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INFO: task hung in blkdev_put

Status: upstream: reported C repro on 2020/07/23 21:33
Reported-by: syzbot+cded3bd87b0c7c49c717@syzkaller.appspotmail.com
First crash: 1926d, last: 1162d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (15)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in blkdev_put (3) fs 1 1 2015d 2015d 0/29 auto-closed as invalid on 2020/06/25 13:28
android-49 INFO: task hung in blkdev_put (2) 1 3 2178d 2197d 0/3 auto-closed as invalid on 2020/03/14 12:22
upstream INFO: task hung in blkdev_put udf 1 320 2456d 2883d 0/29 closed as dup on 2018/11/11 08:29
linux-6.6 INFO: task hung in blkdev_put origin:upstream missing-backport 1 C 3 20d 101d 0/2 upstream: reported C repro on 2025/07/23 11:17
linux-4.14 INFO: task hung in blkdev_put 1 2 2240d 2390d 0/1 auto-closed as invalid on 2020/01/12 01:56
linux-5.15 INFO: task hung in blkdev_put origin:upstream 1 C error 5 491d 862d 0/3 upstream: reported C repro on 2023/06/23 01:15
linux-4.14 INFO: task hung in blkdev_put (3) 1 C error 16 1111d 1888d 0/1 upstream: reported C repro on 2020/08/30 21:52
upstream INFO: task hung in blkdev_put (4) block 1 C done error 486 599d 1855d 0/29 upstream: reported C repro on 2020/10/03 13:09
android-49 INFO: task hung in blkdev_put 1 220 2376d 2393d 0/3 auto-closed as invalid on 2019/10/25 08:47
linux-4.14 INFO: task hung in blkdev_put (2) 1 2 2044d 2082d 0/1 auto-closed as invalid on 2020/07/26 14:38
android-414 INFO: task hung in blkdev_put 1 119 2162d 2394d 0/1 auto-closed as invalid on 2020/03/30 04:06
android-44 INFO: task hung in blkdev_put 1 26 2462d 2393d 0/2 auto-closed as invalid on 2019/08/03 02:42
android-44 INFO: task hung in blkdev_put (2) 1 3 2174d 2251d 0/2 auto-closed as invalid on 2020/03/18 19:27
linux-6.1 INFO: task hung in blkdev_put origin:upstream 1 C 230 20d 921d 0/3 upstream: reported C repro on 2023/04/25 09:01
upstream INFO: task hung in blkdev_put (2) fs 1 2 2169d 2215d 0/29 auto-closed as invalid on 2020/02/22 04:07
▶ ▼ Fix bisection attempts (6)
Created Duration User Patch Repo Result
2021/11/24 01:03 14m bisect fix linux-4.19.y error job log
2021/09/06 02:38 35m bisect fix linux-4.19.y OK (0) job log log
2021/07/17 22:56 29m bisect fix linux-4.19.y OK (0) job log log
2021/06/17 22:29 27m bisect fix linux-4.19.y OK (0) job log log
2021/03/26 06:48 26m bisect fix linux-4.19.y OK (0) job log log
2020/12/21 22:04 32m bisect fix linux-4.19.y OK (0) job log log

