INFO: task syz.6.2548:14795 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.2548 state:D stack:25608 pid:14795 tgid:14795 ppid:14188 task_flags:0x400040 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5360 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
__schedule_loop kernel/sched/core.c:7046 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7061
request_wait_answer fs/fuse/dev.c:567 [inline]
__fuse_request_send fs/fuse/dev.c:581 [inline]
__fuse_simple_request+0xf15/0x18d0 fs/fuse/dev.c:675
fuse_simple_request fs/fuse/fuse_i.h:1250 [inline]
fuse_flush+0x5d4/0x800 fs/fuse/file.c:476
filp_flush+0xbd/0x190 fs/open.c:1547
filp_close+0x1d/0x40 fs/open.c:1560
__range_close fs/file.c:767 [inline]
__do_sys_close_range fs/file.c:826 [inline]
__se_sys_close_range+0x359/0x650 fs/file.c:790
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f81d618eba9
RSP: 002b:00007fff2fd56b38 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: ffffffffffffffda RBX: 00007f81d63d7da0 RCX: 00007f81d618eba9
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007f81d63d7da0 R08: 00000000000000a0 R09: 0000000a2fd56e2f
R10: 00007f81d63d7cb0 R11: 0000000000000246 R12: 00000000000923d0
R13: 00007f81d63d6090 R14: ffffffffffffffff R15: 00007fff2fd56c50
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e53c820 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e53c820 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e53c820 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5620:
#0: ffff88814cd9c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz-executor/17748:
#0: ffffffff8f0c4220 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f0c4220 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8f0c4220 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
#1: ffffffff8f955108 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff8f955108 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff8f955108 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4056
#2: ffffffff8e5422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e5422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
2 locks held by syz.2.3695/17834:
#0: ffffffff8f948270 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x304/0x4d0 net/core/net_namespace.c:566
#1: ffffffff8f955108 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:332 [inline]
watchdog+0xf60/0xfa0 kernel/hung_task.c:495
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17828 Comm: syz.2.3693 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:__read_once_word_nocheck+0x0/0x10 include/asm-generic/rwonce.h:67
Code: e8 c5 51 b0 00 48 ba 00 00 00 00 00 fc ff df e9 88 fc ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <48> 8b 07 e9 18 2e 1a 0a cc cc cc cc cc cc cc cc 90 90 90 90 90 90
RSP: 0018:ffffc9000e19ed30 EFLAGS: 00000202
RAX: ffffc9000e19ee01 RBX: ffffc9000e19ee60 RCX: 1ffff92001c33d01
RDX: ffffffff90761992 RSI: 0000000000000002 RDI: ffffc9000e19ee60
RBP: 1ffff92001c33dce R08: 0000000000000009 R09: ffffffff81740d25
R10: ffffc9000e19ee68 R11: fffff52001c33dd9 R12: ffffc9000e1a0000
R13: 1ffff92001c33dcf R14: ffffc9000e19ee68 R15: ffffc9000e198000
FS: 0000000000000000(0000) GS:ffff8881257a7000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055555f9a35c8 CR3: 0000000078106000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000009292 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline]
unwind_next_frame+0xc3c/0x2390 arch/x86/kernel/unwind_orc.c:585
__unwind_start+0x5b9/0x760 arch/x86/kernel/unwind_orc.c:758
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xe4/0x150 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf5/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x71/0x1f0 mm/page_owner.c:308
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1394 [inline]
free_unref_folios+0xdb3/0x14f0 mm/page_alloc.c:2963
folios_put_refs+0x584/0x670 mm/swap.c:1002
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1120
shmem_truncate_range mm/shmem.c:1232 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1360
evict+0x504/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
__fput+0x68e/0xa70 fs/file_table.c:476
task_work_run+0x1d4/0x260 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0x6b5/0x2300 kernel/exit.c:966
do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
get_signal+0x1286/0x1340 kernel/signal.c:3034
arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:40 [inline]
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
irqentry_exit_to_user_mode+0x81/0x120 kernel/entry/common.c:73
exc_page_fault+0xab/0x100 arch/x86/mm/fault.c:1535
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fd7cc38ebb1
Code: Unable to access opcode bytes at 0x7fd7cc38eb87.
RSP: 002b:0000000000000050 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007fd7cc5d5fa0 RCX: 00007fd7cc38eba9
RDX: 0000000000000000 RSI: 0000000000000050 RDI: 0000000000904000
RBP: 00007fd7cc411e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fd7cc5d6038 R14: 00007fd7cc5d5fa0 R15: 00007ffc9e658848