syzbot

 sign-in | mailing list | source | docs
🐞 Open [717]
🐞 Fixed [181]
🐞 Invalid [640]
Kernel Health Bugs/Month Bug Lifetimes Fuzzing Crashes
💬 Send us feedback

INFO: task hung in blkdev_put (3)

Status: upstream: reported C repro on 2020/08/30 21:52
Reported-by: syzbot+1f4ecbe714743132417a@syzkaller.appspotmail.com
First crash: 1500d, last: 722d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Similar bugs (14)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in blkdev_put (3) fs 1 1626d 1626d 0/28 auto-closed as invalid on 2020/06/25 13:28
android-49 INFO: task hung in blkdev_put (2) 3 1789d 1809d 0/3 auto-closed as invalid on 2020/03/14 12:22
linux-4.19 INFO: task hung in blkdev_put C error 31 773d 1538d 0/1 upstream: reported C repro on 2020/07/23 21:33
upstream INFO: task hung in blkdev_put udf 320 2068d 2494d 0/28 closed as dup on 2018/11/11 08:29
linux-4.14 INFO: task hung in blkdev_put 2 1852d 2001d 0/1 auto-closed as invalid on 2020/01/12 01:56
linux-5.15 INFO: task hung in blkdev_put origin:upstream C error 5 102d 474d 0/3 upstream: reported C repro on 2023/06/23 01:15
upstream INFO: task hung in blkdev_put (4) block C done error 486 210d 1466d 0/28 upstream: reported C repro on 2020/10/03 13:09
android-49 INFO: task hung in blkdev_put 220 1988d 2005d 0/3 auto-closed as invalid on 2019/10/25 08:47
linux-4.14 INFO: task hung in blkdev_put (2) 2 1655d 1693d 0/1 auto-closed as invalid on 2020/07/26 14:38
android-414 INFO: task hung in blkdev_put 119 1774d 2006d 0/1 auto-closed as invalid on 2020/03/30 04:06
android-44 INFO: task hung in blkdev_put 26 2074d 2005d 0/2 auto-closed as invalid on 2019/08/03 02:42
android-44 INFO: task hung in blkdev_put (2) 3 1785d 1862d 0/2 auto-closed as invalid on 2020/03/18 19:27
linux-6.1 INFO: task hung in blkdev_put origin:upstream C 199 16h01m 533d 0/3 upstream: reported C repro on 2023/04/25 09:01
upstream INFO: task hung in blkdev_put (2) fs 2 1781d 1827d 0/28 auto-closed as invalid on 2020/02/22 04:07
▶ ▼ Fix bisection attempts (10)
Created Duration User Patch Repo Result
2021/11/10 20:14 9m bisect fix linux-4.14.y error job log
2021/10/11 19:43 30m bisect fix linux-4.14.y OK (0) job log log
2021/09/11 15:53 30m bisect fix linux-4.14.y OK (0) job log log
2021/08/12 12:29 30m bisect fix linux-4.14.y OK (0) job log log
2021/07/13 12:04 25m bisect fix linux-4.14.y OK (0) job log log
2021/06/13 11:34 29m bisect fix linux-4.14.y OK (0) job log log
2021/05/01 13:10 28m bisect fix linux-4.14.y OK (0) job log log
2021/03/03 18:18 30m bisect fix linux-4.14.y OK (0) job log log
2020/12/01 16:49 40m bisect fix linux-4.14.y OK (0) job log log
2020/10/04 09:11 32m bisect fix linux-4.14.y OK (0) job log log

