From patchwork Thu Oct 31 16:46:24 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 178209 Delivered-To: patch@linaro.org Received: by 2002:a92:409a:0:0:0:0:0 with SMTP id d26csp3102457ill; Thu, 31 Oct 2019 09:47:01 -0700 (PDT) X-Google-Smtp-Source: APXvYqyRYwAr6s/e06VXRAAtFcJA77wIsO5jHUvIJuUOJir8ExRCos0NJYJnEv/bn35iD4/D2VuR X-Received: by 2002:a17:906:f48:: with SMTP id h8mr5185868ejj.106.1572540420859; Thu, 31 Oct 2019 09:47:00 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1572540420; cv=none; d=google.com; s=arc-20160816; b=UZ+TQ+sVXIn5S014wdwmeaCQJ0vhjB8U8AyQfo1tPHzJgYVfOexRFGjKu+DJ6d9HvI nXWSFWYZIBzBURykdtIKnmyxFQtL+pelaYPorQnb2HNt5T8TplZLfmiqxgknEMAmHw/S Bz0BOx3GG/Cit4pv9Qp1OpBE8QSMeVeJCwVFYovG2XQ7W5YC2aMc8CKGXAIARqOdvhcm detiF7BZFyGoxbTXg05OLeLgGaqjSP0NRuTY3CmrPTUaKgG7ZPtVyA81p/vQpRpnifWm sPz3WwshnuxWtuV/b7dOACfqT5Z+LV7bCQ+vZnc9K8i0tcpUL5jFN5IpNXPpVcuc4iWn 7lFw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:cc:to:from:subject:references :mime-version:message-id:in-reply-to:date:dkim-signature; bh=aHKOoX9zJAla15qSwjd99c+7iNT/pdKXHfBAM0TSbiA=; b=DkW3+aPf2p4gcosjOQyK7n6x+w1ngOXzYP6Fw+YRyMTOz4kfPnACQTQQAouhdxY5bc nHIUNYnFH1NjbTpnaj6DEO5YBFovXTrp0xp/e3jv9Fqmv3gUBw4LXkDMPvo2SDIZjR9y 6BTw0cAsGXEupM5pvhvZAcVTzYSk2mETtEEy6O3SuQ4U6s9bEx8QR1n7F9/MOI8wxlwn qiLhN6cCmqGc8bX4oJ/RL1q1/TeVFi1YMw7GLXU5hCzvqSG5b7TRrBQYwrDaPJ1T/kUB 8R/LFdh9+c2+5hP2bGQKZpOXlQ91V0n8P8mimqMqzK3nG+p7mQwNOv41ug7rwWkNZ1rb Stvw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=DwFMzJZ+; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id l15si4257140edb.81.2019.10.31.09.47.00; Thu, 31 Oct 2019 09:47:00 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20161025 header.b=DwFMzJZ+; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728889AbfJaQq6 (ORCPT + 26 others); 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-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 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(-) -- 2.24.0.rc0.303.g954a862665-goog Reviewed-by: Kees Cook 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