From patchwork Sat Mar 7 08:42:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Baoquan He X-Patchwork-Id: 11425135 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 116E914E3 for ; Sat, 7 Mar 2020 08:42:49 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D23952073D for ; Sat, 7 Mar 2020 08:42:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="JdI+1YVf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D23952073D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 010456B0006; Sat, 7 Mar 2020 03:42:48 -0500 (EST) Delivered-To: linux-mm-outgoing@kvack.org Received: by kanga.kvack.org (Postfix, from userid 40) id F2E7B6B0007; Sat, 7 Mar 2020 03:42:47 -0500 (EST) X-Original-To: int-list-linux-mm@kvack.org X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E41D46B0008; Sat, 7 Mar 2020 03:42:47 -0500 (EST) X-Original-To: linux-mm@kvack.org X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0099.hostedemail.com [216.40.44.99]) by kanga.kvack.org (Postfix) with ESMTP id C9A646B0006 for ; Sat, 7 Mar 2020 03:42:47 -0500 (EST) Received: from smtpin09.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 6BDC52484 for ; Sat, 7 Mar 2020 08:42:47 +0000 (UTC) X-FDA: 76567925574.09.cord69_52871b5a45e5e X-Spam-Summary: 1,0,0,,d41d8cd98f00b204,bhe@redhat.com,,RULES_HIT:30029:30054:30056,0,RBL:207.211.31.120:@redhat.com:.lbl8.mailshell.net-66.10.201.10 62.18.0.100,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:ft,MSBL:0,DNSBL:neutral,Custom_rules:0:0:0,LFtime:24,LUA_SUMMARY:none X-HE-Tag: cord69_52871b5a45e5e X-Filterd-Recvd-Size: 4748 Received: from us-smtp-1.mimecast.com (us-smtp-delivery-1.mimecast.com [207.211.31.120]) by imf11.hostedemail.com (Postfix) with ESMTP for ; Sat, 7 Mar 2020 08:42:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1583570566; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:in-reply-to:in-reply-to:references:references; bh=UraJ83HV2pn1X1NXn9FVFonewL2jW9cZzbayED9iRfE=; b=JdI+1YVfvICT+s9V3Cx0340l1oX/ntkG6LxWFyqFoNVO/d49d56Cd4D9wyC0rtvNttEkCo /BdyiBkDdr3XvHuUlzi+OZaFHOvWftJ+c9sKYtF5H1g8FlP3zBNrTHDYAs9JQALNOUWRTB 5BcKwsq0Jzawc97TnJ+ZUYBd2UWyAwI= 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-223-lQgXJX1vNaCwwzLzbAGmqw-1; Sat, 07 Mar 2020 03:42:42 -0500 X-MC-Unique: lQgXJX1vNaCwwzLzbAGmqw-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 4D88B13EA; Sat, 7 Mar 2020 08:42:41 +0000 (UTC) Received: from MiWiFi-R3L-srv.redhat.com (ovpn-12-29.pek2.redhat.com [10.72.12.29]) by smtp.corp.redhat.com (Postfix) with ESMTP id 143B95D9CA; Sat, 7 Mar 2020 08:42:37 +0000 (UTC) From: Baoquan He To: linux-kernel@vger.kernel.org Cc: linux-mm@kvack.org, akpm@linux-foundation.org, mhocko@suse.com, david@redhat.com, richardw.yang@linux.intel.com, dan.j.williams@intel.com, osalvador@suse.de, rppt@linux.ibm.com, bhe@redhat.com Subject: [PATCH v3 1/7] mm/hotplug: fix hot remove failure in SPARSEMEM|!VMEMMAP case Date: Sat, 7 Mar 2020 16:42:23 +0800 Message-Id: <20200307084229.28251-2-bhe@redhat.com> In-Reply-To: <20200307084229.28251-1-bhe@redhat.com> References: <20200307084229.28251-1-bhe@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 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. Fixes: ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug") Signed-off-by: Baoquan He Cc: stable@vger.kernel.org Reviewed-by: David Hildenbrand Reviewed-by: Pankaj Gupta Acked-by: Michal Hocko --- mm/sparse.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/mm/sparse.c b/mm/sparse.c index 42c18a38ffaa..1b50c15677d7 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -734,6 +734,7 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages, struct mem_section *ms = __pfn_to_section(pfn); bool section_is_early = early_section(ms); struct page *memmap = NULL; + bool empty = false; unsigned long *subsection_map = ms->usage ? &ms->usage->subsection_map[0] : NULL; @@ -764,7 +765,8 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages, * For 2/ and 3/ the SPARSEMEM_VMEMMAP={y,n} cases are unified */ bitmap_xor(subsection_map, map, subsection_map, SUBSECTIONS_PER_SECTION); - if (bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION)) { + empty = bitmap_empty(subsection_map, SUBSECTIONS_PER_SECTION); + if (empty) { unsigned long section_nr = pfn_to_section_nr(pfn); /* @@ -779,13 +781,15 @@ static void section_deactivate(unsigned long pfn, unsigned long nr_pages, ms->usage = NULL; } memmap = sparse_decode_mem_map(ms->section_mem_map, section_nr); - ms->section_mem_map = (unsigned long)NULL; } if (section_is_early && memmap) free_map_bootmem(memmap); else depopulate_section_memmap(pfn, nr_pages, altmap); + + if (empty) + ms->section_mem_map = (unsigned long)NULL; } static struct page * __meminit section_activate(int nid, unsigned long pfn,