Sample crash report:
block nbd0: shutting down sockets
INFO: task syz-executor494:8106 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor494 D28248  8106   8105 0x80000006
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3619
 __mutex_lock_common kernel/locking/mutex.c:1016 [inline]
 __mutex_lock+0x5f0/0x1190 kernel/locking/mutex.c:1078
 blkdev_put+0x30/0x520 fs/block_dev.c:1839
 blkdev_close+0x86/0xb0 fs/block_dev.c:1888
 __fput+0x2ce/0x890 fs/file_table.c:278
 task_work_run+0x148/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xbf3/0x2be0 kernel/exit.c:870
 do_group_exit+0x125/0x310 kernel/exit.c:967
 get_signal+0x3f2/0x1f70 kernel/signal.c:2589
 do_signal+0x8f/0x1670 arch/x86/kernel/signal.c:799
 exit_to_usermode_loop+0x204/0x2a0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x538/0x620 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f43022cf3e9
Code: Bad RIP value.
RSP: 002b:00007ffddc013d48 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f43022cf3e9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007ffddc013ee8 R09: 00007ffddc013ee8
R10: 00007ffddc013ee8 R11: 0000000000000246 R12: 00007f430228e700
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
INFO: task systemd-udevd:8110 blocked for more than 140 seconds.
      Not tainted 4.19.211-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
systemd-udevd   D26624  8110   4695 0x00000104
Call Trace:
 context_switch kernel/sched/core.c:2828 [inline]
 __schedule+0x887/0x2040 kernel/sched/core.c:3517
 schedule+0x8d/0x1b0 kernel/sched/core.c:3561
 io_schedule+0xb5/0x120 kernel/sched/core.c:5181
 wait_on_page_bit_common mm/filemap.c:1123 [inline]
 wait_on_page_bit+0x2c5/0x3f0 mm/filemap.c:1156
 wait_on_page_locked include/linux/pagemap.h:531 [inline]
 wait_on_page_read mm/filemap.c:2795 [inline]
 do_read_cache_page+0x8ed/0x1170 mm/filemap.c:2834
 read_mapping_page include/linux/pagemap.h:402 [inline]
 read_dev_sector+0xbf/0x500 block/partition-generic.c:671
 read_part_sector block/partitions/check.h:38 [inline]
 adfspart_check_ICS+0x114/0xe70 block/partitions/acorn.c:366
 check_partition+0x390/0x690 block/partitions/check.c:167
 rescan_partitions+0x1b5/0x970 block/partition-generic.c:535
 bdev_disk_changed+0x179/0x1b0 fs/block_dev.c:1435
 __blkdev_get+0x1282/0x1480 fs/block_dev.c:1561
 blkdev_get+0xb0/0x940 fs/block_dev.c:1627
 blkdev_open+0x202/0x290 fs/block_dev.c:1788
 do_dentry_open+0x4aa/0x1160 fs/open.c:796
 do_last fs/namei.c:3421 [inline]
 path_openat+0x793/0x2df0 fs/namei.c:3537
 do_filp_open+0x18c/0x3f0 fs/namei.c:3567
 do_sys_open+0x3b3/0x520 fs/open.c:1085
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f53cd82c840
Code: Bad RIP value.
RSP: 002b:00007ffd38c089f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 000055a2cceaa6e0 RCX: 00007f53cd82c840
RDX: 000055a2cb862fe3 RSI: 00000000000a0800 RDI: 000055a2cceaf1b0
RBP: 00007ffd38c08b70 R08: 000055a2cb862670 R09: 0000000000000010
R10: 000055a2cb862d0c R11: 0000000000000246 R12: 00007ffd38c08ac0
R13: 000055a2ccead880 R14: 0000000000000003 R15: 000000000000000e

Showing all locks held in the system:
1 lock held by khungtaskd/1570:
 #0: 000000008b9a76dd (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x265 kernel/locking/lockdep.c:4441
1 lock held by in:imklog/7804:
 #0: 0000000072a43e60 (&f->f_pos_lock){+.+.}, at: __fdget_pos+0x26f/0x310 fs/file.c:767
1 lock held by syz-executor494/8106:
 #0: 0000000026cdae3f (&bdev->bd_mutex){+.+.}, at: blkdev_put+0x30/0x520 fs/block_dev.c:1839
1 lock held by systemd-udevd/8110:
 #0: 0000000026cdae3f (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x1d0/0x1480 fs/block_dev.c:1478

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1570 Comm: khungtaskd Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x63/0xa2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1a6/0x1f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:203 [inline]
 watchdog+0x991/0xe60 kernel/hung_task.c:287
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4684 Comm: systemd-journal Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
RIP: 0010:unwind_next_frame+0x425/0x1400 arch/x86/kernel/unwind_orc.c:427
Code: f9 4c 89 c7 e8 3c f2 ff ff 48 85 c0 49 89 c7 74 6a 4d 8d 47 04 48 b8 00 00 00 00 00 fc ff df 4c 89 c2 48 c1 ea 03 0f b6 04 02 <4c> 89 c2 83 e2 07 38 d0 7f 08 84 c0 0f 85 23 0c 00 00 41 0f b6 47
RSP: 0018:ffff8880a176f9a8 EFLAGS: 00000a02
RAX: 0000000000000000 RBX: 1ffff110142edf3e RCX: ffffffff81a6b6cd
RDX: 1ffffffff173614c RSI: ffffffff8b9b0a34 RDI: ffffffff8b39c92c
RBP: 0000000000000001 R08: ffffffff8b9b0a62 R09: ffffffff8b9b0a34
R10: ffff8880a176fb37 R11: 0000000000074071 R12: ffff8880a176fb20
R13: ffff8880a176fb0d R14: ffff8880a176fad8 R15: ffffffff8b9b0a5e
FS:  00007f11697668c0(0000) GS:ffff8880ba100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1166b43000 CR3: 00000000a17cf000 CR4: 00000000003406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __save_stack_trace+0x9f/0x190 arch/x86/kernel/stacktrace.c:44
 save_stack mm/kasan/kasan.c:448 [inline]
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xeb/0x160 mm/kasan/kasan.c:553
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc mm/slab.c:3397 [inline]
 kmem_cache_alloc+0x110/0x370 mm/slab.c:3557
 getname_flags+0xce/0x590 fs/namei.c:140
 user_path_at_empty+0x2a/0x50 fs/namei.c:2609
 user_path_at include/linux/namei.h:57 [inline]
 do_faccessat+0x248/0x7a0 fs/open.c:397
 do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f1168a219c7
Code: 83 c4 08 48 3d 01 f0 ff ff 73 01 c3 48 8b 0d c8 d4 2b 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 b8 15 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d a1 d4 2b 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe8bd70d88 EFLAGS: 00000246 ORIG_RAX: 0000000000000015
RAX: ffffffffffffffda RBX: 00007ffe8bd73ca0 RCX: 00007f1168a219c7
RDX: 00007f1169492a00 RSI: 0000000000000000 RDI: 000056455f2599a3
RBP: 00007ffe8bd70dc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000069 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007ffe8bd73ca0 R15: 00007ffe8bd712b0

