbrBXKtT7ULOz7TZAFZDrz8hDqTtTgwLHMzvgc3A71mZpC/3bOp6MhJluhgs wRg00iX97g0qoEsjW7wtEYp80KFJ6I/G+StHq+nw5ZDChHVl3rNEGSbzDruZbRqJWDFt Qx6E/QlsIBO3Bgg9QqKkaovwRysf8VHxyHmAmlxy/pdEjJ1eN4AOrHrA5izofUFwyDFA 2KfRPIbt8X0U/Rw/LcnHCtx/d5CYmm4AN/blU+z/xnoCHKba8efv+GIptfUbaYYKHv1p n2xg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=y0z5BxDxKG6mK/2TjsyaVPnCqxPuFcpMaFT0ffP2suQ=; b=Lw7xy4mD21GyyVY/Z6EyZO2+2gUj0UuXHbpMp1RODuditUIodm2tCe1Zl8R18uQoUM XJMFgZpcZvQIyEgauIYA66/AE7ILPtVFkYDZE0YmI5vNew+4uo2Gc0XMBgjqya7ioaFD 2mCXCu8mo2Hti/EbvrABXk7hUt7uQtEbGkYikRnNr6uRAP5j6fgqBuBptarQYNIlGpz/ Yb0lr+Ioh/ksCAq5M8XzhAwH3q09n3/+dmQCxvegl771BMY+Hn3d3k2vprknT1B/Ettc ieaz71R/WSbtbpzlP3zhIGVP/HR2Co5vbsKDZ+9YnKb6iXQvc2s0Pd0NGaHWSyg+r5DY xHzQ== X-Gm-Message-State: APjAAAVULjndxPa7nTJ66i7uDCRsEDoTBeQogEBVn9FU8V0oZOaQKVoP KFCdtLlqSv/EKOVan/YJf+A= X-Google-Smtp-Source: APXvYqwK/4c6xC0XUaZohjb8X/oY4ixHMzj1ndM08hF3f/kDkJlcRAXmVMV5XSn/iyZeVMMhnskSPA== X-Received: by 2002:a50:b3d0:: with SMTP id t16mr104313495edd.158.1561485928085; Tue, 25 Jun 2019 11:05:28 -0700 (PDT) Received: from archlinux-epyc ([2a01:4f9:2b:2b15::2]) by smtp.gmail.com with ESMTPSA id j13sm677928ejt.13.2019.06.25.11.05.26 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Tue, 25 Jun 2019 11:05:27 -0700 (PDT) Date: Tue, 25 Jun 2019 11:05:25 -0700 From: Nathan Chancellor To: Kees Cook Cc: Peter Zijlstra , Miguel Ojeda , "Gustavo A. R. Silva" , Joe Perches , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Thomas Gleixner , Borislav Petkov , "H. Peter Anvin" , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Kan Liang , linux-kernel , Shawn Landden Subject: Re: [PATCH] perf/x86/intel: Mark expected switch fall-throughs Message-ID: <20190625180525.GA119831@archlinux-epyc> References: <20190624161913.GA32270@embeddedor> <20190624193123.GI3436@hirez.programming.kicks-ass.net> <20190624203737.GL3436@hirez.programming.kicks-ass.net> <3dc75cd4-9a8d-f454-b5fb-64c3e6d1f416@embeddedor.com> <20190625071846.GN3436@hirez.programming.kicks-ass.net> <201906251009.BCB7438@keescook> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201906251009.BCB7438@keescook> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 25, 2019 at 10:12:42AM -0700, Kees Cook wrote: > On Tue, Jun 25, 2019 at 09:18:46AM +0200, Peter Zijlstra wrote: > > Can it build a kernel without patches yet? That is, why should I care > > what LLVM does? > > Yes. LLVM trunk builds and boots x86 now. As for distro availability, > AIUI, the asm-goto feature missed the 9.0 LLVM branch point, so it'll > appear in the following release. > > -- > Kees Cook I don't think that's right. LLVM 9 hasn't been branched yet so it should make it in. http://lists.llvm.org/pipermail/llvm-dev/2019-June/133155.html If anyone wants to play around with it before then, we wrote a self-contained script that will build an LLVM toolchain suitable for kernel development: https://github.com/ClangBuiltLinux/tc-build Cheers, Nathan