INFO: task syz.2.1660:11903 blocked for more than 143 seconds.
Not tainted 5.15.163-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1660 state:D stack:27520 pid:11903 ppid: 10683 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
rwsem_down_write_slowpath+0xf0c/0x16a0 kernel/locking/rwsem.c:1165
inode_lock_nested include/linux/fs.h:824 [inline]
do_unlinkat+0x266/0x950 fs/namei.c:4331
__do_sys_unlink fs/namei.c:4396 [inline]
__se_sys_unlink fs/namei.c:4394 [inline]
__x64_sys_unlink+0x45/0x50 fs/namei.c:4394
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f93e7848b59
RSP: 002b:00007f93e62a8048 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007f93e79d9038 RCX: 00007f93e7848b59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000020000040
RBP: 00007f93e78b7e5d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000006e R14: 00007f93e79d9038 R15: 00007ffe0e974618
Showing all locks held in the system:
2 locks held by kworker/u4:0/9:
1 lock held by khungtaskd/27:
#0: ffffffff8c91fb20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by getty/3262:
#0: ffff88802437e098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc9000209b2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
2 locks held by kworker/1:4/3551:
#0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900030b7d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
3 locks held by kworker/0:6/3553:
#0: ffff88802317a938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900030e7d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4112
3 locks held by kworker/0:8/3583:
#0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003157d20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
2 locks held by kworker/0:15/4491:
#0: ffff888011c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003447d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
2 locks held by kworker/0:16/4492:
#0: ffff888011c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003457d20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
3 locks held by kworker/1:22/6454:
#0: ffff88802317a938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900034a7d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4112
3 locks held by syz.2.1660/11880:
2 locks held by syz.2.1660/11903:
#0: ffff88801cf0c460 (sb_writers#37){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:377
#1: ffff88805640c188 (&type->i_mutex_dir_key#26/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:824 [inline]
#1: ffff88805640c188 (&type->i_mutex_dir_key#26/1){+.+.}-{3:3}, at: do_unlinkat+0x266/0x950 fs/namei.c:4331
5 locks held by kworker/u4:6/12022:
#0: ffff888011dcd138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003267d20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8d9dc790 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:561
#3: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0xc0/0x460 net/ipv6/ip6_gre.c:1647
#4: ffffffff8c9240e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#4: ffffffff8c9240e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845
2 locks held by syz-executor/13266:
#0: ffff8880773e60e0 (&type->s_umount_key#79){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
#1: ffffffff8c9240e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8c9240e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845
1 lock held by syz-executor/14044:
#0: ffff88807b3ec0e0 (&type->s_umount_key#79){++++}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
1 lock held by syz.1.2120/14106:
#0: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: tun_detach drivers/net/tun.c:699 [inline]
#0: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: tun_chr_close+0x3a/0x1b0 drivers/net/tun.c:3437
1 lock held by syz-executor/14254:
#0: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9e8348 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5626
2 locks held by syz.0.2137/14291:
#0: ffff88801b104118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
#1: ffff888147546468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.163-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 14291 Comm: syz.0.2137 Not tainted 5.15.163-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
RIP: 0010:io_serial_out+0x7a/0xb0 drivers/tty/serial/8250/8250_port.c:468
Code: fd 89 e9 41 d3 e7 48 83 c3 40 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 80 51 4f fd 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 89 e9 80 e1 07 38 c1 7c ab 48 89 ef e8
RSP: 0018:ffffc900037270a8 EFLAGS: 00000002
RAX: 0000000000000020 RBX: ffffffff9171a780 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 000000000000b75b RDI: 000000000000b75c
RBP: 0000000000000000 R08: ffffffff847adef7 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: dffffc0000000000
R13: ffffffff914349c0 R14: 0000000000000020 R15: 00000000000003f8
FS: 00007f084efca6c0(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0847ba9000 CR3: 0000000078db5000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
uart_console_write+0xa9/0x100 drivers/tty/serial/serial_core.c:1971
serial8250_console_write+0xc8e/0x1180 drivers/tty/serial/8250/8250_port.c:3378
console_unlock+0xced/0x12b0 kernel/printk/printk.c:2744
vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
_printk+0xd1/0x120 kernel/printk/printk.c:2299
device_list_add+0x1450/0x1e20 fs/btrfs/volumes.c:920
btrfs_scan_one_device+0x436/0x690 fs/btrfs/volumes.c:1452
btrfs_mount_root+0x4b4/0x930 fs/btrfs/super.c:1716
legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
vfs_get_tree+0x88/0x270 fs/super.c:1517
fc_mount fs/namespace.c:1000 [inline]
vfs_kern_mount+0xb8/0x150 fs/namespace.c:1030
btrfs_mount+0x395/0xb40 fs/btrfs/super.c:1812
legacy_get_tree+0xeb/0x180 fs/fs_context.c:611
vfs_get_tree+0x88/0x270 fs/super.c:1517
do_new_mount+0x2ba/0xb40 fs/namespace.c:3005
do_mount fs/namespace.c:3348 [inline]
__do_sys_mount fs/namespace.c:3556 [inline]
__se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3533
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f085056c25a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 7e 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 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:00007f084efc9e78 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f084efc9f00 RCX: 00007f085056c25a
RDX: 0000000020000100 RSI: 0000000020005140 RDI: 00007f084efc9ec0
RBP: 0000000020000100 R08: 00007f084efc9f00 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000020005140
R13: 00007f084efc9ec0 R14: 00000000000050ed R15: 0000000020000200