From patchwork Tue Jan 28 01:54:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Fainelli X-Patchwork-Id: 232778 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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 E0C21C33CB7 for ; Tue, 28 Jan 2020 01:54:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD46424685 for ; Tue, 28 Jan 2020 01:54:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="IMCV0kwE" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726173AbgA1ByW (ORCPT ); Mon, 27 Jan 2020 20:54:22 -0500 Received: from mail-pl1-f193.google.com ([209.85.214.193]:46666 "EHLO mail-pl1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726164AbgA1ByW (ORCPT ); Mon, 27 Jan 2020 20:54:22 -0500 Received: by mail-pl1-f193.google.com with SMTP id y8so4446832pll.13; Mon, 27 Jan 2020 17:54:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=1ZMMwelLf0A5wvuZj2x68zePfxAq2fUXhD1Zlvefv7Y=; b=IMCV0kwEhLFtqutPkJoXbViyl3w7xBFWsjPH9LRk1eSZEDxFU+qs04YB1NuSl1GJY4 OqExxvsOXGJO53LAWvbkaDdFYzUDDL8Q+X+/v+oSWVN8xHwG8Sr2amcUUIqLPxgte1uS wqpEUn2XG7Hh2mzFMC5TUonmyjgSuROS8yaTYlkQ0PakyV5iMft6t6F984i9sg6l3UKB n4FycKWpp1tCgK9Oh7cJMoAsJbvPQJDsDv4IZPtdLF6+3/8ceNI1MpkhSsI60El2Fipq jIKaOevJAk1CL1fOgHV7Q5CyhOfoDtrp7oAc1qn3y/doQ6JYx5UO1G+AIIUET+FDPB7+ n+3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=1ZMMwelLf0A5wvuZj2x68zePfxAq2fUXhD1Zlvefv7Y=; b=cxhxIkLroE+tQYAjIzQJWUh4rQT3fzfHgcw5k5dmkfdZwvAUC4eDCPioMEWYksno6w E253efisCcBYOAoc1Hx9VkDPO2KVsJHC7x/f8WjduNWZyp2MACiUlpo7oWbDwirtH/Rv GWbR5u6EjRJngLVb30uC7lS/kT59b38hkTo+iiwTtYeFhHRGGJv4CsjzoWYDxv1b7QH+ GmjZO4Y4fEH70KMhkFC7SA2nvrixrQGrpwp8kuk2ZO5QoWE/C8TAQ5HUqfIzK/X6f63L yTPF14a3u8zaOXZyNavvMdTv6P7FSyUNdCjeJc2s6VK9KqiBjyTQL6Op/jpOt+BHRxRh AdIw== X-Gm-Message-State: APjAAAX/PuuEPscJf/9tyUjHqXAZGUTGdJ8bdQsGSeEMI1/N4i2Llu2X ocMcgOVIPTocz8KD1XKOncoc45rD X-Google-Smtp-Source: APXvYqzSCLsgdu+thMaqEiaZLIgj4vYPC2rYGh4W/mehpz0fI9OBBI2eSwUmj0peH72azDJW1dMcQQ== X-Received: by 2002:a17:902:d711:: with SMTP id w17mr20998616ply.303.1580176461737; Mon, 27 Jan 2020 17:54:21 -0800 (PST) Received: from localhost.localdomain ([192.19.224.250]) by smtp.gmail.com with ESMTPSA id j17sm17393234pfa.28.2020.01.27.17.54.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jan 2020 17:54:21 -0800 (PST) From: Florian Fainelli To: linux-vger@kernel.org Cc: stable@vger.kernel.org, jeremy.linton@arm.com, gregkh@linuxfoundation.org, sashal@kernel.org, Jonathan Corbet , Florian Fainelli , linux-doc@vger.kernel.org (open list:DOCUMENTATION), linux-kernel@vger.kernel.org (open list) Subject: [PATCH stable-4.9] Documentation: Document arm64 kpti control Date: Mon, 27 Jan 2020 17:54:14 -0800 Message-Id: <20200128015415.2276-1-f.fainelli@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jeremy Linton commit de19055564c8f8f9d366f8db3395836da0b2176c upstream For a while Arm64 has been capable of force enabling or disabling the kpti mitigations. Lets make sure the documentation reflects that. Signed-off-by: Jeremy Linton Reviewed-by: Andre Przywara Signed-off-by: Jonathan Corbet [florian: patch the correct file] Signed-off-by: Florian Fainelli --- Documentation/kernel-parameters.txt | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 1bc12619bedd..b2d2f4539a3f 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -1965,6 +1965,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. kmemcheck=2 (one-shot mode) Default: 2 (one-shot mode) + kpti= [ARM64] Control page table isolation of user + and kernel address spaces. + Default: enabled on cores which need mitigation. + 0: force disabled + 1: force enabled + kstack=N [X86] Print N words from the kernel stack in oops dumps.