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=-5.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 6B9C8C7114E for ; Wed, 19 Feb 2020 21:45:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3742924654 for ; Wed, 19 Feb 2020 21:45:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3742924654 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id C426E6B0008; Wed, 19 Feb 2020 16:45:19 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BA4E36B007B; Wed, 19 Feb 2020 16:45:19 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A93846B007D; Wed, 19 Feb 2020 16:45:19 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0050.hostedemail.com [216.40.44.50]) by kanga.kvack.org (Postfix) with ESMTP id 8EAFE6B0008 for ; Wed, 19 Feb 2020 16:45:19 -0500 (EST) Received: from smtpin26.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 519B28248047 for ; Wed, 19 Feb 2020 21:45:19 +0000 (UTC) X-FDA: 76508207958.26.skirt86_6893eef33da47 X-HE-Tag: skirt86_6893eef33da47 X-Filterd-Recvd-Size: 5213 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by imf31.hostedemail.com (Postfix) with ESMTP for ; Wed, 19 Feb 2020 21:45:18 +0000 (UTC) X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga106.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Feb 2020 13:45:16 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.70,462,1574150400"; d="scan'208";a="236022531" Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by orsmga003.jf.intel.com with ESMTP; 19 Feb 2020 13:45:14 -0800 Date: Thu, 20 Feb 2020 05:45:33 +0800 From: Wei Yang To: Andrew Morton Cc: Baoquan He , linux-kernel@vger.kernel.org, linux-mm@kvack.org, richardw.yang@linux.intel.com, david@redhat.com, osalvador@suse.de, dan.j.williams@intel.com, mhocko@suse.com Subject: Re: [PATCH v2 RESEND] mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM Message-ID: <20200219214533.GA20781@richard> Reply-To: Wei Yang References: <20200219030454.4844-1-bhe@redhat.com> <20200219115042.e8738272455292d3a6a6e498@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200219115042.e8738272455292d3a6a6e498@linux-foundation.org> User-Agent: Mutt/1.9.4 (2018-02-28) 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: On Wed, Feb 19, 2020 at 11:50:42AM -0800, Andrew Morton wrote: >On Wed, 19 Feb 2020 11:04:54 +0800 Baoquan He wrote: > >> From: Wei Yang >> >> When we use SPARSEMEM instead of SPARSEMEM_VMEMMAP, pfn_to_page() >> doesn't work before sparse_init_one_section() is called. This leads to a >> crash when hotplug memory: >> >> [ 41.839170] BUG: unable to handle page fault for address: 0000000006400000 >> [ 41.840663] #PF: supervisor write access in kernel mode >> [ 41.841822] #PF: error_code(0x0002) - not-present page >> [ 41.842970] PGD 0 P4D 0 >> [ 41.843538] Oops: 0002 [#1] SMP PTI >> [ 41.844125] CPU: 3 PID: 221 Comm: kworker/u16:1 Tainted: G W 5.5.0-next-20200205+ #343 >> [ 41.845659] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 >> [ 41.846977] Workqueue: kacpi_hotplug acpi_hotplug_work_fn >> [ 41.847904] RIP: 0010:__memset+0x24/0x30 >> [ 41.848660] Code: cc cc cc cc cc cc 0f 1f 44 00 00 49 89 f9 48 89 d1 83 e2 07 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 48 ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1 f3 >> [ 41.851836] RSP: 0018:ffffb43ac0373c80 EFLAGS: 00010a87 >> [ 41.852686] RAX: ffffffffffffffff RBX: ffff8a1518800000 RCX: 0000000000050000 >> [ 41.853824] RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000006400000 >> [ 41.854967] RBP: 0000000000140000 R08: 0000000000100000 R09: 0000000006400000 >> [ 41.856107] R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 >> [ 41.857255] R13: 0000000000000028 R14: 0000000000000000 R15: ffff8a153ffd9280 >> [ 41.858414] FS: 0000000000000000(0000) GS:ffff8a153ab00000(0000) knlGS:0000000000000000 >> [ 41.859703] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >> [ 41.860627] CR2: 0000000006400000 CR3: 0000000136fca000 CR4: 00000000000006e0 >> [ 41.861716] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >> [ 41.862680] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >> [ 41.863628] Call Trace: >> [ 41.863983] sparse_add_section+0x1c9/0x26a >> [ 41.864570] __add_pages+0xbf/0x150 >> [ 41.865057] add_pages+0x12/0x60 >> [ 41.865489] add_memory_resource+0xc8/0x210 >> [ 41.866017] ? wake_up_q+0xa0/0xa0 >> [ 41.866416] __add_memory+0x62/0xb0 >> [ 41.866825] acpi_memory_device_add+0x13f/0x300 >> [ 41.867410] acpi_bus_attach+0xf6/0x200 >> [ 41.867890] acpi_bus_scan+0x43/0x90 >> [ 41.868448] acpi_device_hotplug+0x275/0x3d0 >> [ 41.868972] acpi_hotplug_work_fn+0x1a/0x30 >> [ 41.869473] process_one_work+0x1a7/0x370 >> [ 41.869953] worker_thread+0x30/0x380 >> [ 41.870396] ? flush_rcu_work+0x30/0x30 >> [ 41.870846] kthread+0x112/0x130 >> [ 41.871236] ? kthread_create_on_node+0x60/0x60 >> [ 41.871770] ret_from_fork+0x35/0x40 >> >> We should use memmap as it did. >> >> Fixes: ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug") >> Signed-off-by: Wei Yang >> Acked-by: David Hildenbrand >> Reviewed-by: Baoquan He >> CC: Dan Williams > >This should have included your signed-off-by, as you were on the patch >delivery path. I have made that change to my copy of the patch - is >that OK? > >I also added a cc:stable. Do we agree this is appropriate? Agree with this. > >I added Dan's "On x86 the impact is limited to x86_32 builds, or x86_64 >configurations that override the default setting for >SPARSEMEM_VMEMMAP." to the changelog. -- Wei Yang Help you, Help me