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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 AB097C3F369 for ; Thu, 27 Feb 2020 14:15:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 82A1424691 for ; Thu, 27 Feb 2020 14:15:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582812950; bh=54BZhhHTvezPRnYlAHI41UMVku5HZBj5re7OJNW61D0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=m+KXm5hhVMaXw/HsatBCgcOLEcaXTcySKTXLiYLT0dz5BOt0CxA7L3OXYBE5qkt51 /xz37WK5yEQphezIXSxXmugQnqigkNrCKh4P2K6TSqpTBg9FeTf36EMCkMGViCvcjT rH9DkB+5s42T8hFddnaA7Q/GYGWjSFCsXkWH9Qmo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389366AbgB0OPt (ORCPT ); Thu, 27 Feb 2020 09:15:49 -0500 Received: from mail.kernel.org ([198.145.29.99]:55422 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389352AbgB0OPp (ORCPT ); Thu, 27 Feb 2020 09:15:45 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 86570246A0; Thu, 27 Feb 2020 14:15:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582812945; bh=54BZhhHTvezPRnYlAHI41UMVku5HZBj5re7OJNW61D0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MQ4sk5eACSm1Y4m+7bw86DLJwn+SVK/lDGbxfSPg0/wTb9EvUZfPFV88HtSYUL3i6 SUDpyJ7j+826YjQ+0mlSB31IaCgumlS1OcdFmRvbmdbDXhafgcnJchuuq+ClPTQusM 2SM2K9DiwMeVwFuaukMaw1dUdAsZ2PswogFZKebA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wei Yang , Baoquan He , David Hildenbrand , Dan Williams , Michal Hocko , Mike Rapoport , Oscar Salvador , Andrew Morton , Linus Torvalds Subject: [PATCH 5.5 077/150] mm/sparsemem: pfn_to_page is not valid yet on SPARSEMEM Date: Thu, 27 Feb 2020 14:36:54 +0100 Message-Id: <20200227132244.212362604@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200227132232.815448360@linuxfoundation.org> References: <20200227132232.815448360@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Wei Yang commit 18e19f195cd888f65643a77a0c6aee8f5be6439a upstream. 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: BUG: unable to handle page fault for address: 0000000006400000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP PTI CPU: 3 PID: 221 Comm: kworker/u16:1 Tainted: G W 5.5.0-next-20200205+ #343 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 Workqueue: kacpi_hotplug acpi_hotplug_work_fn RIP: 0010:__memset+0x24/0x30 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 RSP: 0018:ffffb43ac0373c80 EFLAGS: 00010a87 RAX: ffffffffffffffff RBX: ffff8a1518800000 RCX: 0000000000050000 RDX: 0000000000000000 RSI: 00000000000000ff RDI: 0000000006400000 RBP: 0000000000140000 R08: 0000000000100000 R09: 0000000006400000 R10: 0000000000000000 R11: 0000000000000002 R12: 0000000000000000 R13: 0000000000000028 R14: 0000000000000000 R15: ffff8a153ffd9280 FS: 0000000000000000(0000) GS:ffff8a153ab00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000006400000 CR3: 0000000136fca000 CR4: 00000000000006e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sparse_add_section+0x1c9/0x26a __add_pages+0xbf/0x150 add_pages+0x12/0x60 add_memory_resource+0xc8/0x210 __add_memory+0x62/0xb0 acpi_memory_device_add+0x13f/0x300 acpi_bus_attach+0xf6/0x200 acpi_bus_scan+0x43/0x90 acpi_device_hotplug+0x275/0x3d0 acpi_hotplug_work_fn+0x1a/0x30 process_one_work+0x1a7/0x370 worker_thread+0x30/0x380 kthread+0x112/0x130 ret_from_fork+0x35/0x40 We should use memmap as it did. On x86 the impact is limited to x86_32 builds, or x86_64 configurations that override the default setting for SPARSEMEM_VMEMMAP. Other memory hotplug archs (arm64, ia64, and ppc) also default to SPARSEMEM_VMEMMAP=y. [dan.j.williams@intel.com: changelog update] {rppt@linux.ibm.com: changelog update] Link: http://lkml.kernel.org/r/20200219030454.4844-1-bhe@redhat.com Fixes: ba72b4c8cf60 ("mm/sparsemem: support sub-section hotplug") Signed-off-by: Wei Yang Signed-off-by: Baoquan He Acked-by: David Hildenbrand Reviewed-by: Baoquan He Reviewed-by: Dan Williams Acked-by: Michal Hocko Cc: Mike Rapoport Cc: Oscar Salvador Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/sparse.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/sparse.c +++ b/mm/sparse.c @@ -886,7 +886,7 @@ int __meminit sparse_add_section(int nid * Poison uninitialized struct pages in order to catch invalid flags * combinations. */ - page_init_poison(pfn_to_page(start_pfn), sizeof(struct page) * nr_pages); + page_init_poison(memmap, sizeof(struct page) * nr_pages); ms = __nr_to_section(section_nr); set_section_nid(section_nr, nid);