Sample crash report:
block nbd0: shutting down sockets
INFO: task syz-executor340:7970 blocked for more than 140 seconds.
      Not tainted 4.14.288-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor340 D28464  7970   7969 0x80000006
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:3489
 __mutex_lock_common kernel/locking/mutex.c:833 [inline]
 __mutex_lock+0x669/0x1310 kernel/locking/mutex.c:893
 blkdev_put+0x27/0x4c0 fs/block_dev.c:1826
 blkdev_close+0x86/0xb0 fs/block_dev.c:1875
 __fput+0x25f/0x7a0 fs/file_table.c:210
 task_work_run+0x11f/0x190 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xa44/0x2850 kernel/exit.c:868
 do_group_exit+0x100/0x2e0 kernel/exit.c:965
 get_signal+0x38d/0x1ca0 kernel/signal.c:2412
 do_signal+0x7c/0x1550 arch/x86/kernel/signal.c:792
 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160
 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:270 [inline]
 do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7f542c2cd3e9
RSP: 002b:00007ffefaa122d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 0000000000000000 RCX: 00007f542c2cd3e9
RDX: 0000000000000000 RSI: 000000000000ab03 RDI: 0000000000000004
RBP: 0000000000000000 R08: 00007ffefaa12478 R09: 00007ffefaa12478
R10: 00007ffefaa12478 R11: 0000000000000246 R12: 00007f542c28c700
R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000
INFO: task systemd-udevd:7973 blocked for more than 140 seconds.
      Not tainted 4.14.288-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
systemd-udevd   D27464  7973   4626 0x00000304
Call Trace:
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x88b/0x1de0 kernel/sched/core.c:3387
 schedule+0x8d/0x1b0 kernel/sched/core.c:3431
 io_schedule+0xb5/0x120 kernel/sched/core.c:5035
 wait_on_page_bit_common mm/filemap.c:1025 [inline]
 wait_on_page_bit+0x241/0x320 mm/filemap.c:1058
 wait_on_page_locked include/linux/pagemap.h:527 [inline]
 wait_on_page_read mm/filemap.c:2680 [inline]
 do_read_cache_page+0x55f/0xc10 mm/filemap.c:2719
 read_mapping_page include/linux/pagemap.h:398 [inline]
 read_dev_sector+0xbd/0x3c0 block/partition-generic.c:659
 read_part_sector block/partitions/check.h:38 [inline]
 adfspart_check_ICS+0xf6/0xc00 block/partitions/acorn.c:366
 check_partition+0x330/0x610 block/partitions/check.c:167
 rescan_partitions+0x192/0x800 block/partition-generic.c:523
 __blkdev_get+0xd7f/0x1090 fs/block_dev.c:1541
 blkdev_get+0x88/0x890 fs/block_dev.c:1611
 blkdev_open+0x1cc/0x250 fs/block_dev.c:1772
 do_dentry_open+0x44b/0xec0 fs/open.c:777
 vfs_open+0x105/0x220 fs/open.c:888
 do_last fs/namei.c:3428 [inline]
 path_openat+0x628/0x2970 fs/namei.c:3569
 do_filp_open+0x179/0x3c0 fs/namei.c:3603
 do_sys_open+0x296/0x410 fs/open.c:1081
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x46/0xbb
RIP: 0033:0x7fe307706840
RSP: 002b:00007ffdd87bb578 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 000055bf57b20880 RCX: 00007fe307706840
RDX: 000055bf56e52fe3 RSI: 00000000000a0800 RDI: 000055bf57b22210
RBP: 00007ffdd87bb6f0 R08: 000055bf56e52670 R09: 0000000000000010
R10: 000055bf56e52d0c R11: 0000000000000246 R12: 00007ffdd87bb640
R13: 000055bf57b23070 R14: 0000000000000003 R15: 000000000000000e

Showing all locks held in the system:
1 lock held by khungtaskd/1534:
 #0:  (tasklist_lock){.+.+}, at: [<ffffffff8701dc79>] debug_show_all_locks+0x7c/0x21a kernel/locking/lockdep.c:4548
1 lock held by syz-executor340/7970:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff81940a47>] blkdev_put+0x27/0x4c0 fs/block_dev.c:1826
1 lock held by systemd-udevd/7973:
 #0:  (&bdev->bd_mutex){+.+.}, at: [<ffffffff81941f81>] __blkdev_get+0x191/0x1090 fs/block_dev.c:1455

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

NMI backtrace for cpu 0
CPU: 0 PID: 1534 Comm: khungtaskd Not tainted 4.14.288-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/29/2022
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x1b2/0x281 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x13a/0x180 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:140 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:195 [inline]
 watchdog+0x5b9/0xb40 kernel/hung_task.c:274
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff8723e38e

Crashes (16):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/07/16 23:49 linux-4.14.y 424a46ea058e 95cb00d1 .config console log report syz C ci2-linux-4-14 INFO: task hung in blkdev_put
2022/07/03 14:27 linux-4.14.y ed2e96e11936 1434eec0 .config console log report syz C ci2-linux-4-14 INFO: task hung in blkdev_put
2021/05/14 11:34 linux-4.14.y 7d7d1c0ab3eb 8bdd5343 .config console log report syz C ci2-linux-4-14 INFO: task hung in blkdev_put
2020/12/26 18:31 linux-4.14.y 3f2ecb86cb90 821e0b09 .config console log report syz C ci2-linux-4-14
2020/11/01 16:49 linux-4.14.y 2b7915014161 8bc4594f .config console log report syz C ci2-linux-4-14
2020/08/30 21:51 linux-4.14.y d7e78d08fa77 d5a3ae1f .config console log report syz C ci2-linux-4-14
2022/10/17 18:36 linux-4.14.y 9d5c0b3a8e1a 94744d21 .config console log report info [disk image] [vmlinux] ci2-linux-4-14 INFO: task hung in blkdev_put
2022/06/25 21:37 linux-4.14.y f051383ef03b a371c43c .config console log report info ci2-linux-4-14 INFO: task hung in blkdev_put
2021/12/15 11:07 linux-4.14.y 9dfbac0e6b86 f752fb53 .config console log report info ci2-linux-4-14 INFO: task hung in blkdev_put
2021/04/01 13:10 linux-4.14.y bd634aa64163 6a81331a .config console log report info ci2-linux-4-14 INFO: task hung in blkdev_put
2021/03/30 23:07 linux-4.14.y bd634aa64163 6a81331a .config console log report info ci2-linux-4-14 INFO: task hung in blkdev_put
2021/02/01 18:18 linux-4.14.y 2c8a3fceddf0 e6b95f32 .config console log report info ci2-linux-4-14 INFO: task hung in blkdev_put
2021/01/16 00:23 linux-4.14.y f79dc86058bc 65a7a854 .config console log report info ci2-linux-4-14
2021/01/09 01:17 linux-4.14.y 1752938529c6 c104d4a3 .config console log report info ci2-linux-4-14
2020/10/19 04:30 linux-4.14.y cbfa1702aaf6 fea47c01 .config console log report info ci2-linux-4-14
2020/09/04 05:46 linux-4.14.y 2f166cdcf8a9 abf9ba4f .config console log report ci2-linux-4-14
* Struck through repros no longer work on HEAD.