INFO: task syz.3.805:8682 blocked for more than 143 seconds.
Not tainted 6.16.0-rc6-next-20250718-syzkaller #0
Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.805 state:D stack:26920 pid:8682 tgid:8682 ppid:5845 task_flags:0x40044c flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5351 [inline]
__schedule+0x1737/0x4d30 kernel/sched/core.c:6954
__schedule_loop kernel/sched/core.c:7036 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7051
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7108
rwsem_down_read_slowpath+0x5fd/0x8f0 kernel/locking/rwsem.c:1088
__down_read_common kernel/locking/rwsem.c:1263 [inline]
__down_read kernel/locking/rwsem.c:1276 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1541
mmap_read_lock include/linux/mmap_lock.h:412 [inline]
exit_mm+0xcc/0x2c0 kernel/exit.c:557
do_exit+0x648/0x2300 kernel/exit.c:947
do_group_exit+0x21c/0x2d0 kernel/exit.c:1100
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+0x75/0x110 kernel/entry/common.c:40
exit_to_user_mode_prepare include/linux/irq-entry-common.h:208 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb2e7f8e9e3
RSP: 002b:00007ffd27d7eb58 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: fffffffffffffffc RBX: 00007fb2e65f76c0 RCX: 00007fb2e7f8e9e3
RDX: 0000000000000000 RSI: 0000000000021000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00000000ffffffff R09: 0000000000000000
R10: 0000000000020022 R11: 0000000000000246 R12: 00007ffd27d7ecb0
R13: ffffffffffffffc0 R14: 0000000000001000 R15: 0000000000000000
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88801a880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff88801a880d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900000e7bc0 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900000e7bc0 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffffffff8e543338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#2: ffffffff8e543338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967
1 lock held by khungtaskd/31:
#0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e53d8a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
2 locks held by getty/5609:
#0: ffff888033a0d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036c32f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz.1.712/8384:
#0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:634 [inline]
#0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3e/0x1c0 drivers/net/tun.c:3435
1 lock held by syz.3.805/8682:
#0: ffff88807d8d1760 (&mm->mmap_lock){++++}-{4:4}, at: mmap_read_lock include/linux/mmap_lock.h:412 [inline]
#0: ffff88807d8d1760 (&mm->mmap_lock){++++}-{4:4}, at: exit_mm+0xcc/0x2c0 kernel/exit.c:557
1 lock held by syz.3.805/8683:
1 lock held by syz.1.1554/11291:
1 lock held by syz.0.1557/11307:
2 locks held by syz.5.1559/11318:
#0: ffffffff8f938688 (rtnl_mutex){+.+.}-{4:4}, at: ppp_release+0x87/0x1f0 drivers/net/ppp/ppp_generic.c:412
#1: ffffffff8e543338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:343 [inline]
#1: ffffffff8e543338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:967
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 11325 Comm: dhcpcd Not tainted 6.16.0-rc6-next-20250718-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:check_wait_context kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__lock_acquire+0x587/0xd20 kernel/locking/lockdep.c:5190
Code: 24 0f b6 81 c4 00 00 00 84 c0 0f 84 68 ff ff ff 41 0f b6 f4 0f b6 d0 40 38 c6 0f 42 d6 80 b9 c6 00 00 00 02 0f 84 51 ff ff ff <89> d0 e9 4a ff ff ff 48 c7 c7 50 e8 40 8e 48 89 de e8 a3 f8 67 03
RSP: 0018:ffffc900043ff2c8 EFLAGS: 00000093
RAX: 0000000000000004 RBX: 0000000000000000 RCX: ffffffff93916d48
RDX: 0000000000000004 RSI: 0000000000000005 RDI: ffff88802bbe8000
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff822ea7da
R10: dffffc0000000000 R11: ffffed100ea2be02 R12: ffffffffffffff05
R13: 0000000000000001 R14: ffff88802bbe8b68 R15: ffff88802bbe8b10
FS: 00007f4487027740(0000) GS:ffff8881258ab000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4486f9fe9c CR3: 0000000051d2a000 CR4: 00000000003526f0
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock_sched include/linux/rcupdate.h:932 [inline]
pfn_valid+0xd6/0x490 include/linux/mmzone.h:2162
page_table_check_clear+0x21/0x700 mm/page_table_check.c:70
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:725 [inline]
zap_present_folio_ptes mm/memory.c:1505 [inline]
zap_present_ptes mm/memory.c:1587 [inline]
do_zap_pte_range mm/memory.c:1688 [inline]
zap_pte_range mm/memory.c:1732 [inline]
zap_pmd_range mm/memory.c:1824 [inline]
zap_pud_range mm/memory.c:1853 [inline]
zap_p4d_range mm/memory.c:1874 [inline]
unmap_page_range+0x3445/0x4370 mm/memory.c:1895
unmap_single_vma mm/memory.c:1938 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:1982
vms_clear_ptes+0x35c/0x540 mm/vma.c:1228
vms_complete_munmap_vmas+0x206/0x8a0 mm/vma.c:1277
do_vmi_align_munmap+0x358/0x420 mm/vma.c:1536
do_vmi_munmap+0x253/0x2e0 mm/vma.c:1584
__vm_munmap+0x23b/0x3d0 mm/vma.c:3155
__do_sys_munmap mm/mmap.c:1080 [inline]
__se_sys_munmap mm/mmap.c:1077 [inline]
__x64_sys_munmap+0x60/0x70 mm/mmap.c:1077
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f44872362e7
Code: 00 00 00 b8 0a 00 00 00 0f 05 48 3d 01 f0 ff ff 73 01 c3 48 8d 0d c9 3f 01 00 f7 d8 89 01 48 83 c8 ff c3 b8 0b 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8d 0d a9 3f 01 00 f7 d8 89 01 48 83
RSP: 002b:00007ffed3ad8e38 EFLAGS: 00000202 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 000055fecb3a9a10 RCX: 00007f44872362e7
RDX: 0000000000000001 RSI: 0000000000029910 RDI: 00007f4486ff8000
RBP: 00007ffed3ad8f40 R08: 00000000000004f0 R09: 0000000000000002
R10: 00007ffed3ad8d70 R11: 0000000000000202 R12: 00007ffed3ad8e78
R13: 00007f4487249000 R14: 000055fecb3a9a10 R15: 0000000000000000