INFO: task syz.5.23:6506 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.23 state:D
stack:26664 pid:6506 ppid:6401 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_timeout+0x9b/0x280 kernel/time/timer.c:2143
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion+0x2bd/0x590 kernel/sched/completion.c:148
__flush_work+0x895/0x9f0 kernel/workqueue.c:3430
__cancel_work_timer+0x3b0/0x520 kernel/workqueue.c:3517
uhid_dev_destroy drivers/hid/uhid.c:585 [inline]
uhid_char_release+0xaf/0x600 drivers/hid/uhid.c:663
__fput+0x234/0x970 fs/file_table.c:384
task_work_run+0x1ce/0x250 kernel/task_work.c:239
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
exit_to_user_mode_prepare+0xf6/0x180 kernel/entry/common.c:210
__syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7ffb7778f749
RSP: 002b:00007fffaa06c798 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 000000000006cf24 RCX: 00007ffb7778f749
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000001 R09: 00000002aa06ca8f
R10: 0000001b2c020000 R11: 0000000000000246 R12: 00007ffb779e5fac
R13: 00007ffb779e5fa0 R14: ffffffffffffffff R15: 0000000000000003
Showing all locks held in the system:
3 locks held by kworker/1:1/28:
1 lock held by khungtaskd/29:
#0:
ffffffff8cd2fee0
(
rcu_read_lock
){....}-{1:2}
, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
1 lock held by klogd/5148:
2 locks held by getty/5544:
#0: ffff88803118a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock
){+.+.}-{3:3}
, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
3 locks held by kworker/1:0/5832:
3 locks held by kworker/0:4/5893:
3 locks held by kworker/0:5/6102:
1 lock held by syz.5.23/6506:
#0: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:292 [inline]
#0: ffffffff8cd358b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x448/0x830 kernel/rcu/tree_exp.h:1004
3 locks held by kworker/0:6/6690:
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 7430 Comm: dhcpcd-run-hook Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:on_stack arch/x86/include/asm/stacktrace.h:56 [inline]
RIP: 0010:stack_access_ok arch/x86/kernel/unwind_orc.c:393 [inline]
RIP: 0010:deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
RIP: 0010:unwind_next_frame+0xeb3/0x2970 arch/x86/kernel/unwind_orc.c:585
Code: 5c 24 70 4c 89 7c 24 38 48 89 6c 24 10 48 8b 04 24 48 8b 58 08 4c 8d 70 10 4d 89 f5 49 c1 ed 03 48 b8 00 00 00 00 00 fc ff df <41> 80 7c 05 00 00 74 08 4c 89 f7 e8 dd 38 a2 00 4c 89 74 24 58 48
RSP: 0018:ffffc9000b72f3b8 EFLAGS: 00000a06
RAX: dffffc0000000000 RBX: ffffc9000b728000 RCX: 0000000000000003
RDX: ffffffff813ab186 RSI: ffffffff8cb9e770 RDI: 0000000000000002
RBP: ffffc9000b72f4d8 R08: ffff888028245a00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: 1ffff920016e5e92
R13: 1ffff920016e5e93 R14: ffffc9000b72f498 R15: ffffffff8ed80022
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc263183c8 CR3: 0000000060e10000 CR4: 00000000003506e0
Call Trace:
arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x280 mm/slub.c:3852
pagetable_pte_dtor include/linux/mm.h:2998 [inline]
___pte_free_tlb+0x2d/0x130 arch/x86/mm/pgtable.c:55
__pte_free_tlb arch/x86/include/asm/pgalloc.h:61 [inline]
free_pte_range mm/memory.c:193 [inline]
free_pmd_range mm/memory.c:211 [inline]
free_pud_range mm/memory.c:245 [inline]
free_p4d_range mm/memory.c:279 [inline]
free_pgd_range+0x628/0xb10 mm/memory.c:359
free_pgtables+0x697/0x770 mm/memory.c:-1
exit_mmap+0x3e8/0xb50 mm/mmap.c:3313