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=-3.7 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 BF294C34056 for ; Wed, 19 Feb 2020 20:13:46 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7A2232064C for ; Wed, 19 Feb 2020 20:13:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=intel-com.20150623.gappssmtp.com header.i=@intel-com.20150623.gappssmtp.com header.b="IRi5B/1J" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7A2232064C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 02C3E6B0003; Wed, 19 Feb 2020 15:13:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id F1EA86B0006; Wed, 19 Feb 2020 15:13:45 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E34306B0007; Wed, 19 Feb 2020 15:13:45 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0137.hostedemail.com [216.40.44.137]) by kanga.kvack.org (Postfix) with ESMTP id CCCAF6B0003 for ; Wed, 19 Feb 2020 15:13:45 -0500 (EST) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 8AB06282D for ; Wed, 19 Feb 2020 20:13:45 +0000 (UTC) X-FDA: 76507977210.14.gate19_20bc64901f653 X-HE-Tag: gate19_20bc64901f653 X-Filterd-Recvd-Size: 6773 Received: from mail-oi1-f196.google.com (mail-oi1-f196.google.com [209.85.167.196]) by imf21.hostedemail.com (Postfix) with ESMTP for ; Wed, 19 Feb 2020 20:13:44 +0000 (UTC) Received: by mail-oi1-f196.google.com with SMTP id q81so25163300oig.0 for ; Wed, 19 Feb 2020 12:13:44 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ltezjsG9cSeHNkUm3cauVbVZTwpvmoNXDjvuDFet2sM=; b=IRi5B/1JkjrG8O+hgNdmDfNuMqa+TLAAJAPTdn6sDCzd28nD/4BBjrY0jpwcB69pnA amzDXtf4MgDL9f34kLbb+Nzl57smWOCOTQ670TdWKaYV42bTviKJf0Xj6GJC4PD6pkQF Bd1ktnFHc/nM5S1iG8rVM9lTxtRzh5o9Ji0ol9iexX5IDZRpYX8hJUnZkT70JtGtOtIO eQoiVJQMJHa26koYZa8tN/oygTuDjKGSsyWe2Mio+Th+yKTOMg35CIVZPg5SD8jAp40P 2AopbEDYMWC4cj6a3QpDnxLMv1wVEy2IevIoxT0MeICHbu2fhR4o/9sqYf1A1JgXX7Gw ef+w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=ltezjsG9cSeHNkUm3cauVbVZTwpvmoNXDjvuDFet2sM=; b=pL4JBxxUY+2YrZ4a1j+OQ4l1A9Uo9rK5g8oryZGBlTl7mcaCk3xdhvpViksdmKZx2Y 72lqjRXbx0NuRwANgYjUV+wYmpPxJ9FFdMjMStUsF88JgROkLQAFoA0jvW0AQKS3UrzN xY8JIZa5eSou1ccQDR21/ooVl76QTe5RbV2+sVA3TjjZNi7p4zho9CHHamHJtG0ULNGI +q59yXzaqDyOWU/qRBsPpiBkwiJDXrsJPcqsbEViVcFvlUohfQDiW9lAKl8aWkOOV2aA 1ED3oOdMrpQeZDdLgqAux62MQBAwvtLde2AR/rfM9JpBgTIpxYchYBalxGCjI7IWtL2M /nWg== X-Gm-Message-State: APjAAAXhjhYz3JRiQkLgKYJH46gGZ16c/wUtV0wJW5d/lO2Cz36fNOXl 3WaqeioH1kHk6BH63MX6C3H+B7MpE2r1tJSxERrrRg== X-Google-Smtp-Source: APXvYqz4NhWRoo1EICJU8OdpnN9pDE7X7qZnDKtFmnO6vC/1zk0OTCtrIIArbc3e3Go1vVD3JLgrDRR4zg7rIkxKLmc= X-Received: by 2002:a05:6808:a83:: with SMTP id q3mr6146041oij.0.1582143224013; Wed, 19 Feb 2020 12:13:44 -0800 (PST) MIME-Version: 1.0 References: <20200219030454.4844-1-bhe@redhat.com> <20200219115042.e8738272455292d3a6a6e498@linux-foundation.org> In-Reply-To: <20200219115042.e8738272455292d3a6a6e498@linux-foundation.org> From: Dan Williams Date: Wed, 19 Feb 2020 12:13:33 -0800 Message-ID: Subject: Re: [PATCH v2 RESEND] mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM To: Andrew Morton Cc: Baoquan He , Linux Kernel Mailing List , Linux MM , Wei Yang , David Hildenbrand , Oscar Salvador , Michal Hocko Content-Type: text/plain; charset="UTF-8" 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 AM 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? I see no harm. > 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. Can also add with Mike's sleuthing. "Other memory hotplug archs (arm64, ia64, and ppc) also default to SPARSEMEM_VMEMMAP=y."