INFO: task syz.1.879:7912 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.879 state:D stack:23760 pid: 7912 ppid: 4185 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5049 [inline]
__schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
schedule+0x11b/0x1e0 kernel/sched/core.c:6478
perf_pending_task_sync+0x13c/0x1c0 kernel/events/core.c:5127
_free_event+0x34/0xe60 kernel/events/core.c:5133
put_event kernel/events/core.c:5258 [inline]
perf_event_release_kernel+0x83e/0x8d0 kernel/events/core.c:5383
perf_release+0x37/0x40 kernel/events/core.c:5393
__fput+0x234/0x930 fs/file_table.c:311
task_work_run+0x125/0x1a0 kernel/task_work.c:188
get_signal+0x1222/0x12c0 kernel/signal.c:2672
arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f76872f0819
RSP: 002b:00007f7685549fd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007f7687569fa0 RCX: 00007f76872f0819
RDX: 0000200000000200 RSI: 00002000000001d0 RDI: 0000000040800000
RBP: 00007f7687386c91 R08: 0000200000000280 R09: 0000200000000280
R10: 0000200000000240 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f768756a038 R14: 00007f7687569fa0 R15: 00007ffcf22da2b8
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8c31eb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by udevd/3560:
2 locks held by getty/3948:
#0: ffff88814c9dc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025e62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
2 locks held by kworker/0:11/5554:
#0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc900033bfd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
3 locks held by kworker/1:26/5587:
#0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
#1: ffffc9000352fd00 (fqdir_free_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
#2: ffffffff8c3234b0 (rcu_state.barrier_mutex){+.+.}-{3:3}, at: rcu_barrier+0xa1/0x4c0 kernel/rcu/tree.c:4043
3 locks held by kworker/u4:10/7790:
1 lock held by syz.7.2365/13180:
2 locks held by syz.3.2413/13368:
#0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
#0: ffffffff8d43d408 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3d/0x1b0 drivers/net/tun.c:3440
#1: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#1: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845
2 locks held by syz.7.2415/13378:
#0: ffffffff8c36c228 (event_mutex){+.+.}-{3:3}, at: perf_trace_destroy+0x2a/0x140 kernel/trace/trace_event_perf.c:239
#1: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c3235a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe0f/0xe50 kernel/hung_task.c:369
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 13180 Comm: syz.7.2365 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:202 [inline]
RIP: 0010:arch_atomic_fetch_add_unless include/linux/atomic/atomic-arch-fallback.h:1177 [inline]
RIP: 0010:arch_atomic_add_unless include/linux/atomic/atomic-arch-fallback.h:1197 [inline]
RIP: 0010:atomic_add_unless include/linux/atomic/atomic-instrumented.h:571 [inline]
RIP: 0010:page_ref_add_unless include/linux/page_ref.h:166 [inline]
RIP: 0010:__page_cache_add_speculative include/linux/pagemap.h:238 [inline]
RIP: 0010:page_cache_get_speculative include/linux/pagemap.h:254 [inline]
RIP: 0010:find_get_entry mm/filemap.c:1992 [inline]
RIP: 0010:find_lock_entries+0x22f/0xd70 mm/filemap.c:2092
Code: 0f 85 cb 07 00 00 44 8b 23 31 ff 44 89 e6 e8 c8 5b da ff 45 85 e4 0f 84 3d 07 00 00 41 8d 4c 24 01 31 f6 44 89 e0 f0 0f b1 0b <41> 0f 94 c7 40 0f 94 c6 41 89 c4 bf 02 00 00 00 e8 9c 5a da ff 45
RSP: 0018:ffffc9000360f2e0 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffea0001702bf4 RCX: 0000000000000002
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000360f410 R08: ffffea0001702bf7 R09: 1ffffd40002e057e
R10: dffffc0000000000 R11: fffff940002e057f R12: 0000000000000001
R13: fffffffffffffffe R14: ffffea0001702bc0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fae97d982f8 CR3: 00000000724f0000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000200000000300
DR3: 0000200000000300 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
shmem_undo_range+0x29a/0x1930 mm/shmem.c:943
shmem_truncate_range mm/shmem.c:1063 [inline]
shmem_evict_inode+0x220/0xa40 mm/shmem.c:1145
evict+0x4c9/0x8d0 fs/inode.c:647
__dentry_kill+0x431/0x650 fs/dcache.c:586
dentry_kill+0xb8/0x290 fs/dcache.c:-1
dput+0xd8/0x1a0 fs/dcache.c:893
__fput+0x5ee/0x930 fs/file_table.c:319
task_work_run+0x125/0x1a0 kernel/task_work.c:188
exit_task_work include/linux/task_work.h:33 [inline]
do_exit+0x626/0x20c0 kernel/exit.c:883
do_group_exit+0x12e/0x300 kernel/exit.c:997
get_signal+0x6ca/0x12c0 kernel/signal.c:2900
arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
handle_signal_work kernel/entry/common.c:154 [inline]
exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:320
exc_page_fault+0x88/0x100 arch/x86/mm/fault.c:1499
asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606
RIP: 0033:0x4a
Code: Unable to access opcode bytes at RIP 0x20.
RSP: 002b:00002000000000b8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fae97dc4fa0 RCX: 00007fae97b4b819
RDX: 0000200000000180 RSI: 00002000000000b0 RDI: 0000000000102200
RBP: 00007fae97be1c91 R08: 0000200000000200 R09: 0000200000000200
R10: 00002000000001c0 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fae97dc5038 R14: 00007fae97dc4fa0 R15: 00007fff682b6518