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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT 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 C5E4DC28CC5 for ; Sat, 8 Jun 2019 10:27:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B50A214AE for ; Sat, 8 Jun 2019 10:27:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726862AbfFHK1G (ORCPT ); Sat, 8 Jun 2019 06:27:06 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44706 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726692AbfFHK1G (ORCPT ); Sat, 8 Jun 2019 06:27:06 -0400 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 9D6C8368E6; Sat, 8 Jun 2019 10:27:05 +0000 (UTC) Received: from localhost (ovpn-12-31.pek2.redhat.com [10.72.12.31]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 39E4360589; Sat, 8 Jun 2019 10:27:01 +0000 (UTC) Date: Sat, 8 Jun 2019 18:26:59 +0800 From: Baoquan He To: Borislav Petkov Cc: lijiang , linux-kernel@vger.kernel.org, kexec@lists.infradead.org, tglx@linutronix.de, mingo@redhat.com, akpm@linux-foundation.org, dave.hansen@linux.intel.com, luto@kernel.org, peterz@infradead.org, x86@kernel.org, hpa@zytor.com, dyoung@redhat.com, Thomas.Lendacky@amd.com Subject: Re: [PATCH 0/3 v11] add reserved e820 ranges to the kdump kernel e820 table Message-ID: <20190608102659.GA9130@MiWiFi-R3L-srv> References: <20190423013007.17838-1-lijiang@redhat.com> <12847a03-3226-0b29-97b5-04d404410147@redhat.com> <20190607174211.GN20269@zn.tnic> <20190608035451.GB26148@MiWiFi-R3L-srv> <20190608091030.GB32464@zn.tnic> <20190608100139.GC26148@MiWiFi-R3L-srv> <20190608100623.GA9138@zn.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190608100623.GA9138@zn.tnic> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.30]); Sat, 08 Jun 2019 10:27:05 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/08/19 at 12:06pm, Borislav Petkov wrote: > On Sat, Jun 08, 2019 at 06:01:39PM +0800, Baoquan He wrote: > > OK, it may be different with the case we met, if panic happened when > > load a kdump kernel. > > > > We can load with 'kexec -l' or 'kexec -p', but can't boot after triggering > > crash or execute 'kexec -e' to do kexec jumping. > > No, I load a kdump kernel properly with this command: > > kexec -s -p /boot/vmlinuz-5.2.0-rc3+ --initrd=/boot/initrd.img-5.2.0-rc3+ --command-line="maxcpus=1 root=/dev/sda5 ro debug ignore_loglevel > log_buf_len=16M no_console_suspend net.ifnames=0 systemd.log_target=null mem_encrypt=on kvm_amd.sev=1 nr_cpus=1 irqpoll reset_devices vga=normal > LANG=en_US.UTF-8 earlyprintk=serial cgroup_disable=memory mce=off numa=off udev.children-max=2 panic=10 rootflags=nofail acpi_no_memhotplug > transparent_hugepage=never disable_cpu_apicid=0" > > And that succeeds judging from > > $ grep . /sys/kernel/kexec_* > > Then I trigger a panic with > > echo c > /proc/sysrq-trigger > > and this is where it hangs and doesn't load the kdump kernel. OK, I see. Then it should be the issue we have met and talked about with Tom. https://lkml.kernel.org/r/20190604134952.GC26891@MiWiFi-R3L-srv You can apply Tom's patch as below. I tested it, it can make kexec kernel succeed to boot, but failed for kdump kernel booting. The kdump kernel can boot till the end of kernel initialization, then hang with a call trace. I have pasted the log in the above thread. Haven't got the reason. http://lkml.kernel.org/r/508c2853-dc4f-70a6-6fa8-97c950dc31c6@amd.com