KCSAN: data-race in __xa_clear_mark / find_get_pages_range

KCSAN: data-race in __xa_clear_mark / find_get_pages_range_tag
Status: moderation: reported on 2020/07/01 11:02
Reported-by: syzbot+ef472c87cd23676ef6fe@syzkaller.appspotmail.com
First crash: 124d, last: 8h54m

Sample crash report:

==================================================================
BUG: KCSAN: data-race in __xa_clear_mark / find_get_pages_range_tag

write to 0xffff88800a5e88f0 of 8 bytes by interrupt on cpu 0:
 instrument_write include/linux/instrumented.h:42 [inline]
 __instrument_read_write_bitop include/asm-generic/bitops/instrumented-non-atomic.h:79 [inline]
 __test_and_clear_bit include/asm-generic/bitops/instrumented-non-atomic.h:109 [inline]
 node_clear_mark lib/xarray.c:100 [inline]
 xas_clear_mark lib/xarray.c:911 [inline]
 __xa_clear_mark+0xff/0x1e0 lib/xarray.c:1916
 test_clear_page_writeback+0x28d/0x480 mm/page-writeback.c:2739
 end_page_writeback+0xa7/0x110 mm/filemap.c:1487
 page_endio+0x1be/0x200 mm/filemap.c:1518
 mpage_end_io+0x186/0x1d0 fs/mpage.c:54
 bio_endio+0x28b/0x350 block/bio.c:1447
 req_bio_endio block/blk-core.c:259 [inline]
 blk_update_request+0x515/0xb40 block/blk-core.c:1463
 blk_mq_end_request+0x22/0x50 block/blk-mq.c:562
 lo_complete_rq+0xca/0x180 drivers/block/loop.c:500
 blk_done_softirq+0x1a5/0x200 block/blk-mq.c:586
 __do_softirq+0x198/0x331 kernel/softirq.c:298
 run_ksoftirqd+0x2f/0x60 kernel/softirq.c:653
 smpboot_thread_fn+0x347/0x530 kernel/smpboot.c:165
 kthread+0x1ff/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

read to 0xffff88800a5e88f0 of 8 bytes by task 8723 on cpu 1:
 xas_find_chunk include/linux/xarray.h:1660 [inline]
 xas_next_marked include/linux/xarray.h:1691 [inline]
 find_get_pages_range_tag+0x35c/0x600 mm/filemap.c:2094
 pagevec_lookup_range_tag+0x37/0x50 mm/swap.c:1161
 __filemap_fdatawait_range mm/filemap.c:519 [inline]
 filemap_fdatawait_keep_errors+0x7a/0x1e0 mm/filemap.c:622
 wait_sb_inodes fs/fs-writeback.c:2440 [inline]
 sync_inodes_sb+0x3b7/0x450 fs/fs-writeback.c:2562
 __sync_filesystem fs/sync.c:34 [inline]
 sync_filesystem+0xe4/0x160 fs/sync.c:67
 generic_shutdown_super+0x3c/0x1f0 fs/super.c:448
 kill_block_super+0x4a/0x90 fs/super.c:1446
 deactivate_locked_super+0x6a/0xb0 fs/super.c:335
 deactivate_super+0x85/0x90 fs/super.c:366
 cleanup_mnt+0x277/0x2e0 fs/namespace.c:1118
 __cleanup_mnt+0x15/0x20 fs/namespace.c:1125
 task_work_run+0x8e/0x110 kernel/task_work.c:141
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:165 [inline]
 exit_to_user_mode_prepare+0x1a4/0x200 kernel/entry/common.c:192
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:267
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 8723 Comm: syz-executor.1 Not tainted 5.9.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (507):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Maintainers
ci2-upstream-kcsan-gce	2020/10/21 02:15	upstream	c4d6fe73	ff4a3345	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/20 12:25	upstream	270315b8	ff4a3345	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/19 22:25	upstream	bbe85027	ff4a3345	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/19 08:54	upstream	7cf726a5	ff4a3345	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/18 17:50	upstream	9453b2d4	fea47c01	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/18 02:01	upstream	9d9af100	fea47c01	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/16 22:56	upstream	54a4c789	6e262c73	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/16 09:27	upstream	9ff9b0d3	6e262c73	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/15 20:10	upstream	726eb70e	6e262c73	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/15 17:49	upstream	726eb70e	63869021	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/15 08:14	upstream	3e4fb434	63869021	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/14 23:56	upstream	3e4fb434	fc7735a2	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/14 10:36	upstream	b5fc7a89	fc7735a2	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/13 21:12	upstream	6ad4bf6e	fc7735a2	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/12 18:56	upstream	1e6d1d96	d32b0bbf	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/12 15:39	upstream	bbf5c979	d32b0bbf	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/11 18:49	upstream	3dd0130f	4a77ae0b	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/10 23:51	upstream	da690031	4a77ae0b	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/10 21:16	upstream	6f2f486d	4a77ae0b	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/10 10:01	upstream	6f2f486d	b74c49a6	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/09 21:49	upstream	8a5f78d9	93817d89	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/09 08:57	upstream	583090b1	fa79ed2a	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/08 19:43	upstream	3d006ee4	92390980	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/08 10:39	upstream	c85fb28b	92390980	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/06 19:54	upstream	c85fb28b	1880b4a9	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/05 20:59	upstream	7575fdda	1880b4a9	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/05 13:17	upstream	549738f1	1880b4a9	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/03 20:42	upstream	22fbc037	1a3f9408	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/03 15:48	upstream	d3d45f82	1a3f9408	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/03 03:36	upstream	d3d45f82	2653fa43	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/03 03:29	upstream	d3d45f82	062c9832	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/02 13:06	upstream	472e5b05	062c9832	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/01 20:11	upstream	fcadab74	4103fce0	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/10/01 08:25	upstream	60e72093	4103fce0	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/30 21:55	upstream	60e72093	a9767fb2	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/30 18:35	upstream	02de58b2	a9767fb2	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/30 05:23	upstream	02de58b2	5abc3f1a	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/29 14:19	upstream	fb0155a0	5abc3f1a	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/28 23:00	upstream	fb0155a0	1b88c6d5	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/28 07:53	upstream	a1b8638b	6bfdbe89	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/28 01:56	upstream	a1b8638b	5dd8aee8	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/27 12:39	upstream	a1bffa48	5dd8aee8	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/26 23:11	upstream	eeddbe68	5dd8aee8	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/09/26 18:51	upstream	eeddbe68	2d5ea0cb	.config	log	report	info	akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/07/01 10:44	upstream	7c30b859	090d8f7b	.config	log	report		akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/06/27 10:51	upstream	1590a2e1	032b4239	.config	log	report		akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org
ci2-upstream-kcsan-gce	2020/06/18 14:11	upstream	1b504402	3ea11d3f	.config	log	report		akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org