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 4B603CA9ECB for ; Thu, 31 Oct 2019 16:46:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20ABC20873 for ; Thu, 31 Oct 2019 16:46:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="DwFMzJZ+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728889AbfJaQq6 (ORCPT ); Thu, 31 Oct 2019 12:46:58 -0400 Received: from mail-pg1-f201.google.com ([209.85.215.201]:33949 "EHLO mail-pg1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728874AbfJaQqz (ORCPT ); Thu, 31 Oct 2019 12:46:55 -0400 Received: by mail-pg1-f201.google.com with SMTP id w9so4795372pgl.1 for ; Thu, 31 Oct 2019 09:46:54 -0700 (PDT) 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=aHKOoX9zJAla15qSwjd99c+7iNT/pdKXHfBAM0TSbiA=; b=DwFMzJZ+kUlOAWN2GvdIrb0spmd3RCFaXXrjuk+n93RrGiHVTkKIE8QVClddg7kBDe 7IeZak8mKqDEsiR3pvG5D58rS+2OmcCl2VoAJ8fblz+yYSO2P8d24syfdwx60D462Dgh XCr3cWY+P9lvUhF8i41PfwSmLeFuaKf2xbTVnm6vK5gGs924c4E8sqG7J+640Cc4jSv1 COp3Hpg8QTv21PL1iF/DfTs8X6WtTvBta9g6udg3ODicYi1TP2epIsbDEj+VXTpASGOq p/A+gt82BwR62uCobShpcPv4dkr4CW0qj8ti60vpOnCzk1mJe/Au4gEO3Ke231E6vBr6 8IJA== 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=aHKOoX9zJAla15qSwjd99c+7iNT/pdKXHfBAM0TSbiA=; b=R4bvvzFyluGX/Y32ZngghoHxCRYRW4IUlbULgi/wpHg8oq5qvCtEysMrq9SM//ipUX ePJfYTm8BeWXM/Wy+hYzSGcT0wCn1akENntIzqA2PbWrXDXbFniVrnK980tNhTp+4Lcw BMzVfGu003vQZ5ueSOF7V6QiLsB811c/Pvw84NFKJtt6Tz93rmofE5eezM1OaPAxhMpt Eqbc5X1V2HfE85Qi/AUDnIaXInOlcD03LAnFC0vXvRovc5fBre9kgqJT7xxSD8emwl/H KbJYe9rTvEaSYVAnxDrgSnILdr+wPb5Q4mCTPrR/lXPl+O/2AqRk1R73KnlPQKNjseV1 YwPg== X-Gm-Message-State: APjAAAVPkAo3MfNgdHfBwDgMuuX8BB/0/tukXVWbXfaE90kU7ng0XPHq Ra83uXHuOLxJ9IXz0heFDTWQE94xE3LJMAjMSAY= X-Google-Smtp-Source: APXvYqzWKFl/JealEA2qBs8OC840r89CQ5kizTD5lUFGsTusSG0GdYwJSJp9KVbGkb+yd42ZvImlbPdCOavSDAkzBMQ= X-Received: by 2002:a63:1904:: with SMTP id z4mr7825364pgl.413.1572540414204; Thu, 31 Oct 2019 09:46:54 -0700 (PDT) Date: Thu, 31 Oct 2019 09:46:24 -0700 In-Reply-To: <20191031164637.48901-1-samitolvanen@google.com> Message-Id: <20191031164637.48901-5-samitolvanen@google.com> Mime-Version: 1.0 References: <20191018161033.261971-1-samitolvanen@google.com> <20191031164637.48901-1-samitolvanen@google.com> X-Mailer: git-send-email 2.24.0.rc0.303.g954a862665-goog Subject: [PATCH v3 04/17] arm64: kernel: avoid x18 __cpu_soft_restart From: samitolvanen@google.com To: Will Deacon , Catalin Marinas , Steven Rostedt , Masami Hiramatsu , Ard Biesheuvel Cc: Dave Martin , Kees Cook , Laura Abbott , Mark Rutland , 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 Signed-off-by: Sami Tolvanen Reviewed-by: Mark Rutland --- 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.rc0.303.g954a862665-goog