INFO: task syz.0.8440:5199 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.8440 state:D stack:28296 pid:5199 tgid:5198 ppid:2026 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5264 [inline]
__schedule+0x1848/0x4ec0 kernel/sched/core.c:6872
__schedule_loop kernel/sched/core.c:6954 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6969
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7026
__mutex_lock_common kernel/locking/mutex.c:676 [inline]
__mutex_lock+0x7e6/0x1350 kernel/locking/mutex.c:760
bdev_open+0xe0/0xd30 block/bdev.c:945
blkdev_open+0x457/0x600 block/fops.c:702
do_dentry_open+0x953/0x13f0 fs/open.c:962
vfs_open+0x3b/0x340 fs/open.c:1094
do_open fs/namei.c:3975 [inline]
path_openat+0x2efb/0x3860 fs/namei.c:4134
do_filp_open+0x1fa/0x410 fs/namei.c:4161
do_sys_openat2+0x121/0x1c0 fs/open.c:1434
do_sys_open fs/open.c:1449 [inline]
__do_sys_openat fs/open.c:1465 [inline]
__se_sys_openat fs/open.c:1460 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1460
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: 0033:0x7f138a58df10
RSP: 002b:00007f138b3c7b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000048000 RCX: 00007f138a58df10
RDX: 0000000000048000 RSI: 00007f138b3c7c10 RDI: 00000000ffffff9c
RBP: 00007f138b3c7c10 R08: 0000000000000000 R09: 002364626e2f7665
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f138a7e6038 R14: 00007f138a7e5fa0 R15: 00007fff41769dd8
Showing all locks held in the system:
1 lock held by ksoftirqd/1/23:
1 lock held by khungtaskd/31:
#0: ffffffff8e33d860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e33d860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline]
#0: ffffffff8e33d860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5583:
#0: ffff88814e3180a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/3479:
#0: ffff888141fd2358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz.0.8440/5199:
#0: ffff888141fd2358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30 block/bdev.c:945
1 lock held by syz.6.9475/8754:
#0: ffffffff8e343200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820
1 lock held by syz.9.9478/8768:
#0: ffffffff8e343200 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x570 kernel/rcu/tree.c:3820
5 locks held by dhcpcd-run-hook/8781:
=============================================
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 10/02/2025
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:336 [inline]
watchdog+0xfa9/0xff0 kernel/hung_task.c:499
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x599/0xb30 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: 8784 Comm: dhcpcd-run-hook Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:_compound_head include/linux/page-flags.h:286 [inline]
RIP: 0010:zap_present_ptes mm/memory.c:1695 [inline]
RIP: 0010:do_zap_pte_range mm/memory.c:1814 [inline]
RIP: 0010:zap_pte_range mm/memory.c:1858 [inline]
RIP: 0010:zap_pmd_range mm/memory.c:1950 [inline]
RIP: 0010:zap_pud_range mm/memory.c:1979 [inline]
RIP: 0010:zap_p4d_range mm/memory.c:2000 [inline]
RIP: 0010:unmap_page_range+0xe47/0x4140 mm/memory.c:2021
Code: 00 49 89 c4 4c 8d 78 08 4c 89 f8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 ff e8 6c de 1a 00 4d 8b 3f <4c> 89 fe 48 83 e6 01 31 ff e8 1b a5 b4 ff 4c 89 f8 48 83 e0 01 0f
RSP: 0018:ffffc90004b37600 EFLAGS: 00000246
RAX: 1ffffd400006f931 RBX: 000000000df26025 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 000000000000de00 RDI: 0000000000043a00
RBP: ffffc90004b37890 R08: ffffea000037c9f3 R09: 1ffffd400006f93e
R10: dffffc0000000000 R11: fffff9400006f93f R12: ffffea000037c980
R13: 00007f3ef9f13000 R14: ffff8880673fe898 R15: ffffea000037c9c8
FS: 0000000000000000(0000) GS:ffff888125a83000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3ef9f48368 CR3: 0000000047884000 CR4: 00000000003526f0
Call Trace:
unmap_single_vma mm/memory.c:2064 [inline]
unmap_vmas+0x399/0x580 mm/memory.c:2108
exit_mmap+0x240/0xb40 mm/mmap.c:1277
__mmput+0x118/0x430 kernel/fork.c:1132
exit_mm+0x1da/0x2c0 kernel/exit.c:581
do_exit+0x650/0x2300 kernel/exit.c:958
do_group_exit+0x21c/0x2d0 kernel/exit.c:1111
__do_sys_exit_group kernel/exit.c:1122 [inline]
__se_sys_exit_group kernel/exit.c:1120 [inline]
__x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1120
x64_sys_call+0x2210/0x2210 arch/x86/include/generated/asm/syscalls_64.h:232
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: 0033:0x7f3ef9d786c5
Code: Unable to access opcode bytes at 0x7f3ef9d7869b.
RSP: 002b:00007ffd22f63f08 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007ffd22f64204 RCX: 00007f3ef9d786c5
RDX: 00000000000000e7 RSI: ffffffffffffff88 RDI: 0000000000000000
RBP: 0000000000000003 R08: 00007ffd22f64000 R09: 0000000000000002
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffd22f64240 R14: 00007f3ef9f88000 R15: 0000558d8f21dd98