Crashes (31):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/07/17 02:27 linux-4.19.y 3f8a27f9e27b 95cb00d1 .config console log report syz C ci2-linux-4-19 INFO: task hung in blkdev_put
2022/07/03 12:02 linux-4.19.y 3f8a27f9e27b 1434eec0 .config console log report syz C ci2-linux-4-19 INFO: task hung in blkdev_put
2021/04/06 16:21 linux-4.19.y 2034d6f0838e 6a81331a .config console log report syz C ci2-linux-4-19 INFO: task hung in blkdev_put
2021/02/08 17:18 linux-4.19.y 811218eceeaa 2ce644fc .config console log report syz C ci2-linux-4-19 INFO: task hung in blkdev_put
2021/01/09 20:43 linux-4.19.y 610bdbf6a174 a6c52263 .config console log report syz C ci2-linux-4-19
2020/11/21 22:04 linux-4.19.y 2c746135a12e c7ec2d19 .config console log report syz C ci2-linux-4-19
2022/08/27 12:28 linux-4.19.y 3f8a27f9e27b 07177916 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/07/09 14:43 linux-4.19.y 3f8a27f9e27b b5765a15 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/07/03 08:52 linux-4.19.y 3f8a27f9e27b 1434eec0 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/05/11 07:52 linux-4.19.y 3f8a27f9e27b 8d7b3b67 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/03/11 03:34 linux-4.19.y 3f8a27f9e27b 9e8eaa75 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/02/28 05:12 linux-4.19.y 3f8a27f9e27b 45a13a73 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/02/26 02:10 linux-4.19.y 3f8a27f9e27b 45a13a73 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/02/25 01:40 linux-4.19.y 3f8a27f9e27b b28851a4 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/01/01 19:02 linux-4.19.y 3f8a27f9e27b e1768e9c .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2022/01/01 18:41 linux-4.19.y 3f8a27f9e27b e1768e9c .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/10/25 00:50 linux-4.19.y 3f8a27f9e27b 4f0000ee .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/10/06 06:01 linux-4.19.y c2276d585654 0a63fd36 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/09/27 11:23 linux-4.19.y c2276d585654 78494d16 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/09/10 17:25 linux-4.19.y b172b44fcb17 5ae8508a .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/08/07 02:38 linux-4.19.y 6ca2f514c578 6972b106 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/05/18 22:28 linux-4.19.y 3c8c23092588 a343ba6b .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/05/10 09:06 linux-4.19.y 3c8c23092588 bc5434be .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/05/05 19:55 linux-4.19.y 97a8651cadce 06c27ff5 .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/02/24 06:17 linux-4.19.y 2d19be4653f5 fcc6d71b .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/02/09 22:57 linux-4.19.y 811218eceeaa 2bd9619f .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/02/09 09:35 linux-4.19.y 811218eceeaa 2bd9619f .config console log report info ci2-linux-4-19 INFO: task hung in blkdev_put
2021/01/11 12:53 linux-4.19.y 610bdbf6a174 2c1f2513 .config console log report info ci2-linux-4-19
2020/12/26 06:59 linux-4.19.y 13d2ce42de8c 821e0b09 .config console log report info ci2-linux-4-19
2020/10/14 08:27 linux-4.19.y a1b977b49b66 fc7735a2 .config console log report info ci2-linux-4-19
2020/07/23 21:32 linux-4.19.y 20b3a3dfdf6c 70c104a1 .config console log report ci2-linux-4-19
* Struck through repros no longer work on HEAD.