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,URIBL_BLOCKED,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 64E18CA9EA9 for ; Fri, 18 Oct 2019 22:12:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 339AD21D7C for ; Fri, 18 Oct 2019 22:12:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571436721; bh=vhLLu4Q3ANV96K9R9BBwMJ7SfEgIHXx42oFIcggazeo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=jPs9UuxJqwavUc+EPqDN473gvPxY1wgEuIHkaiTkblOTo0kdCN3DqblBwT2Qq62fH hYDw5sp/DNmWTWMwFfHBBz3Vql1wBeS5sz3nR2frjScDS1SKTbeKqP5SSoohGocRRC oallS/UVHEHetw2NmpKTbVgd7W7g93CITnDbmGDU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390195AbfJRWK3 (ORCPT ); Fri, 18 Oct 2019 18:10:29 -0400 Received: from mail.kernel.org ([198.145.29.99]:43412 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390102AbfJRWK3 (ORCPT ); Fri, 18 Oct 2019 18:10:29 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (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 6ED4822474; Fri, 18 Oct 2019 22:10:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1571436628; bh=vhLLu4Q3ANV96K9R9BBwMJ7SfEgIHXx42oFIcggazeo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=j/U/S3OH5a541G28VJ24XlddlyM4h+klwPf787X09xZ7ofhoxkEsX8I0tN0lez2/I d5f0enVjB5/sJrIF2H9kT7dxYh1wngcaFtrGzwbasMWUpE84DahB9z7ub94r6XS4R/ 5CPYyP/z39Djmn8iP2PG0AeOa8uZg1Tq5Iz4B15I= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Dave Young , Ard Biesheuvel , Matthew Garrett , Ben Dooks , Jarkko Sakkinen , Jerry Snitselaar , Linus Torvalds , Lukas Wunner , Lyude Paul , Octavian Purdila , Peter Jones , Peter Zijlstra , Scott Talbert , Thomas Gleixner , linux-efi@vger.kernel.org, linux-integrity@vger.kernel.org, Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL 4.4 13/21] efi/x86: Do not clean dummy variable in kexec path Date: Fri, 18 Oct 2019 18:09:59 -0400 Message-Id: <20191018221007.10851-13-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191018221007.10851-1-sashal@kernel.org> References: <20191018221007.10851-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-efi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org From: Dave Young [ Upstream commit 2ecb7402cfc7f22764e7bbc80790e66eadb20560 ] kexec reboot fails randomly in UEFI based KVM guest. The firmware just resets while calling efi_delete_dummy_variable(); Unfortunately I don't know how to debug the firmware, it is also possible a potential problem on real hardware as well although nobody reproduced it. The intention of the efi_delete_dummy_variable is to trigger garbage collection when entering virtual mode. But SetVirtualAddressMap can only run once for each physical reboot, thus kexec_enter_virtual_mode() is not necessarily a good place to clean a dummy object. Drop the efi_delete_dummy_variable so that kexec reboot can work. Signed-off-by: Dave Young Signed-off-by: Ard Biesheuvel Acked-by: Matthew Garrett Cc: Ben Dooks Cc: Jarkko Sakkinen Cc: Jerry Snitselaar Cc: Linus Torvalds Cc: Lukas Wunner Cc: Lyude Paul Cc: Octavian Purdila Cc: Peter Jones Cc: Peter Zijlstra Cc: Scott Talbert Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Cc: linux-integrity@vger.kernel.org Link: https://lkml.kernel.org/r/20191002165904.8819-8-ard.biesheuvel@linaro.org Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- arch/x86/platform/efi/efi.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index ad285404ea7f5..4bc352fc08f19 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -859,9 +859,6 @@ static void __init kexec_enter_virtual_mode(void) if (efi_enabled(EFI_OLD_MEMMAP) && (__supported_pte_mask & _PAGE_NX)) runtime_code_page_mkexec(); - - /* clean DUMMY object */ - efi_delete_dummy_variable(); #endif } -- 2.20.1