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=-8.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 5114AC5CFFE for ; Tue, 11 Dec 2018 08:46:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1EA1C2081B for ; Tue, 11 Dec 2018 08:46:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1EA1C2081B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726239AbeLKIqY (ORCPT ); Tue, 11 Dec 2018 03:46:24 -0500 Received: from mga01.intel.com ([192.55.52.88]:1765 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726085AbeLKIqW (ORCPT ); Tue, 11 Dec 2018 03:46:22 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Dec 2018 00:46:18 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,341,1539673200"; d="scan'208";a="106520746" Received: from yhuang-mobile.sh.intel.com ([10.239.192.61]) by fmsmga007.fm.intel.com with ESMTP; 11 Dec 2018 00:46:16 -0800 From: Huang Ying To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Huang Ying , Vineeth Remanan Pillai , Kelley Nielsen , Rik van Riel , Matthew Wilcox , Hugh Dickins Subject: [PATCH 1/2] swap: Fix general protection fault when swapoff Date: Tue, 11 Dec 2018 16:46:08 +0800 Message-Id: <20181211084609.19553-1-ying.huang@intel.com> X-Mailer: git-send-email 2.18.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When VMA based swap readahead is used, which is default if all swap devices are SSD, swapoff will trigger general protection fault as follow, because vmf->pmd isn't initialized when calling swapin_readahead(). This fix could be folded into the patch: mm, swap: rid swapoff of quadratic complexity in -mm patchset. general protection fault: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC CPU: 3 PID: 352 Comm: swapoff Not tainted 4.20.0-rc5-mm1-kvm+ #535 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-1.fc28 04/01/2014 RIP: 0010:swapin_readahead+0xb7/0x39b Code: ff 01 00 00 40 f6 c7 80 49 0f 45 d0 48 21 d7 48 ba 00 00 00 00 80 88 ff ff 48 8d 14 f2 48 01 d7 48 ba ff ff ff ff ff ff ff ef <48> 39 17 0f 87 5d 01 00 00 49 8b 95 b0 00 00 00 48 85 d2 75 05 ba RSP: 0018:ffffc900004c3ca0 EFLAGS: 00010207 RAX: 000055de5d252000 RBX: 000000055de5d252 RCX: 0000000000000003 RDX: efffffffffffffff RSI: 0000000000000052 RDI: 000f0bc11c600290 RBP: ffffc900004c3d30 R08: 000fffffffe00000 R09: ffffc900004c3ea0 R10: ffffc900004c3d50 R11: 0000000000000002 R12: ffffc900004c3da8 R13: ffff88803b71d780 R14: 0000000000000001 R15: ffff88803b71d780 FS: 00007f87c20e02c0(0000) GS:ffff88803e800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055a439825398 CR3: 000000003b49a004 CR4: 0000000000360ea0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? list_add_tail_rcu+0x19/0x31 ? __lock_acquire+0xd61/0xe1c ? find_held_lock+0x2b/0x6e ? unuse_pte_range+0xe9/0x429 unuse_pte_range+0xe9/0x429 ? find_held_lock+0x2b/0x6e ? __lock_is_held+0x40/0x71 try_to_unuse+0x311/0x54b __do_sys_swapoff+0x254/0x625 ? lockdep_hardirqs_off+0x29/0x86 ? do_syscall_64+0x12/0x65 do_syscall_64+0x57/0x65 entry_SYSCALL_64_after_hwframe+0x49/0xbe Signed-off-by: "Huang, Ying" Cc: Vineeth Remanan Pillai Cc: Kelley Nielsen Cc: Rik van Riel Cc: Matthew Wilcox Cc: Hugh Dickins --- mm/swapfile.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/swapfile.c b/mm/swapfile.c index 9ca162cc45dc..7464d0a92869 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1904,6 +1904,7 @@ static int unuse_pte_range(struct vm_area_struct *vma, pmd_t *pmd, swap_map = &si->swap_map[offset]; vmf.vma = vma; vmf.address = addr; + vmf.pmd = pmd; page = swapin_readahead(entry, GFP_HIGHUSER_MOVABLE, &vmf); if (!page) { if (*swap_map == 0 || *swap_map == SWAP_MAP_BAD) -- 2.18.1