syzbot


INFO: task hung in sync_bdevs

Status: upstream: reported on 2024/05/23 17:12
Reported-by: syzbot+c408e640ee63c67e9381@syzkaller.appspotmail.com
First crash: 24d, last: 24d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in sync_bdevs block 5 406d 609d 0/27 auto-obsoleted due to no activity on 2023/08/05 18:35

Sample crash report:
INFO: task syz-executor.2:4083 blocked for more than 144 seconds.
      Not tainted 5.15.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2  state:D stack:    0 pid: 4083 ppid:  3999 flags:0x0000000d
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518
 __mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
 sync_bdevs+0x150/0x280 block/bdev.c:1050
 ksys_sync+0xdc/0x1cc fs/sync.c:105
 __arm64_sys_sync+0x14/0x24 fs/sync.c:113
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task syz-executor.3:4107 blocked for more than 144 seconds.
      Not tainted 5.15.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:    0 pid: 4107 ppid:  4000 flags:0x0000000d
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6518
 __mutex_lock_common+0xba0/0x2154 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0xa4/0xf8 kernel/locking/mutex.c:743
 blkdev_put+0xe0/0x6b0 block/bdev.c:912
 blkdev_close+0x74/0xb0 block/fops.c:475
 __fput+0x30c/0x7f0 fs/file_table.c:280
 ____fput+0x20/0x30 fs/file_table.c:308
 task_work_run+0x130/0x1e4 kernel/task_work.c:164
 get_signal+0x1450/0x1550 kernel/signal.c:2661
 do_signal arch/arm64/kernel/signal.c:890 [inline]
 do_notify_resume+0x3d0/0x32b8 arch/arm64/kernel/signal.c:943
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline]
 el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
INFO: task udevd:4110 blocked for more than 144 seconds.
      Not tainted 5.15.159-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd           state:D stack:    0 pid: 4110 ppid:  3590 flags:0x0000000c
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 io_schedule+0x8c/0x194 kernel/sched/core.c:8484
 wait_on_page_bit_common+0x6fc/0xc14 mm/filemap.c:1356
 wait_on_page_bit mm/filemap.c:1417 [inline]
 wait_on_page_locked include/linux/pagemap.h:688 [inline]
 wait_on_page_read mm/filemap.c:3437 [inline]
 do_read_cache_page+0x760/0x950 mm/filemap.c:3480
 read_cache_page+0x68/0x84 mm/filemap.c:3574
 read_mapping_page include/linux/pagemap.h:515 [inline]
 read_part_sector+0xe8/0x4d8 block/partitions/core.c:729
 adfspart_check_ICS+0xd4/0x5d0 block/partitions/acorn.c:360
 check_partition block/partitions/core.c:148 [inline]
 blk_add_partitions block/partitions/core.c:614 [inline]
 bdev_disk_changed+0x83c/0x1358 block/partitions/core.c:700
 blkdev_get_whole+0x2a0/0x344 block/bdev.c:682
 blkdev_get_by_dev+0x238/0x89c block/bdev.c:824
 blkdev_open+0x10c/0x274 block/fops.c:463
 do_dentry_open+0x780/0xed8 fs/open.c:826
 vfs_open+0x7c/0x90 fs/open.c:956
 do_open fs/namei.c:3608 [inline]
 path_openat+0x1ea0/0x26cc fs/namei.c:3742
 do_filp_open+0x1a8/0x3b4 fs/namei.c:3769
 do_sys_openat2+0x128/0x3d8 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __arm64_sys_openat+0x1f0/0x240 fs/open.c:1280
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
2 locks held by kworker/1:1/25:
 #0: ffff0000c0020938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800018a87c00 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
1 lock held by khungtaskd/27:
 #0: ffff800014b214a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
3 locks held by kworker/u4:2/148:
 #0: ffff0000c038c138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001a467c00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff800016a3b4d0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf4/0x9bc net/core/net_namespace.c:561
2 locks held by getty/3729:
 #0: ffff0000d3941098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001a35e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
1 lock held by syz-fuzzer/3964:
3 locks held by syz-executor.4/3997:
 #0: ffff0000e4744ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/23 17:11 linux-5.15.y 83655231580b 4c2072ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-arm64 INFO: task hung in sync_bdevs
* Struck through repros no longer work on HEAD.