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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 95D87CA9ED4 for ; Mon, 4 Nov 2019 22:23:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6C51C204EC for ; Mon, 4 Nov 2019 22:23:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572906233; bh=BQznuFgVQfqp84u8/GPWmIUgThSN1012WBeQa99r7uE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ij1Lo4UXMONaESJ1MMInkoQ3dcetnFGVt2FGPer3eS64MQUsOra1HzSUZ0Dcevq4P S86Ez1f1ErAeJn02gsPfWy1iq8ZW8phwJOZxPjeHEILtV5IaP3nxpNPMalEroADHXI kQMAnlp++Wv4ZJmwrK2UcCPuS2zl8W3Ym6qdDyGo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387470AbfKDVxv (ORCPT ); Mon, 4 Nov 2019 16:53:51 -0500 Received: from mail.kernel.org ([198.145.29.99]:47980 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387588AbfKDVxu (ORCPT ); Mon, 4 Nov 2019 16:53:50 -0500 Received: from localhost (6.204-14-84.ripe.coltfrance.com [84.14.204.6]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id ADE0321D81; Mon, 4 Nov 2019 21:53:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572904429; bh=BQznuFgVQfqp84u8/GPWmIUgThSN1012WBeQa99r7uE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=U1yKKV1YC6Gfe2u1DPFZIokSkBsXcVf3lFEhAdwcAgG1EwXAdbRX8O62HtY1pXKHo /x4/h8+EeCzzG+eeoKd2R6FYx3P+jwpgSZ/kUYXnkU5fVqqNI+m30q43/mk88epzks 7GqG2T7wy8zP3TEoN9Z28V+UcIzDvak1KAHO9WZY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, 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 4.14 42/95] efi/x86: Do not clean dummy variable in kexec path Date: Mon, 4 Nov 2019 22:44:40 +0100 Message-Id: <20191104212101.999539577@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191104212038.056365853@linuxfoundation.org> References: <20191104212038.056365853@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@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 9061babfbc83d..335a62e74a2e9 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -893,9 +893,6 @@ 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