INFO: task hung in blk_freeze_queue

Status: upstream: reported C repro on 2023/06/08 14:42
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+d34e535ffb9e7ef2bc78@syzkaller.appspotmail.com
First crash: 1152d, last: 693d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2023/06/08 upstream (ToT) 5f63595ebd82 C [report] INFO: task hung in blkdev_put
2026/06/09 upstream (ToT) 2d3090a8aeb5 C Failed due to an error; will retry later
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in blk_freeze_queue (4) block 1 2 1192d 1195d 0/29 auto-obsoleted due to no activity on 2023/07/28 15:48
upstream INFO: task hung in blk_freeze_queue block 1 syz, C 188 2949d 3100d 8/29 fixed on 2018/07/09 18:05
upstream INFO: task hung in blk_freeze_queue (3) arm 1 syz, C 8 1354d 1433d 22/29 fixed on 2023/02/24 13:50
upstream INFO: task hung in blk_freeze_queue (5) block 1 1 857d 857d 0/29 auto-obsoleted due to no activity on 2024/06/27 12:04
upstream INFO: task hung in blk_freeze_queue (2) block 1 1 2851d 2851d 0/29 auto-closed as invalid on 2019/04/12 00:55
android-6-12 INFO: task hung in blk_freeze_queue 1 1 380d 380d 0/1 auto-obsoleted due to no activity on 2025/10/17 10:06
▶ ▼ Fix bisection attempts (13)
Created Duration User Patch Repo Result
2024/10/15 01:49 0m bisect fix linux-6.1.y error job log
2024/09/10 04:13 2h02m bisect fix linux-6.1.y OK (0) job log log
2024/08/06 14:20 4h03m bisect fix linux-6.1.y OK (0) job log log
2024/06/27 15:30 2h50m bisect fix linux-6.1.y OK (0) job log log
2024/05/19 04:53 2h11m bisect fix linux-6.1.y OK (0) job log log
2024/04/13 15:09 3h36m bisect fix linux-6.1.y OK (0) job log log
2024/03/11 15:29 2h15m bisect fix linux-6.1.y OK (0) job log log
2024/02/03 02:30 2h50m bisect fix linux-6.1.y OK (0) job log log
2023/12/30 14:39 2h18m bisect fix linux-6.1.y OK (0) job log log
2023/11/30 06:43 2h18m bisect fix linux-6.1.y OK (0) job log log
2023/10/29 20:47 2h12m bisect fix linux-6.1.y OK (0) job log log
2023/09/27 09:58 2h09m bisect fix linux-6.1.y OK (0) job log log
2023/07/19 20:22 6h15m bisect fix linux-6.1.y OK (0) job log log

Sample crash report:
INFO: task syz-executor362:5427 blocked for more than 143 seconds.
      Not tainted 6.1.32-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor362 state:D stack:0     pid:5427  ppid:4239   flags:0x00000001
Call trace:
 __switch_to+0x320/0x754 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xee4/0x1c98 kernel/sched/core.c:6554
 schedule+0xc4/0x170 kernel/sched/core.c:6630
 blk_mq_freeze_queue_wait+0xf4/0x174 block/blk-mq.c:180
 blk_freeze_queue+0xc8/0x104 block/blk-mq.c:207
 blk_mq_freeze_queue+0x20/0x30 block/blk-mq.c:216
 nbd_add_socket+0x174/0x770 drivers/block/nbd.c:1127
 __nbd_ioctl drivers/block/nbd.c:1470 [inline]
 nbd_ioctl+0x20c/0xc40 drivers/block/nbd.c:1527
 blkdev_ioctl+0x408/0xb40 block/ioctl.c:615
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581
INFO: task syz-executor362:5429 blocked for more than 143 seconds.
      Not tainted 6.1.32-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor362 state:D stack:0     pid:5429  ppid:4239   flags:0x00000001
Call trace:
 __switch_to+0x320/0x754 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xee4/0x1c98 kernel/sched/core.c:6554
 schedule+0xc4/0x170 kernel/sched/core.c:6630
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6689
 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679
 __mutex_lock kernel/locking/mutex.c:747 [inline]
 mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
 nbd_ioctl+0x128/0xc40 drivers/block/nbd.c:1520
 blkdev_ioctl+0x408/0xb40 block/ioctl.c:615
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581
INFO: task udevd:5428 blocked for more than 143 seconds.
      Not tainted 6.1.32-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:0     pid:5428  ppid:3837   flags:0x00000004
Call trace:
 __switch_to+0x320/0x754 arch/arm64/kernel/process.c:553
 context_switch kernel/sched/core.c:5241 [inline]
 __schedule+0xee4/0x1c98 kernel/sched/core.c:6554
 schedule+0xc4/0x170 kernel/sched/core.c:6630
 io_schedule+0x8c/0x188 kernel/sched/core.c:8774
 folio_wait_bit_common+0x65c/0xb90 mm/filemap.c:1296
 folio_put_wait_locked mm/filemap.c:1465 [inline]
 do_read_cache_folio+0xa8/0x544 mm/filemap.c:3517
 read_cache_folio+0x68/0x84 mm/filemap.c:3567
 read_mapping_folio include/linux/pagemap.h:762 [inline]
 read_part_sector+0xdc/0x2c8 block/partitions/core.c:717
 adfspart_check_ICS+0xd4/0x860 block/partitions/acorn.c:360
 check_partition block/partitions/core.c:146 [inline]
 blk_add_partitions block/partitions/core.c:602 [inline]
 bdev_disk_changed+0x6e4/0x116c block/partitions/core.c:688
 blkdev_get_whole+0x298/0x348 block/bdev.c:685
 blkdev_get_by_dev+0x390/0x8ec block/bdev.c:822
 blkdev_open+0x10c/0x290 block/fops.c:500
 do_dentry_open+0x734/0xfa0 fs/open.c:882
 vfs_open+0x7c/0x90 fs/open.c:1013
 do_open fs/namei.c:3557 [inline]
 path_openat+0x1e14/0x2548 fs/namei.c:3714
 do_filp_open+0x1bc/0x3cc fs/namei.c:3741
 do_sys_openat2+0x128/0x3d8 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1345
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x218 arch/arm64/kernel/syscall.c:206
 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffff800015794e70 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffff800015795670 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffff800015794ca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:305
2 locks held by getty/3975:
 #0: ffff0000d7cb0098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80001ba502f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1210 drivers/tty/n_tty.c:2177
1 lock held by syz-executor362/5427:
 #0: ffff0000ceefa198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x128/0xc40 drivers/block/nbd.c:1520
1 lock held by syz-executor362/5429:
 #0: ffff0000ceefa198 (&nbd->config_lock){+.+.}-{3:3}, at: nbd_ioctl+0x128/0xc40 drivers/block/nbd.c:1520
1 lock held by udevd/5428:
 #0: ffff0000ceef44c8 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x12c/0x8ec block/bdev.c:813

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

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/06/08 14:41 linux-6.1.y 76ba310227d2 058b3a5a .config console log report syz C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 INFO: task hung in blk_freeze_queue
* Struck through repros no longer work on HEAD.