KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass

KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
Status: moderation: reported on 2020/12/07 11:25
Reported-by: syzbot+cbd503fe55400f0ef6f1@syzkaller.appspotmail.com
First crash: 393d, last: 1d11h

Sample crash report:

==================================================================
BUG: KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert

write to 0xffff888100b4b410 of 8 bytes by task 858 on cpu 1:
 __list_add include/linux/list.h:70 [inline]
 list_add include/linux/list.h:86 [inline]
 blk_mq_request_bypass_insert+0x6a/0x150 block/blk-mq.c:1879
 blk_mq_sched_insert_request+0xfc/0x250 block/blk-mq-sched.c:462
 blk_mq_requeue_work+0x3cb/0x440 block/blk-mq.c:795
 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276
 worker_thread+0x636/0xae0 kernel/workqueue.c:2422
 kthread+0x262/0x280 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

read to 0xffff888100b4b410 of 8 bytes by task 18812 on cpu 0:
 list_empty_careful include/linux/list.h:319 [inline]
 __blk_mq_do_dispatch_sched block/blk-mq-sched.c:140 [inline]
 blk_mq_do_dispatch_sched+0x167/0x640 block/blk-mq-sched.c:214
 __blk_mq_sched_dispatch_requests+0x1eb/0x290 block/blk-mq-sched.c:329
 blk_mq_sched_dispatch_requests+0x9f/0x110 block/blk-mq-sched.c:360
 __blk_mq_run_hw_queue+0xbc/0x140 block/blk-mq.c:1500
 __blk_mq_delay_run_hw_queue+0x163/0x2f0 block/blk-mq.c:1577
 blk_mq_run_hw_queue+0x22c/0x250 block/blk-mq.c:1630
 blk_mq_sched_insert_requests+0x12b/0x1f0 block/blk-mq-sched.c:513
 blk_mq_flush_plug_list+0x2f2/0x3c0 block/blk-mq.c:1955
 blk_flush_plug_list+0x235/0x260 block/blk-core.c:1731
 blk_finish_plug+0x44/0x60 block/blk-core.c:1748
 ext4_writepages+0x18a1/0x1d10 fs/ext4/inode.c:2851
 do_writepages+0x7b/0x150 mm/page-writeback.c:2355
 __filemap_fdatawrite_range mm/filemap.c:413 [inline]
 file_write_and_wait_range+0x180/0x210 mm/filemap.c:792
 ext4_sync_file+0x105/0x670 fs/ext4/fsync.c:151
 vfs_fsync_range+0x107/0x120 fs/sync.c:200
 generic_write_sync include/linux/fs.h:2987 [inline]
 ext4_buffered_write_iter+0x39c/0x3f0 fs/ext4/file.c:277
 ext4_file_write_iter+0x2e7/0x11d0 fs/ext4/file.c:519
 call_write_iter include/linux/fs.h:2114 [inline]
 do_iter_readv_writev+0x2cb/0x360 fs/read_write.c:740
 do_iter_write+0x112/0x4c0 fs/read_write.c:866
 vfs_iter_write+0x4c/0x70 fs/read_write.c:907
 iter_file_splice_write+0x40a/0x750 fs/splice.c:689
 do_splice_from fs/splice.c:767 [inline]
 direct_splice_actor+0x80/0xa0 fs/splice.c:936
 splice_direct_to_actor+0x345/0x650 fs/splice.c:891
 do_splice_direct+0xf5/0x170 fs/splice.c:979
 do_sendfile+0x773/0xda0 fs/read_write.c:1260
 __do_sys_sendfile64 fs/read_write.c:1325 [inline]
 __se_sys_sendfile64 fs/read_write.c:1311 [inline]
 __x64_sys_sendfile64+0xf2/0x130 fs/read_write.c:1311
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffff888100b4b408 -> 0xffff88810266e448

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 18812 Comm: syz-executor.1 Tainted: G        W         5.14.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================
syz-executor.1 (18812) used greatest stack depth: 10032 bytes left

Crashes (111):
Manager	Time	Kernel	Commit	Syzkaller	Config	Log	Report	VM info	Title
ci2-upstream-kcsan-gce	2021/07/22 23:13	upstream	3d5895cd3517	241790bb	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/07/18 19:36	upstream	f0eb870a8422	f115ae98	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/07/14 07:26	upstream	40226a3d96ef	484502bd	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/07/08 19:40	upstream	3dbdb38e2869	1b20171a	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/07/01 13:45	upstream	dbe69e433722	658ebc66	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/30 17:49	upstream	007b350a5875	84fd4c77	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/29 13:20	upstream	c54b245d0118	9d2ab5df	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/26 20:32	upstream	625acffd7ae2	9d2ab5df	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/23 01:44	upstream	0c18f29aae7c	aba2b2fb	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/18 18:07	upstream	fd0aa1a4567d	aba2b2fb	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/17 16:56	upstream	70585216fe77	aba2b2fb	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/16 17:03	upstream	6b00bc639f1f	c06f97ad	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/12 21:22	upstream	ad347abe4a98	1ba81399	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/11 23:55	upstream	f21b807c3cf8	1ba81399	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/10 20:50	upstream	f09eacca59d2	1ba81399	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/09 03:41	upstream	4c8684fe555e	5c2fe346	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/06/02 16:56	upstream	231bc5390667	0740de69	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/28 12:24	upstream	97e5bf604b7a	858ea628	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/24 21:09	upstream	c4681547bcce	3c7fef33	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/21 16:36	upstream	79a106fc6585	3c7fef33	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/16 17:48	upstream	63d1cb53e26a	f54a5c09	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/16 03:39	upstream	c12a29ed9094	f54a5c09	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/15 16:58	upstream	25a1298726e9	93f844de	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/15 08:52	upstream	25a1298726e9	8bdd5343	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/13 10:13	upstream	c06a2ba62fc4	ed7d41c5	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/11 21:27	upstream	88b06399c9c7	b3c3bb8e	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/11 10:24	upstream	1140ab592e2e	ca873091	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/08 05:06	upstream	1ad77a05cfae	bc5434be	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/07 08:03	upstream	e48661230cc3	06585184	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/03 22:41	upstream	6f8ee8d36d07	ad61f371	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/05/02 01:16	upstream	10a3efd0fee5	77e2b668	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/29 18:17	upstream	d72cd4ad4174	77e2b668	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/27 07:03	upstream	9f4ad9e425a1	8ee2dea6	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/22 11:31	upstream	16fc44d6387e	33c28d03	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/21 12:01	upstream	1fe5501ba1ab	95777977	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/20 17:46	upstream	7af08140979a	c0ced557	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/19 00:00	upstream	bf05bf16c76b	7e2b734b	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/15 02:59	upstream	7f75285ca572	fcdb12ba	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/14 14:29	upstream	50987beca096	3134b37f	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/10 03:37	upstream	4e04e7513b0f	6a81331a	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/08 20:13	upstream	454859c552da	6a81331a	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/04/03 09:22	upstream	0a84c2e440f7	6a81331a	.config	log	report	info	KCSAN: data-race in blk_mq_do_dispatch_sched / blk_mq_request_bypass_insert
ci2-upstream-kcsan-gce	2021/01/17 11:10	upstream	0da0a8a0a0e1	813be542	.config	log	report	info
ci2-upstream-kcsan-gce	2020/12/06 20:03	upstream	8100a58044f8	c521566d	.config	log	report	info
ci2-upstream-kcsan-gce	2020/06/25 19:17	upstream	908f7d12d3ba	adb7d9e6	.config	log	report