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=-12.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 96797C433DB for ; Mon, 22 Feb 2021 11:59:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3F18164E24 for ; Mon, 22 Feb 2021 11:59:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230147AbhBVL7K (ORCPT ); Mon, 22 Feb 2021 06:59:10 -0500 Received: from mail.kernel.org ([198.145.29.99]:42402 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230105AbhBVL7H (ORCPT ); Mon, 22 Feb 2021 06:59:07 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 4914A64E15; Mon, 22 Feb 2021 11:58:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1613995104; bh=cX6+zcAFvYLB9KQP4npgFv9p/Y9T3UFAefLKaAVJ7cA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=MEtBdS+pzZVBPR9ZfrHvwUbU8LRoQz7FCSZ16Ws+XJQEGovFiXQj0n6bcaFJadohy QzV37B4gnkaa1wRZY0DBHM2Y9vYSwdb9ITEyVkeDkTnC/xPn9uextV4FkzGIcKWJR+ dJrUhg8x7sR8Okocjn0cLzGuy1nMW0YOTn2YiADr5DEtzNVlUiFi/dppws4uCUpbCr 2oQ/u39Uwjm1LWPZEISNNeZ7XtAZWPhrUdMINVz5qmj3v/mokXgde1++ClEeRllpdX YOJCy+1h9hqYCONnAjuzHHCJTgqWY14/Zep5CfTvo/Tlo1tyLMY22L1dG1zxP5RRR9 43oHdPbH9KTyQ== Date: Mon, 22 Feb 2021 11:58:16 +0000 From: Will Deacon To: Jian Cai Cc: ndesaulniers@google.com, manojgupta@google.com, llozano@google.com, clang-built-linux@googlegroups.com, Nathan Chancellor , David Laight , Russell King , Catalin Marinas , James Morris , "Serge E. Hallyn" , Arnd Bergmann , Masahiro Yamada , Kees Cook , Ard Biesheuvel , Andreas =?iso-8859-1?Q?F=E4rber?= , Ingo Molnar , Linus Walleij , Marc Zyngier , Andrew Morton , Mike Rapoport , Mark Rutland , David Brazdil , James Morse , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [PATCH v4] ARM: Implement SLS mitigation Message-ID: <20210222115816.GA8605@willie-the-truck> References: <20210219201852.3213914-1-jiancai@google.com> <20210219230841.875875-1-jiancai@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210219230841.875875-1-jiancai@google.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: On Fri, Feb 19, 2021 at 03:08:13PM -0800, Jian Cai wrote: > This patch adds CONFIG_HARDEN_SLS_ALL that can be used to turn on > -mharden-sls=all, which mitigates the straight-line speculation > vulnerability, speculative execution of the instruction following some > unconditional jumps. Notice -mharden-sls= has other options as below, > and this config turns on the strongest option. > > all: enable all mitigations against Straight Line Speculation that are implemented. > none: disable all mitigations against Straight Line Speculation. > retbr: enable the mitigation against Straight Line Speculation for RET and BR instructions. > blr: enable the mitigation against Straight Line Speculation for BLR instructions. > > Links: > https://reviews.llvm.org/D93221 > https://reviews.llvm.org/D81404 > https://developer.arm.com/support/arm-security-updates/speculative-processor-vulnerability/downloads/straight-line-speculation > https://developer.arm.com/support/arm-security-updates/speculative-processor-vulnerability/frequently-asked-questions#SLS2 > > Suggested-by: Manoj Gupta > Suggested-by: Nick Desaulniers > Suggested-by: Nathan Chancellor > Suggested-by: David Laight > Suggested-by: Will Deacon > Reviewed-by: Nathan Chancellor > Signed-off-by: Jian Cai > --- Please can you reply to my previous questions? https://lore.kernel.org/linux-arm-kernel/20210217094859.GA3706@willie-the-truck/ (apologies if you did, but I don't see them in the archive or my inbox) Will