INFO: task syz-executor:8235 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21816 pid:8235 tgid:8235 ppid:1 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5533 [inline]
__schedule+0x17db/0x58f0 kernel/sched/core.c:7284
__schedule_loop kernel/sched/core.c:7361 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7376
bit_wait+0x11/0xd0 kernel/sched/wait_bit.c:248
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit include/linux/wait_bit.h:78 [inline]
gfs2_glock_wait+0xbd/0x2a0 fs/gfs2/glock.c:1244
gfs2_glock_nq_init fs/gfs2/glock.h:253 [inline]
__gfs2_lookup+0x131/0x2b0 fs/gfs2/inode.c:1000
__lookup_slow+0x1fb/0x2f0 fs/namei.c:1919
lookup_slow+0x53/0x70 fs/namei.c:1936
walk_component fs/namei.c:2282 [inline]
lookup_last fs/namei.c:2789 [inline]
path_lookupat+0x3f5/0x8c0 fs/namei.c:2813
filename_lookup+0x265/0x5d0 fs/namei.c:2842
user_path_at+0x40/0x160 fs/namei.c:3641
ksys_umount fs/namespace.c:2067 [inline]
__do_sys_umount fs/namespace.c:2075 [inline]
__se_sys_umount fs/namespace.c:2073 [inline]
__x64_sys_umount+0xf6/0x170 fs/namespace.c:2073
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa54039f397
RSP: 002b:00007ffcd5bd5318 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 00007fa5404344bb RCX: 00007fa54039f397
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcd5bd53d0
RBP: 00007ffcd5bd53d0 R08: 0000000000000000 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffcd5bd64c0
R13: 00007fa5404344bb R14: 0000000000053341 R15: 00007ffcd5bd8680
Showing all locks held in the system:
locks held by pool_workqueue_/3: 1, on CPU#0:
#0: ffffffff8ed62c68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8ed62c68 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770 kernel/rcu/tree_exp.h:966
locks held by khungtaskd/32: 1, last CPU#1:
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:9/1114: 3, last CPU#1:
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc90005057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90005057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90005057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc90005057c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffff888032712258 (&devlink->lock_key#24){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40 drivers/net/netdevsim/dev.c:834
locks held by kworker/u8:12/3344: 4, last CPU#1:
#0: ffff88801e3ea140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801e3ea140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801e3ea140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88801e3ea140 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc9000f34fc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000f34fc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000f34fc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc9000f34fc40 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffff8880407a20a0 (&ctx->uring_lock){+.+.}-{4:4}, at: class_mutex_constructor include/linux/mutex.h:253 [inline]
#2: ffff8880407a20a0 (&ctx->uring_lock){+.+.}-{4:4}, at: io_req_caches_free+0x19/0x30 io_uring/io_uring.c:2152
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#3: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by getty/5374: 2, on CPU#0:
#0: ffff88803582d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/8235: 1, on CPU#1:
#0: ffff88805559a780 (&type->i_mutex_dir_key#20){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1039 [inline]
#0: ffff88805559a780 (&type->i_mutex_dir_key#20){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1935
locks held by syz-executor/10962: 1, last CPU#1:
#0: ffff888033a18460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
locks held by kworker/u8:11/11097: 3, last CPU#0:
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#0: ffff88801b0a4140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#1: ffffc90003677c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90003677c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90003677c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline]
#1: ffffc90003677c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479
#2: ffff8880793da258 (&devlink->lock_key#22){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40 drivers/net/netdevsim/dev.c:834
locks held by syz-executor/11281: 1, last CPU#0:
#0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:198 [inline]
#0: ffffffff8eeac630 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:305
locks held by udevd/11521: 1, last CPU#0:
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __update_page_owner_free_handle+0x2e/0x4a0 mm/page_owner.c:301
locks held by syz.5.1041/11701: 2, last CPU#0:
#0: ffff888033a18460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump fs/coredump.c:1126 [inline]
#0: ffff888033a18460 (sb_writers#5){.+.+}-{0:0}, at: vfs_coredump+0x3764/0x4520 fs/coredump.c:1195
#1: ffff888033a08340 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock_killable include/linux/mmap_lock.h:609 [inline]
#1: ffff888033a08340 (&mm->mmap_lock){++++}-{4:4}, at: dump_user_range+0x1c5/0x12c0 fs/coredump.c:1349
locks held by syz.0.1085/11887: 2, last CPU#0:
#0: ffff88807d67ccc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88807d67ccc0 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: class_rcu_constructor include/linux/rcupdate.h:1216 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: unwind_next_frame+0x8f/0x2550 arch/x86/kernel/unwind_orc.c:495
locks held by syz.0.1085/11889: 2, last CPU#1:
#0: ffff888034fb8460 (sb_writers#5){.+.+}-{0:0}, at: do_coredump fs/coredump.c:1126 [inline]
#0: ffff888034fb8460 (sb_writers#5){.+.+}-{0:0}, at: vfs_coredump+0x3764/0x4520 fs/coredump.c:1195
#1: ffff88804cd00e98 (&sb->s_type->i_mutex_key#15){++++}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#1: ffff88804cd00e98 (&sb->s_type->i_mutex_key#15){++++}-{4:4}, at: shmem_file_write_iter+0x7f/0x120 mm/shmem.c:3433
locks held by sed/11891: 1, last CPU#1:
#0: ffff8880578ba088 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
locks held by syz.6.1083/11895: 2, last CPU#0:
#0: ffff88807f464080 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:600 [inline]
#0: ffff88807f464080 (&mm->mmap_lock){++++}-{4:4}, at: exit_mmap+0x1a4/0x9f0 mm/mmap.c:1299
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: __pte_offset_map+0x29/0x240 mm/pgtable-generic.c:290
locks held by syz-executor/11899: 2, last CPU#0:
#0: ffff88807d41c448 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: count_memcg_events_mm include/linux/memcontrol.h:990 [inline]
#1: ffffffff8ed5c8a0 (rcu_read_lock){....}-{1:3}, at: count_memcg_event_mm+0x21/0x260 include/linux/memcontrol.h:1000
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 32 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16 Comm: pr/ttyS0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:409
Code: e8 ee 5a 54 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 ef 6f c4 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 f5 8e 9c fb cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900001578b8 EFLAGS: 00000002
RAX: 1ffffffff35a8a00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff8573b190 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9ad45320 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888124dc6000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555ce8ea38 CR3: 000000007cde9000 CR4: 0000000000350ef0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x184/0x2f0 drivers/tty/serial/8250/8250_port.c:2013
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline]
__serial8250_console_fifo_write+0xcd/0x3e0 drivers/tty/serial/8250/8250_port.c:3345
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline]
serial8250_console_write+0xaa1/0x1200 drivers/tty/serial/8250/8250_port.c:3493
nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
nbcon_emit_one kernel/printk/nbcon.c:1157 [inline]
nbcon_kthread_func+0x679/0x880 kernel/printk/nbcon.c:1271
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245