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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 050AAC5DF60 for ; Tue, 5 Nov 2019 23:56:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A3DFA2077B for ; Tue, 5 Nov 2019 23:56:29 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="QDgKQccA" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730679AbfKEX42 (ORCPT ); Tue, 5 Nov 2019 18:56:28 -0500 Received: from mail-qt1-f202.google.com ([209.85.160.202]:55933 "EHLO mail-qt1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730579AbfKEX41 (ORCPT ); Tue, 5 Nov 2019 18:56:27 -0500 Received: by mail-qt1-f202.google.com with SMTP id u23so24225651qtb.22 for ; Tue, 05 Nov 2019 15:56:26 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=E806Ihq7Qr5kwAxZ8O8jq/5GK0i44oON304BuEfvZ08=; b=QDgKQccAQsH+R5h45PS8H6bNgjwH8RGSJOkAG/AGuoy5YWBicw4QukLKRyaCj/ZX4C S4zge4BSm47qikuijSk/1DeLDJdEzJKyjjpMkCVFyBe8iRT+BVtRIzaIEOM4Sg8kMqqp 19PNx89unPNFUWHLbXlCN0veqqqj3T/UMrnqvSODWT2d26uSn9YoutJHq9olqlmfvgF9 quHA5kvZggYfAPkKhiPNj+ueCkFnNP+twN85T1uWZaZ2Qu7624dIYDxVRZ2i6SnFYV+M zMwC8p5EGVUt8lQAk9+5QoxNLcfzBFJJ4Q7ld+hIBbOPsyda1IzIoSUjKf8hfnCm4zFw faOg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=E806Ihq7Qr5kwAxZ8O8jq/5GK0i44oON304BuEfvZ08=; b=KDaaHpjqn0eo66FEnhZbH0C3dKP1BVw++RMdFvmLUAe1g0AIJWviZlnVjoaNmG7kzV TRQw4MWTk1MhpcpIF0ZC0jM3sFp2aTZVwtV2QRpazwb9rvLNjM5mOAPK9IU0F1JBzsFB h4LR/on7QRYI4aTGTnlJQ412TrKxZ/SzkT7Vp4XI9ZhIXVUGrjKvcutxPQkoTudPaePx Ml1XYBsHbkkmihr3jJ/U2Yh1Gj3HhtruRM6jtIakMkAsyCUi8XPr0U6Yy1ae/gVDDxMY iXq9X60vM07Ax2Isxv6gk2GsV8JDOeH7qvNO/+78KLH6xf9wxEODeiffjkD8vFZrqLoj MZtQ== X-Gm-Message-State: APjAAAVvhgBXl9lQjMsniO7fBbXmjshQFt44PTLyieRcIPH7KygXBs7P +l36mQmXrg3ZzvYhn5Xo4nyan8Ve6RFxqqTfmgk= X-Google-Smtp-Source: APXvYqwY9fgInvZ1xEGl2M4KIBWFyexAkAf44oIrqVL/dQVZsayL7xfxT7jFK1V9S1zdWFVq0Hf8BYVOaqf916ictzw= X-Received: by 2002:aed:22c8:: with SMTP id q8mr21652726qtc.0.1572998186120; Tue, 05 Nov 2019 15:56:26 -0800 (PST) Date: Tue, 5 Nov 2019 15:55:58 -0800 In-Reply-To: <20191105235608.107702-1-samitolvanen@google.com> Message-Id: <20191105235608.107702-5-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191105235608.107702-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.rc1.363.gb1bccd3e3d-goog Subject: [PATCH v5 04/14] arm64: kernel: avoid x18 in __cpu_soft_restart From: Sami Tolvanen To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel Cc: Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , Marc Zyngier , Nick Desaulniers , Jann Horn , Miguel Ojeda , Masahiro Yamada , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sami Tolvanen 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 From: Ard Biesheuvel The code in __cpu_soft_restart() uses x18 as an arbitrary temp register, which will shortly be disallowed. So use x8 instead. Link: https://patchwork.kernel.org/patch/9836877/ Signed-off-by: Ard Biesheuvel [Sami: updated commit message] Signed-off-by: Sami Tolvanen Reviewed-by: Mark Rutland Reviewed-by: Kees Cook --- arch/arm64/kernel/cpu-reset.S | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/arm64/kernel/cpu-reset.S b/arch/arm64/kernel/cpu-reset.S index 6ea337d464c4..32c7bf858dd9 100644 --- a/arch/arm64/kernel/cpu-reset.S +++ b/arch/arm64/kernel/cpu-reset.S @@ -42,11 +42,11 @@ ENTRY(__cpu_soft_restart) mov x0, #HVC_SOFT_RESTART hvc #0 // no return -1: mov x18, x1 // entry +1: mov x8, x1 // entry mov x0, x2 // arg0 mov x1, x3 // arg1 mov x2, x4 // arg2 - br x18 + br x8 ENDPROC(__cpu_soft_restart) .popsection -- 2.24.0.rc1.363.gb1bccd3e3d-goog