WARNING in __flush_work

Status: fixed on 2019/11/30 01:15
Reported-by: syzbot+4eb909ad0ee2bbcbd6a3@syzkaller.appspotmail.com
Fix commit: ac3b35f11a06 drm/udl: Replace drm_dev_unref with drm_dev_put
First crash: 2642d, last: 2636d
Fix bisection: fixed by (bisect log) :
commit af48f7d79faeaa9f426b400c6ec332fe669553e0
Author: Thomas Zimmermann <tzimmermann@suse.de>
Date: Mon Jul 15 18:05:57 2019 +0000

  drm/udl: Replace drm_dev_unref with drm_dev_put

  
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in __flush_work (4) media usb -1 C 1 2544d 2544d 0/29 closed as invalid on 2019/08/08 13:27
upstream WARNING in __flush_work (3) usb -1 C 1251 2549d 2659d 12/29 fixed on 2019/08/05 13:45
upstream WARNING in __flush_work block -1 C 402 2728d 2734d 11/29 fixed on 2019/03/06 07:43
upstream WARNING in __flush_work (2) dri -1 C 38 2696d 2697d 11/29 fixed on 2019/03/28 12:00

Sample crash report:
audit: type=1400 audit(1556790458.234:36): avc:  denied  { map } for  pid=8168 comm="syz-executor461" path="/root/syz-executor461427238" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
IPVS: ftp: loaded support on port[0] = 21
md: md0 stopped.
WARNING: CPU: 1 PID: 3214 at kernel/workqueue.c:2911 __flush_work+0x740/0x880 kernel/workqueue.c:2911
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 3214 Comm: kworker/1:2 Not tainted 4.19.38 #6
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: md_misc mddev_delayed_delete
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x263/0x51d kernel/panic.c:185
 __warn.cold+0x20/0x54 kernel/panic.c:540
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x204/0x360 arch/x86/kernel/traps.c:296
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:316
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:997
RIP: 0010:__flush_work+0x740/0x880 kernel/workqueue.c:2911
Code: 74 58 e8 63 59 25 00 fb 66 0f 1f 44 00 00 45 31 e4 e9 86 fd ff ff e8 4f 59 25 00 0f 0b 45 31 e4 e9 77 fd ff ff e8 40 59 25 00 <0f> 0b 45 31 e4 e9 68 fd ff ff e8 31 59 25 00 4c 89 ff 45 31 e4 e8
RSP: 0018:ffff88809bc3f990 EFLAGS: 00010293
RAX: ffff88809bc10640 RBX: dffffc0000000000 RCX: ffffffff8146100b
RDX: 0000000000000000 RSI: ffffffff814616b0 RDI: 0000000000000001
RBP: ffff88809bc3faf8 R08: ffff88809bc10640 R09: ffff88809bc10f08
R10: 0000000000000000 R11: 0000000000000000 R12: ffff88809aca8690
R13: ffff88809bc3fad0 R14: 0000000000000001 R15: 0000000000000001
 __cancel_work_timer+0x3bf/0x520 kernel/workqueue.c:3007
 cancel_work_sync+0x18/0x20 kernel/workqueue.c:3043
 blk_sync_queue+0x33/0x1c0 block/blk-core.c:408
 blk_cleanup_queue+0x404/0x720 block/blk-core.c:807
 md_free+0xcb/0x1b0 drivers/md/md.c:5223
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put.cold+0x28f/0x2ec lib/kobject.c:708
 mddev_delayed_delete+0x34/0x40 drivers/md/md.c:5251
 process_one_work+0x98e/0x1760 kernel/workqueue.c:2153
 worker_thread+0x98/0xe40 kernel/workqueue.c:2296
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (135):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/05/02 09:51 linux-4.19.y a03957ab0fd5 1852eb18 .config console log report syz C ci2-linux-4-19
2019/05/08 06:47 linux-4.19.y 1656b1457209 a7383bfa .config console log report ci2-linux-4-19
2019/05/08 04:52 linux-4.19.y 1656b1457209 a7383bfa .config console log report ci2-linux-4-19
2019/05/08 02:08 linux-4.19.y 1656b1457209 a7383bfa .config console log report ci2-linux-4-19
2019/05/07 23:43 linux-4.19.y 1656b1457209 a7383bfa .config console log report ci2-linux-4-19
2019/05/07 22:29 linux-4.19.y 1656b1457209 a7383bfa .config console log report ci2-linux-4-19
2019/05/07 14:41 linux-4.19.y 1656b1457209 04e9d8ce .config console log report ci2-linux-4-19
2019/05/07 13:30 linux-4.19.y 1656b1457209 04e9d8ce .config console log report ci2-linux-4-19
2019/05/07 12:06 linux-4.19.y 1656b1457209 04e9d8ce .config console log report ci2-linux-4-19
2019/05/07 08:21 linux-4.19.y 1656b1457209 04e9d8ce .config console log report ci2-linux-4-19
2019/05/07 03:49 linux-4.19.y 1656b1457209 148296f4 .config console log report ci2-linux-4-19
2019/05/06 21:43 linux-4.19.y 1656b1457209 148296f4 .config console log report ci2-linux-4-19
2019/05/06 16:54 linux-4.19.y 1656b1457209 148296f4 .config console log report ci2-linux-4-19
2019/05/06 04:41 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/06 01:51 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/06 00:14 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/05 20:52 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/05 18:47 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/05 16:04 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/05 14:59 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/05 13:51 linux-4.19.y 1656b1457209 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/04 11:39 linux-4.19.y ad119c970bbe d28f4ce5 .config console log report ci2-linux-4-19
2019/05/04 09:35 linux-4.19.y ad119c970bbe d28f4ce5 .config console log report ci2-linux-4-19
2019/05/04 05:56 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/04 04:14 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/04 02:56 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/04 00:38 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/03 22:43 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/03 20:48 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/03 18:35 linux-4.19.y a03957ab0fd5 d28f4ce5 .config console log report ci2-linux-4-19
2019/05/03 16:45 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 16:40 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 15:28 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 13:19 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 09:58 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 08:26 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 06:47 linux-4.19.y a03957ab0fd5 1bfa09b9 .config console log report ci2-linux-4-19
2019/05/03 05:27 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 05:26 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 03:31 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 02:57 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 02:32 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 01:28 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 01:24 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 01:22 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/03 01:22 linux-4.19.y a03957ab0fd5 e9039493 .config console log report ci2-linux-4-19
2019/05/02 09:31 linux-4.19.y a03957ab0fd5 1852eb18 .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.