INFO: task syz.0.17:6055 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D
stack:28424 pid:6055 tgid:6053 ppid:5991 task_flags:0x400040 flags:0x00004004
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
io_schedule+0x80/0xd0 kernel/sched/core.c:7906
folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1330
folio_put_wait_locked mm/filemap.c:1494 [inline]
do_read_cache_folio+0x1aa/0x590 mm/filemap.c:3973
read_mapping_folio include/linux/pagemap.h:999 [inline]
erofs_bread+0x46f/0x7f0 fs/erofs/data.c:40
erofs_readdir+0x58a/0x1020 fs/erofs/dir.c:81
iterate_dir+0x399/0x570 fs/readdir.c:108
__do_sys_getdents64 fs/readdir.c:410 [inline]
__se_sys_getdents64+0xe4/0x260 fs/readdir.c:396
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: 0033:0x7fd35198eba9
RSP: 002b:00007fd352810038 EFLAGS: 00000246
ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fd351bd6090 RCX: 00007fd35198eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00007fd351a11e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd351bd6128 R14: 00007fd351bd6090 R15: 00007ffd77f1a8b8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0:
ffffffff8e33c820
(
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
5 locks held by kworker/u8:2/36:
#0: ffff8880b8739f98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:636
#1:
ffff8880b8724008
(
psi_seq
){-.-.}-{0:0}
, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933
#2: ffffffff99f18ff0
(
&obj_hash[i].lock
){-.-.}-{2:2}
, at: lock_timer_base kernel/time/timer.c:1004 [inline]
, at: __mod_timer+0x1ae/0xf30 kernel/time/timer.c:1085
#3:
ffff8880b8724008
(
psi_seq
){-.-.}-{0:0}
, at: debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
#4:
ffffffff8e33c820
(
rcu_read_lock
){....}-{1:3}
, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
3 locks held by kworker/u8:6/2905:
#0:
ffff88801a889148
(
(wq_completion)events_unbound
){+.+.}-{0:0}
, at: process_one_work kernel/workqueue.c:3238 [inline]
, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1:
ffffc9000b207ba0
(
(linkwatch_work).work
){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2:
ffffffff8f740a48
(
rtnl_mutex
){+.+.}-{4:4}
, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
3 locks held by kworker/u8:10/3028:
#0:
ffff88814cb3a948
(
(wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3238 [inline]
(wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3346
#1: ffffc9000b4b7ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3239 [inline]
#1: ffffc9000b4b7ba0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3346
#2: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4194
2 locks held by getty/5630:
#0: ffff88814d03e0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000331e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by syz.0.17/6054:
2 locks held by syz.0.17/6055:
#0: ffff88803233d5f8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff8880582286d0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
6 locks held by syz.1.18/6078:
2 locks held by syz.1.18/6079:
#0: ffff888078034478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff888058229150 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
3 locks held by syz.2.19/6108:
2 locks held by syz.2.19/6109:
#0: ffff88802ed5a478 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff8880610cc6d0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
3 locks held by syz.3.20/6132:
2 locks held by syz.3.20/6133:
#0: ffff88807b2acd38 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff888058229bd0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
3 locks held by syz.4.21/6164:
2 locks held by syz.4.21/6165:
#0: ffff88807802b7b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff8880610cd150 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
3 locks held by syz.5.22/6201:
2 locks held by syz.5.22/6202:
#0: ffff8880784529b8 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x247/0x320 fs/file.c:1232
#1: ffff8880610cdbd0 (&type->i_mutex_dir_key#8){.+.+}-{4:4}, at: iterate_dir+0x292/0x570 fs/readdir.c:101
2 locks held by syz-executor/6205:
#0: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f740a48 (rtnl_mutex){+.+.}-{4:4}, at: rtnetlink_rcv_msg+0x71c/0xb70 net/core/rtnetlink.c:6952
#1: ffffffff8e3422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#1: ffffffff8e3422b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:957
=============================================
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: 6108 Comm: syz.2.19 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 5e ef 6b fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 4f 71 d0 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 1a 1e 32 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900033d6f90 EFLAGS: 00000002
RAX: 1ffffffff3404460 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: ffffffff9a0223b0 R08: ffff888024768237 R09: 1ffff110048ed046
R10: dffffc0000000000 R11: ffffffff8553cbc0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9a022120 R15: 0000000000000000
FS: 00007fd7736836c0(0000) GS:ffff8881259e8000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055dc5c770660 CR3: 0000000078216000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0xd1/0x2f0 drivers/tty/serial/8250/8250_port.c:1961
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3111 [inline]
console_flush_all+0x6f3/0xb10 kernel/printk/printk.c:3199
__console_flush_and_unlock kernel/printk/printk.c:3258 [inline]
console_unlock+0xbb/0x190 kernel/printk/printk.c:3298
vprintk_emit+0x4c5/0x590 kernel/printk/printk.c:2423
_printk+0xcf/0x120 kernel/printk/printk.c:2448
_erofs_printk+0x349/0x410 fs/erofs/super.c:33
z_erofs_readahead+0x726/0xb40 fs/erofs/zdata.c:1919
read_pages+0x17a/0x580 mm/readahead.c:163
page_cache_ra_order+0x922/0xe70 mm/readahead.c:518
page_cache_sync_readahead include/linux/pagemap.h:1377 [inline]
erofs_readdir+0x564/0x1020 fs/erofs/dir.c:77
iterate_dir+0x399/0x570 fs/readdir.c:108
__do_sys_getdents64 fs/readdir.c:410 [inline]
__se_sys_getdents64+0xe4/0x260 fs/readdir.c:396
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: 0033:0x7fd77278eba9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd773683038 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fd7729d5fa0 RCX: 00007fd77278eba9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007fd772811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd7729d6038 R14: 00007fd7729d5fa0 R15: 00007fff97be6ec8