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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 AB65CC10F27 for ; Sat, 7 Mar 2020 23:00:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 840692075E for ; Sat, 7 Mar 2020 23:00:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="Ul6nKurM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726340AbgCGWzl (ORCPT ); Sat, 7 Mar 2020 17:55:41 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:50029 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726138AbgCGWzl (ORCPT ); Sat, 7 Mar 2020 17:55:41 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1583621740; 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: in-reply-to:in-reply-to:references:references; bh=+rNcJxrVWwYcvfrtJi72ELJuI7ojNOfm3cddFv7e+dQ=; b=Ul6nKurMi9IlyalxVpsqiyvjttNNRN+9cU7YeZuBcsc5f8Csh5XEVsuciq64x+PJribIbc W2vIEldXsELAyQ7UZgCTsRCyhpZCFf+015IhD8J2xOtlKHPt0b9FNIAt7XTbdYtdF0zsGp wHvDdplguxHrUxRSv1tkQpMBxN9HlUs= 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-336-DtkrUQVTPsmsn-r1jFnqeg-1; Sat, 07 Mar 2020 17:55:38 -0500 X-MC-Unique: DtkrUQVTPsmsn-r1jFnqeg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AE95D477; Sat, 7 Mar 2020 22:55:36 +0000 (UTC) Received: from localhost (ovpn-12-26.pek2.redhat.com [10.72.12.26]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 28CD146; Sat, 7 Mar 2020 22:55:32 +0000 (UTC) Date: Sun, 8 Mar 2020 06:55:30 +0800 From: Baoquan He To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, mhocko@suse.com, david@redhat.com, richardw.yang@linux.intel.com, dan.j.williams@intel.com, osalvador@suse.de, rppt@linux.ibm.com Subject: Re: [PATCH v3 1/7] mm/hotplug: fix hot remove failure in SPARSEMEM|!VMEMMAP case Message-ID: <20200307225530.GC27711@MiWiFi-R3L-srv> References: <20200307084229.28251-1-bhe@redhat.com> <20200307084229.28251-2-bhe@redhat.com> <20200307125931.8e75709181f5c4bda40b1ee5@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200307125931.8e75709181f5c4bda40b1ee5@linux-foundation.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/07/20 at 12:59pm, Andrew Morton wrote: > On Sat, 7 Mar 2020 16:42:23 +0800 Baoquan He wrote: > > > In section_deactivate(), pfn_to_page() doesn't work any more after > > ms->section_mem_map is resetting to NULL in SPARSEMEM|!VMEMMAP case. > > It caused hot remove failure: > > > > kernel BUG at mm/page_alloc.c:4806! > > invalid opcode: 0000 [#1] SMP PTI > > CPU: 3 PID: 8 Comm: kworker/u16:0 Tainted: G W 5.5.0-next-20200205+ #340 > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 > > Workqueue: kacpi_hotplug acpi_hotplug_work_fn > > RIP: 0010:free_pages+0x85/0xa0 > > Call Trace: > > __remove_pages+0x99/0xc0 > > arch_remove_memory+0x23/0x4d > > try_remove_memory+0xc8/0x130 > > ? walk_memory_blocks+0x72/0xa0 > > __remove_memory+0xa/0x11 > > acpi_memory_device_remove+0x72/0x100 > > acpi_bus_trim+0x55/0x90 > > acpi_device_hotplug+0x2eb/0x3d0 > > acpi_hotplug_work_fn+0x1a/0x30 > > process_one_work+0x1a7/0x370 > > worker_thread+0x30/0x380 > > ? flush_rcu_work+0x30/0x30 > > kthread+0x112/0x130 > > ? kthread_create_on_node+0x60/0x60 > > ret_from_fork+0x35/0x40 > > > > Let's move the ->section_mem_map resetting after depopulate_section_memmap() > > to fix it. > > Thanks. I think I'll cherrypick this fix and shall await more > review/testing input on the rest of the series. Sure, thanks.