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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 4A4ABC10F28 for ; Sun, 8 Mar 2020 08:10:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 216422072A for ; Sun, 8 Mar 2020 08:10:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583655001; bh=U09xjohhRqqV+2chi3p5cHIE4DNl19xwTDy0XvNaRGU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eaToZLifda4oZqjW8+1RSHk8F9S48WaUAyNByLBvMyWM487AwRVSan9/KrI1byp6T 67qrI6oc7Hf6dEgZtMLab09d+csEya9o62LsHndgk1PacHviKha7IwQpiUjGUThIlD +Nrms4tnj0Wyr2WoE5Iey+4UZDo4egMnzSV47sy4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726643AbgCHIJ7 (ORCPT ); Sun, 8 Mar 2020 04:09:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:37466 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726271AbgCHIJ4 (ORCPT ); Sun, 8 Mar 2020 04:09:56 -0400 Received: from e123331-lin.home (amontpellier-657-1-18-247.w109-210.abo.wanadoo.fr [109.210.65.247]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 20A3120848; Sun, 8 Mar 2020 08:09:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583654996; bh=U09xjohhRqqV+2chi3p5cHIE4DNl19xwTDy0XvNaRGU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dz2QgcK+o3ZtT+2LcDa2r18afZ9B2NCbxTxl4ts7sJ8E5Q698ZpQLCyk8jJqKxcT/ P5yVL6JXHrY9inkBk6AQl+l1l9XPmpN9rj1kq64XGAbXAkbLtPuv+8nhEYjE9IAFU2 kkrmyDj2M0NXErs64EyflCtr9d4HPzf34+AOSf0Q= From: Ard Biesheuvel To: linux-efi@vger.kernel.org, Ingo Molnar , Thomas Gleixner Cc: Ard Biesheuvel , linux-kernel@vger.kernel.org, Arvind Sankar , Christoph Hellwig , David Hildenbrand , Davidlohr Bueso , Guenter Roeck , Heinrich Schuchardt , Jonathan Corbet , Lukas Bulwahn , Masahiro Yamada , Nikolai Merinov , Tom Lendacky , Vladis Dronov Subject: [PATCH 14/28] efi/libstub/x86: deal with exit() boot service returning Date: Sun, 8 Mar 2020 09:08:45 +0100 Message-Id: <20200308080859.21568-15-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200308080859.21568-1-ardb@kernel.org> References: <20200308080859.21568-1-ardb@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Even though it is uncommon, there are cases where the Exit() EFI boot service might return, e.g., when we were booted via the EFI handover protocol from OVMF and the kernel image was specified on the command line, in which case Exit() attempts to terminate the boot manager, which is not an EFI application itself. So let's drop into a deadloop instead. Tested-by: Nathan Chancellor # build Link: https://lore.kernel.org/r/20200303080648.21427-1-ardb@kernel.org [ardb: put 'hlt' in deadloop] Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/x86-stub.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/efi/libstub/x86-stub.c b/drivers/firmware/efi/libstub/x86-stub.c index 7f3e97c2aad3..69a942f0640b 100644 --- a/drivers/firmware/efi/libstub/x86-stub.c +++ b/drivers/firmware/efi/libstub/x86-stub.c @@ -344,7 +344,8 @@ static void setup_graphics(struct boot_params *boot_params) static void __noreturn efi_exit(efi_handle_t handle, efi_status_t status) { efi_bs_call(exit, handle, status, 0, NULL); - unreachable(); + for(;;) + asm("hlt"); } void startup_32(struct boot_params *boot_params); -- 2.17.1