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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 B0717C2BA17 for ; Mon, 6 Apr 2020 15:53:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8666C248F6 for ; Mon, 6 Apr 2020 15:53:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="j4FkMrO6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729155AbgDFPxp (ORCPT ); Mon, 6 Apr 2020 11:53:45 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:46103 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729118AbgDFPxl (ORCPT ); Mon, 6 Apr 2020 11:53:41 -0400 Received: by mail-pf1-f193.google.com with SMTP id q3so7690274pff.13; Mon, 06 Apr 2020 08:53:39 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=JOdtzdnnmad/Wdl1KcR4OtWl2QzBvVS5vHN6ckHY/5o=; b=j4FkMrO6qcS5FreIFpVHyuw0A7eYKdb+hjsIGJ5vYGUmNnjpkcaX8wL1smr1eLf5eP 8kiw5sw3Fg6uMqQVwvrw580/pKUaDy3htxXqazL/mI90iC33lzZyKoTFDO1g4OXgq0PC OCl7C0JvQZ1WMPETUAqOktZ4EGkKCc40ZhzV+9h6gkhNoQKDUzNZ8CuG/2KxbEEucjTs TcOmVVbdIwLR8NBx0kDd8nWS2E5YbFGzXfEOk4uOcV0KhHyh+ssrBew6Mrctu0oXWt4V wt9yN5cu4DaCbe5nQcO6HEHyV9BJfLhXzQv64KW1DNIRoMSZ72NPqzc25+nMD1vILzOo cBDg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=JOdtzdnnmad/Wdl1KcR4OtWl2QzBvVS5vHN6ckHY/5o=; b=Do8vz10aDkHCjKXJTseh16S81lhCFfJFNr/zI5sEH66WHjpy1DTwEv9D1wz4HxRqUB 1kJR1n4qa2eHkOgaU8Ag70HQE+3nTrznql85/QujsNShPbUGfdIB43JN8WRTu9V3CWBq /R7TH+ZQNN75NvAE2dkTI0hGkJ/oX6QIDDiCtdG4lA1W8lmtFmVOnKYzc9WWx5SzsUyL Dn58BgCFfnrYQrvGXnvg9uoELyCA4hKUnGgcpxE/2ts+oPyxCM75GnbBPB0fUjmcqXqn 9vDSAqsHM7RaFIVgnK3QGlOf5w8iNlom+0tIi9jKTgtfOXdPrbEJeN5JtgNtZ1u34QwU AbRA== X-Gm-Message-State: AGi0PuYL9fNus1kRziWtHg2R5ddAxVi7wkUqL2SO2qkWZieO1B/3sXdA hV2Zi6jFG3IMIswyWGcV5uM= X-Google-Smtp-Source: APiQypJM4CyZ4KvQcH0D4+3j4klbrijx7sBt+/Q06gPB9JAEM3q9WJsrRsOkIQ2BjK0eNUM3vzjuGw== X-Received: by 2002:a63:258:: with SMTP id 85mr11021906pgc.38.1586188418827; Mon, 06 Apr 2020 08:53:38 -0700 (PDT) Received: from localhost.corp.microsoft.com ([131.107.160.210]) by smtp.googlemail.com with ESMTPSA id 79sm11823275pfz.23.2020.04.06.08.53.37 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 06 Apr 2020 08:53:38 -0700 (PDT) From: ltykernel@gmail.com X-Google-Original-From: Tianyu.Lan@microsoft.com To: kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com, liuwe@microsoft.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, x86@kernel.org, arnd@arndb.de, michael.h.kelley@microsoft.com Cc: Tianyu Lan , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, vkuznets@redhat.com Subject: [PATCH V4 4/6] x86/Hyper-V: Report crash register data or kmsg before running crash kernel Date: Mon, 6 Apr 2020 08:53:29 -0700 Message-Id: <20200406155331.2105-5-Tianyu.Lan@microsoft.com> X-Mailer: git-send-email 2.14.5 In-Reply-To: <20200406155331.2105-1-Tianyu.Lan@microsoft.com> References: <20200406155331.2105-1-Tianyu.Lan@microsoft.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Tianyu Lan We want to notify Hyper-V when a Linux guest VM crash occurs, so there is a record of the crash even when kdump is enabled. But crash_kexec_post_notifiers defaults to "false", so the kdump kernel runs before the notifiers and Hyper-V never gets notified. Fix this by always setting crash_kexec_post_notifiers to be true for Hyper-V VMs. Fixes: 81b18bce48af ("Drivers: HV: Send one page worth of kmsg dump over Hyper-V during panic") Reviewed-by: Michael Kelley Signed-off-by: Tianyu Lan --- Change since v1: Update commit log Change since v3: - Add fix commit in the change log. --- arch/x86/kernel/cpu/mshyperv.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c index caa032ce3fe3..5e296a7e6036 100644 --- a/arch/x86/kernel/cpu/mshyperv.c +++ b/arch/x86/kernel/cpu/mshyperv.c @@ -263,6 +263,16 @@ static void __init ms_hyperv_init_platform(void) cpuid_eax(HYPERV_CPUID_NESTED_FEATURES); } + /* + * Hyper-V expects to get crash register data or kmsg when + * crash enlightment is available and system crashes. Set + * crash_kexec_post_notifiers to be true to make sure that + * calling crash enlightment interface before running kdump + * kernel. + */ + if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) + crash_kexec_post_notifiers = true; + #ifdef CONFIG_X86_LOCAL_APIC if (ms_hyperv.features & HV_X64_ACCESS_FREQUENCY_MSRS && ms_hyperv.misc_features & HV_FEATURE_FREQUENCY_MSRS_AVAILABLE) { -- 2.14.5