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=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 19D74C18E5B for ; Tue, 17 Mar 2020 13:25:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CE78C20738 for ; Tue, 17 Mar 2020 13:25:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="r6lEtRqd" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726740AbgCQNZp (ORCPT ); Tue, 17 Mar 2020 09:25:45 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:38230 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726598AbgCQNZd (ORCPT ); Tue, 17 Mar 2020 09:25:33 -0400 Received: by mail-pl1-f196.google.com with SMTP id w3so9630367plz.5; Tue, 17 Mar 2020 06:25:32 -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=kvShCFneTqNWCShSIFRg6DQFBqujhrj5sjdHfCk9weg=; b=r6lEtRqdkojIaCRzqksEKRqICnthfZXUavxesNwoNyv3H6rjq75b5EUE9AKoh0MhBS 6vIFmOM73ladz7zHK1QecXEe4WqzlgEk40azox9L5gP10rqNuIQPqrQR7JQfSVl4NB4p j/KgRlWtwsbS8pae84BnC2RHoDTF0+7QNIu6L2qn01qtRtqP7WY+HzLP0QsMPiR4sDAk Lfa10fcI9uYuOgLrDvAuLyrZI6/jXq5rh6W1VMMhLFb0LKNtL1vUrTLHbCCePukZchkk PjNV5aD1iapF/p+z3AIbH5MR7VTaoKRY+06rIq/mjFLz58CQIBjN5bUuUTP9Mj56fSZD n1Pg== 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=kvShCFneTqNWCShSIFRg6DQFBqujhrj5sjdHfCk9weg=; b=kJ54M8ichXkjeP5TnBVI4NbdQxA+hXRG8M3Bv7xm53E8V3sYGQfU/VPXzn9lkqMWVY Bj16afPnq3KLsJ6kmzUikkGxt76u36NpA44HcB6aFz6MJhFb0rKPOqywgjyXqO35+Hu3 wWcES+0OEkjB1U+fTjxk+hq3vmNGMzeLol81Eezt9LxSn0PqZ3UCUUP7Uuj9zZVU46ui kzN4a+wvVyXJ/f1I6kFNy831CEQkFXY4FhRpXdC6Hl9/kViqGmfEQnn3MGu6/z+LVWjK BEB3B1xxy/zUxwVvqQ1zmwubO/jxAfeyVEYgsp/2LUeb+yX8UNj+nI2Ho9Ph5XJKYJHK qvWw== X-Gm-Message-State: ANhLgQ34lsbAhL3wqKtyrAw8EIViPCnc/6Oe2+bLu6l0daTKlbLoA/ko 2dAlbuNS/serRXu5oKltHl8= X-Google-Smtp-Source: ADFU+vteWXHd6n9nuJOFGQMBnhZ/il1kMyVw9aW2v4v52kZvfrF89ZHOa/PNnFOHez1jtvt8yhSkHQ== X-Received: by 2002:a17:902:b208:: with SMTP id t8mr4228476plr.94.1584451532323; Tue, 17 Mar 2020 06:25:32 -0700 (PDT) Received: from localhost.corp.microsoft.com ([167.220.2.210]) by smtp.googlemail.com with ESMTPSA id e30sm2910902pga.6.2020.03.17.06.25.31 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 17 Mar 2020 06:25:31 -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, michael.h.kelley@microsoft.com Cc: Tianyu Lan , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org, vkuznets@redhat.com Subject: [PATCH 3/4] x86/Hyper-V: Trigger crash enlightenment only once during system crash. Date: Tue, 17 Mar 2020 06:25:22 -0700 Message-Id: <20200317132523.1508-4-Tianyu.Lan@microsoft.com> X-Mailer: git-send-email 2.14.5 In-Reply-To: <20200317132523.1508-1-Tianyu.Lan@microsoft.com> References: <20200317132523.1508-1-Tianyu.Lan@microsoft.com> Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org From: Tianyu Lan Hyper-V expects guest only triggers crash enlightenment. The second crash notify will be ignored by Hyper-V. Current code may trigger crash enlightenment during system panic twice. 1) The enlightenment is triggered in hyperv_panic/die_event() via hyperv_report_panic(). 2) hv_kmsg_dump() reports kmsg to host via hyperv_report_panic_msg(). Fix it. If kmsg dump is registered successfully, just report kmsg via hyperv_report_panic_msg() and not report register values via hyperv_report_panic(). Signed-off-by: Tianyu Lan --- drivers/hv/vmbus_drv.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/hv/vmbus_drv.c b/drivers/hv/vmbus_drv.c index b043efea092a..1787d6246251 100644 --- a/drivers/hv/vmbus_drv.c +++ b/drivers/hv/vmbus_drv.c @@ -55,7 +55,12 @@ static int hyperv_panic_event(struct notifier_block *nb, unsigned long val, vmbus_initiate_unload(true); - if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE) { + /* + * Crash notify only can be triggered once. If crash notify + * message is available, just report kmsg to crash buffer. + */ + if (ms_hyperv.misc_features & HV_FEATURE_GUEST_CRASH_MSR_AVAILABLE + && !hv_panic_page) { regs = current_pt_regs(); hyperv_report_panic(regs, val); } @@ -68,7 +73,12 @@ static int hyperv_die_event(struct notifier_block *nb, unsigned long val, struct die_args *die = (struct die_args *)args; struct pt_regs *regs = die->regs; - hyperv_report_panic(regs, val); + /* + * Crash notify only can be triggered once. If crash notify + * message is available, just report kmsg to crash buffer. + */ + if (!hv_panic_page) + hyperv_report_panic(regs, val); return NOTIFY_DONE; } -- 2.14.5