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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 416C4C48BDF for ; Wed, 16 Jun 2021 01:23:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2A7246137D for ; Wed, 16 Jun 2021 01:23:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231840AbhFPBZj (ORCPT ); Tue, 15 Jun 2021 21:25:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:39974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231835AbhFPBZj (ORCPT ); Tue, 15 Jun 2021 21:25:39 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2F71861356; Wed, 16 Jun 2021 01:23:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1623806613; bh=5vvt6dQdqnMn/3BBdU1MAi2Tx/HWOlAus5gQOe/kOzk=; h=Date:From:To:Subject:In-Reply-To:From; b=evOYMYHXYKi+i48c5dsWTJ3ni9YkSpYksM8CaCSOGOUTFO+CErKsr4FndzJNJtG+q 94JuIs8bj5z+6Kko5Vl8T72wHRLey8yh784TS53dT7CIbilqvN060vSUGFVkzUcSNZ tfVrpI5FXc8PMG10wuH13CdYx0/dYb4e0uzrYwuc= Date: Tue, 15 Jun 2021 18:23:32 -0700 From: Andrew Morton To: akpm@linux-foundation.org, jack@suse.cz, linux-mm@kvack.org, mm-commits@vger.kernel.org, naoya.horiguchi@nec.com, osalvador@suse.de, torvalds@linux-foundation.org, tytso@mit.edu, yangerkun@huawei.com, yukuai3@huawei.com Subject: [patch 07/18] mm/memory-failure: make sure wait for page writeback in memory_failure Message-ID: <20210616012332.bPPCzBRm4%akpm@linux-foundation.org> In-Reply-To: <20210615182248.9a0ba90e8e66b9f4a53c0d23@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: yangerkun Subject: mm/memory-failure: make sure wait for page writeback in memory_failure Our syzkaller trigger the "BUG_ON(!list_empty(&inode->i_wb_list))" in clear_inode: [ 292.016156] ------------[ cut here ]------------ [ 292.017144] kernel BUG at fs/inode.c:519! [ 292.017860] Internal error: Oops - BUG: 0 [#1] SMP [ 292.018741] Dumping ftrace buffer: [ 292.019577] (ftrace buffer empty) [ 292.020430] Modules linked in: [ 292.021748] Process syz-executor.0 (pid: 249, stack limit = 0x00000000a12409d7) [ 292.023719] CPU: 1 PID: 249 Comm: syz-executor.0 Not tainted 4.19.95 [ 292.025206] Hardware name: linux,dummy-virt (DT) [ 292.026176] pstate: 80000005 (Nzcv daif -PAN -UAO) [ 292.027244] pc : clear_inode+0x280/0x2a8 [ 292.028045] lr : clear_inode+0x280/0x2a8 [ 292.028877] sp : ffff8003366c7950 [ 292.029582] x29: ffff8003366c7950 x28: 0000000000000000 [ 292.030570] x27: ffff80032b5f4708 x26: ffff80032b5f4678 [ 292.031863] x25: ffff80036ae6b300 x24: ffff8003689254d0 [ 292.032902] x23: ffff80036ae69d80 x22: 0000000000033cc8 [ 292.033928] x21: 0000000000000000 x20: ffff80032b5f47a0 [ 292.034941] x19: ffff80032b5f4678 x18: 0000000000000000 [ 292.035958] x17: 0000000000000000 x16: 0000000000000000 [ 292.037102] x15: 0000000000000000 x14: 0000000000000000 [ 292.038103] x13: 0000000000000004 x12: 0000000000000000 [ 292.039137] x11: 1ffff00066cd8f52 x10: 1ffff00066cd8ec8 [ 292.040216] x9 : dfff200000000000 x8 : ffff10006ac1e86a [ 292.041432] x7 : dfff200000000000 x6 : ffff100066cd8f1e [ 292.042516] x5 : dfff200000000000 x4 : ffff80032b5f47a0 [ 292.043525] x3 : ffff200008000000 x2 : ffff200009867000 [ 292.044560] x1 : ffff8003366bb000 x0 : 0000000000000000 [ 292.045569] Call trace: [ 292.046083] clear_inode+0x280/0x2a8 [ 292.046828] ext4_clear_inode+0x38/0xe8 [ 292.047593] ext4_free_inode+0x130/0xc68 [ 292.048383] ext4_evict_inode+0xb20/0xcb8 [ 292.049162] evict+0x1a8/0x3c0 [ 292.049761] iput+0x344/0x460 [ 292.050350] do_unlinkat+0x260/0x410 [ 292.051042] __arm64_sys_unlinkat+0x6c/0xc0 [ 292.051846] el0_svc_common+0xdc/0x3b0 [ 292.052570] el0_svc_handler+0xf8/0x160 [ 292.053303] el0_svc+0x10/0x218 [ 292.053908] Code: 9413f4a9 d503201f f90017b6 97f4d5b1 (d4210000) [ 292.055471] ---[ end trace 01b339dd07795f8d ]--- [ 292.056443] Kernel panic - not syncing: Fatal exception [ 292.057488] SMP: stopping secondary CPUs [ 292.058419] Dumping ftrace buffer: [ 292.059078] (ftrace buffer empty) [ 292.059756] Kernel Offset: disabled [ 292.060443] CPU features: 0x10,a1006000 [ 292.061195] Memory Limit: none [ 292.061794] Rebooting in 86400 seconds.. Crash of this problem show that someone call __munlock_pagevec to clear page LRU without lock_page. #0 [ffff80035f02f4c0] __switch_to at ffff20000808d020 #1 [ffff80035f02f4f0] __schedule at ffff20000985102c #2 [ffff80035f02f5e0] schedule at ffff200009851d1c #3 [ffff80035f02f600] io_schedule at ffff2000098525c0 #4 [ffff80035f02f620] __lock_page at ffff20000842d2d4 #5 [ffff80035f02f710] __munlock_pagevec at ffff2000084c4600 #6 [ffff80035f02f870] munlock_vma_pages_range at ffff2000084c5928 #7 [ffff80035f02fa60] do_munmap at ffff2000084cbdf4 #8 [ffff80035f02faf0] mmap_region at ffff2000084ce20c #9 [ffff80035f02fb90] do_mmap at ffff2000084cf018 So memory_failure will call identify_page_state without wait_on_page_writeback. And after truncate_error_page clear the mapping of this page. end_page_writeback won't call sb_clear_inode_writeback to clear inode->i_wb_list. That will trigger BUG_ON in clear_inode! Fix it by checking PageWriteback too to help determine should we skip wait_on_page_writeback. Link: https://lkml.kernel.org/r/20210604084705.3729204-1-yangerkun@huawei.com Fixes: 0bc1f8b0682c ("hwpoison: fix the handling path of the victimized page frame that belong to non-LRU") Signed-off-by: yangerkun Acked-by: Naoya Horiguchi Cc: Jan Kara Cc: Theodore Ts'o Cc: Oscar Salvador Cc: Yu Kuai Signed-off-by: Andrew Morton --- mm/memory-failure.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) --- a/mm/memory-failure.c~mm-memory-failure-make-sure-wait-for-page-writeback-in-memory_failure +++ a/mm/memory-failure.c @@ -1552,7 +1552,12 @@ try_again: return 0; } - if (!PageTransTail(p) && !PageLRU(p)) + /* + * __munlock_pagevec may clear a writeback page's LRU flag without + * page_lock. We need wait writeback completion for this page or it + * may trigger vfs BUG while evict inode. + */ + if (!PageTransTail(p) && !PageLRU(p) && !PageWriteback(p)) goto identify_page_state; /* _