INFO: task syz.8.1568:14590 blocked for more than 143 seconds.
Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1568 state:D stack:27552 pid:14590 tgid:14583 ppid:6579 task_flags:0x400140 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x190e/0x4c90 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1e0/0x220 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:912 [inline]
filename_create+0x260/0x540 fs/namei.c:4082
do_mkdirat+0xbd/0x3a0 fs/namei.c:4328
__do_sys_mkdirat fs/namei.c:4351 [inline]
__se_sys_mkdirat fs/namei.c:4349 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4349
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f744cf8b9d7
RSP: 002b:00007f744dea9e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f744dea9ef0 RCX: 00007f744cf8b9d7
RDX: 00000000000001ff RSI: 0000200000000680 RDI: 00000000ffffff9c
RBP: 0000200000000040 R08: 0000200000000040 R09: 0000000000000000
R10: 0000200000000040 R11: 0000000000000246 R12: 0000200000000680
R13: 00007f744dea9eb0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
3 locks held by kworker/0:2/969:
4 locks held by kworker/u8:7/3444:
1 lock held by dhcpcd/5497:
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: devinet_ioctl+0x34c/0x1d80 net/ipv4/devinet.c:1129
2 locks held by getty/5587:
#0: ffff888035dea0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:16/13302:
2 locks held by syz.8.1568/14584:
2 locks held by syz.8.1568/14590:
#0: ffff8880778cc420 (sb_writers#42){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547
#1: ffff888054858180 (&type->i_mutex_dir_key#30/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:912 [inline]
#1: ffff888054858180 (&type->i_mutex_dir_key#30/1){+.+.}-{4:4}, at: filename_create+0x260/0x540 fs/namei.c:4082
1 lock held by syz-executor/15884:
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
3 locks held by kworker/u8:20/16103:
#0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b081148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc90004b7fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90004b7fc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:285
2 locks held by syz.5.1876/16164:
#0: ffffffff903ee318 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff903ee318 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff903ee318 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:564
#1: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:335 [inline]
#1: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xc55/0x1d30 net/core/rtnetlink.c:4021
2 locks held by syz.9.1878/16163:
#0: ffff888056c13e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
#0: ffff888056c13e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff888056c13e08 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x90/0x240 net/socket.c:1398
#1: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#1: ffffffff8eb3e8b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
1 lock held by syz.4.1877/16166:
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:129 [inline]
#0: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: dev_ioctl+0x86e/0x1340 net/core/dev_ioctl.c:852
3 locks held by syz.0.1880/16173:
#0: ffffffff9aa12b98 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:164 [inline]
#0: ffffffff9aa12b98 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline]
#0: ffffffff9aa12b98 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x32d/0x9e0 drivers/infiniband/core/netlink.c:259
#1: ffffffff8fc59eb0 (link_ops_rwsem){++++}-{4:4}, at: nldev_newlink+0x454/0x680 drivers/infiniband/core/nldev.c:1785
#2: ffffffff8fed5f48 (rtnl_mutex){+.+.}-{4:4}, at: ib_get_eth_speed+0x153/0x800 drivers/infiniband/core/verbs.c:1995
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7ab/0x920 kernel/kthread.c:464
ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 16163 Comm: syz.9.1878 Not tainted 6.14.0-rc7-syzkaller-00196-g88d324e69ea9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:io_serial_in+0x76/0xb0 drivers/tty/serial/8250/8250_port.c:409
Code: a0 7f 3d fc 89 e9 41 d3 e6 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 38 00 74 08 48 89 df e8 11 bf a4 fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d e9 a7 e0 8b fb 89 e9 80 e1 07 38 c1 7c
RSP: 0018:ffffc90004b6eff8 EFLAGS: 00000002
RAX: 1ffffffff3533400 RBX: ffffffff9a99a100 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff85846026 R09: 1ffff110049b3046
R10: dffffc0000000000 R11: ffffffff85845fe0 R12: 0000000000000020
R13: 1ffffffff3533472 R14: 00000000000003fd R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555584e245c8 CR3: 0000000032ba6000 CR4: 0000000000350ef0
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+0x1b3/0x320 drivers/tty/serial/8250/8250_port.c:2100
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3357 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3380 [inline]
serial8250_console_write+0x134c/0x1e00 drivers/tty/serial/8250/8250_port.c:3465
console_emit_next_record kernel/printk/printk.c:3122 [inline]
console_flush_all+0x86b/0xeb0 kernel/printk/printk.c:3210
__console_flush_and_unlock kernel/printk/printk.c:3269 [inline]
console_unlock+0x14f/0x3b0 kernel/printk/printk.c:3309
vprintk_emit+0x730/0xa10 kernel/printk/printk.c:2432
_printk+0xd5/0x120 kernel/printk/printk.c:2457
__ext4_msg+0x2db/0x2f0 fs/ext4/super.c:998
ext4_put_super+0xc5/0xd10 fs/ext4/super.c:1303
generic_shutdown_super+0x13b/0x2d0 fs/super.c:642
kill_block_super+0x44/0x90 fs/super.c:1710
ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7368
deactivate_locked_super+0xc6/0x130 fs/super.c:473
cleanup_mnt+0x41f/0x4b0 fs/namespace.c:1413
task_work_run+0x251/0x310 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa2a/0x2940 kernel/exit.c:938
do_group_exit+0x207/0x2c0 kernel/exit.c:1087
get_signal+0x168c/0x1720 kernel/signal.c:3036
arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcb14b8cd6b
Code: Unable to access opcode bytes at 0x7fcb14b8cd41.
RSP: 002b:00007fcb149f6f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 0000000000000007 RCX: 00007fcb14b8cd6b
RDX: 00007fcb149f7fe0 RSI: 0000000080085502 RDI: 0000000000000007
RBP: 00007fcb149f7fe0 R08: 0000000000000080 R09: 00007fcb149f6fd8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 0000000000000008 R15: 00007fcb14c18e4e