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=-0.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no 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 09C1BCA9EA0 for ; Tue, 22 Oct 2019 05:55:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C4BDE2089E for ; Tue, 22 Oct 2019 05:55:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="VeZ/77yC" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387465AbfJVFyO (ORCPT ); Tue, 22 Oct 2019 01:54:14 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:40694 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725907AbfJVFyO (ORCPT ); Tue, 22 Oct 2019 01:54:14 -0400 Received: by mail-wr1-f67.google.com with SMTP id o28so16461398wro.7 for ; Mon, 21 Oct 2019 22:54:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=70+N4pxkreRk5D8qTuATktL5M/ApNQm1mVe3QKo4Ow8=; b=VeZ/77yCO2vkRreTdZF0BmlF3aBW7GYN63ztZ+W9IxGlyzot3aZzQG7XNVjBY7A7oD 5ErFNuJigjHDoajFcUUKer2ZNuRvqeRRkKDFwX0d2Zr1W2J0Sitj3DU47jafk1WpqrB9 RO+JgyMPsgCHPUuHfaLf9mhm0FhMWiroTQMq0AMJS2EyfB2q8y2Uj4BUJeCO2gXI9tCY 6QkWiBS+nVx6fiVGxPNCg3OkhqZK5Cxo3moubEo1LbU3pI9Z3P3SLfQSm8r4r1GEdvXM A3I5Jr0ovB215EmWyJbd+kRIvPhHLcOf8Yw0LDZ75fNBWsAH3Ssp+sYWHP4KD/+V8/GQ /NvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=70+N4pxkreRk5D8qTuATktL5M/ApNQm1mVe3QKo4Ow8=; b=ftdtM3efjZDG7mkFycUdEdO+nCBShvaB6ztNGjD7EDFWxWIGGm74ZS9SQ0KSmQxCoi xh+WvVrkf/PnRjaEQkC9Ix4vWI+HKkHEw0jZEZ50u8N4md9xeqrIHd8dWEcGtH+Dt7US Rzv412rvC0OI0NLn+9dDzbSmcU15CiFsEw1KtqB9WVsvsc+K55PKBZ0vBPoYum72waEh +QUtXy8lHbRX1QihB+2hchDl/dCFpDrkithS7yCTU+nAjuqKXlzf0e9V2UHHpfLuoTWV gs4SSI5wgnmw7slzSnyZcsHRxcvrhwhJ/F6Lc7Z1qcNvs9FfWGwTf/a7sl2KplfRcc1q 579w== X-Gm-Message-State: APjAAAUO+/8PSMwcgGteVjv1uZtilF9EAYSVr5wBBoCpzuFTJVdZO6Y8 oJ7iPgBG+amXvRDme1CQGZFHOI6cEpzZ8cWwjJj25g== X-Google-Smtp-Source: APXvYqwrYnGYkoL34VBIT6H+JNjJm/uZwOLCkW8JDJj+1Q/w7n/LWtklQn1YWpTuz0AHRX28UXgTzenaMPN3dF2ZvS4= X-Received: by 2002:adf:9f08:: with SMTP id l8mr1573796wrf.325.1571723652654; Mon, 21 Oct 2019 22:54:12 -0700 (PDT) MIME-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191018161033.261971-15-samitolvanen@google.com> In-Reply-To: From: Ard Biesheuvel Date: Tue, 22 Oct 2019 07:54:07 +0200 Message-ID: Subject: Re: [PATCH 14/18] arm64: efi: restore x18 if it was corrupted To: Sami Tolvanen Cc: Will Deacon , Catalin Marinas , Steven Rostedt , Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Nick Desaulniers , clang-built-linux , Kernel Hardening , linux-arm-kernel , Linux Kernel Mailing List 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 Tue, 22 Oct 2019 at 00:40, Sami Tolvanen wrote: > > On Sun, Oct 20, 2019 at 11:20 PM Ard Biesheuvel > wrote: > > You'll have to elaborate a bit here and explain that this is > > sufficient, given that we run EFI runtime services with interrupts > > enabled. > > I can add a note about this in v2. This is called with preemption > disabled and we have a separate interrupt shadow stack, so as far as I > can tell, this should be sufficient. Did you have concerns about this? > No concerns, but we should put the above clarification in the commit log.