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=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 9D045C433E1 for ; Tue, 28 Jul 2020 02:33:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7511B2075A for ; Tue, 28 Jul 2020 02:33:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="U+yPPzat" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726980AbgG1CdC (ORCPT ); Mon, 27 Jul 2020 22:33:02 -0400 Received: from us-smtp-2.mimecast.com ([207.211.31.81]:21939 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726541AbgG1CdB (ORCPT ); Mon, 27 Jul 2020 22:33:01 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1595903580; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=m2Dgok5d4kIn9F8q0n3JSRWupAQ4Bqg6yV879GUqY3s=; b=U+yPPzat2nnoFPkxRwAeN/jmpad9WrPGxs5nrMxPiJ2VlhBZ3sPLvZsmgeIEZGlQzBSwnQ 6Hd/XniV87pI4dkwH/8bRsyvdX8riyBn5uxzzHcpx0x10F2K+iuH0HLKSaMCpt+SNN4RIm TpZpbaI8p4n3PS/y8f5nX1+b6vPlAnY= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-31-9BMR-vUtOkSbC6hRJHCq1Q-1; Mon, 27 Jul 2020 22:32:58 -0400 X-MC-Unique: 9BMR-vUtOkSbC6hRJHCq1Q-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0FA4D800688; Tue, 28 Jul 2020 02:32:56 +0000 (UTC) Received: from [10.72.8.32] (ovpn-8-32.pek2.redhat.com [10.72.8.32]) by smtp.corp.redhat.com (Postfix) with ESMTPS id AC21A5F1EA; Tue, 28 Jul 2020 02:32:45 +0000 (UTC) Subject: Re: [RESEND PATCH v5 00/11] ppc64: enable kdump support for kexec_file_load syscall To: Hari Bathini , Michael Ellerman , Andrew Morton References: <159579157320.5790.6748078824637688685.stgit@hbathini> Cc: kernel test robot , Laurent Dufour , Dave Young , Thiago Jung Bauermann , Mahesh J Salgaonkar , Sourabh Jain , Vivek Goyal , Petr Tesarik , linuxppc-dev , Kexec-ml , lkml , Eric Biederman , Mimi Zohar , Nayna Jain From: piliu Message-ID: <23911b9d-7534-031c-6f98-80f90439c834@redhat.com> Date: Tue, 28 Jul 2020 10:32:42 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <159579157320.5790.6748078824637688685.stgit@hbathini> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/27/2020 03:36 AM, Hari Bathini wrote: > Sorry! There was a gateway issue on my system while posting v5, due to > which some patches did not make it through. Resending... > > This patch series enables kdump support for kexec_file_load system > call (kexec -s -p) on PPC64. The changes are inspired from kexec-tools > code but heavily modified for kernel consumption. > > The first patch adds a weak arch_kexec_locate_mem_hole() function to > override locate memory hole logic suiting arch needs. There are some > special regions in ppc64 which should be avoided while loading buffer > & there are multiple callers to kexec_add_buffer making it complicated > to maintain range sanity and using generic lookup at the same time. > > The second patch marks ppc64 specific code within arch/powerpc/kexec > and arch/powerpc/purgatory to make the subsequent code changes easy > to understand. > > The next patch adds helper function to setup different memory ranges > needed for loading kdump kernel, booting into it and exporting the > crashing kernel's elfcore. > > The fourth patch overrides arch_kexec_locate_mem_hole() function to > locate memory hole for kdump segments by accounting for the special > memory regions, referred to as excluded memory ranges, and sets > kbuf->mem when a suitable memory region is found. > > The fifth patch moves walk_drmem_lmbs() out of .init section with > a few changes to reuse it for setting up kdump kernel's usable memory > ranges. The next patch uses walk_drmem_lmbs() to look up the LMBs > and set linux,drconf-usable-memory & linux,usable-memory properties > in order to restrict kdump kernel's memory usage. > > The seventh patch updates purgatory to setup r8 & r9 with opal base > and opal entry addresses respectively to aid kernels built with > CONFIG_PPC_EARLY_DEBUG_OPAL enabled. The next patch setups up backup > region as a kexec segment while loading kdump kernel and teaches > purgatory to copy data from source to destination. > > Patch 09 builds the elfcore header for the running kernel & passes > the info to kdump kernel via "elfcorehdr=" parameter to export as > /proc/vmcore file. The next patch sets up the memory reserve map > for the kexec kernel and also claims kdump support for kdump as > all the necessary changes are added. > > The last patch fixes a lookup issue for `kexec -l -s` case when > memory is reserved for crashkernel. > > Tested the changes successfully on P8, P9 lpars, couple of OpenPOWER > boxes, one with secureboot enabled, KVM guest and a simulator. > > v4 -> v5: > * Dropped patches 07/12 & 08/12 and updated purgatory to do everything > in assembly. I guess you achieve this by carefully selecting instruction to avoid relocation issue, right? Thanks, Pingfan