INFO: task syz.4.182:7466 blocked for more than 143 seconds.
Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.182 state:D stack:18320 pid:7466 tgid:7465 ppid:5836 task_flags:0x400140 flags:0x00000004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_write_slowpath+0xedd/0x1420 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1da/0x220 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:867 [inline]
bch2_write_iter+0x13f/0x2cd0 fs/bcachefs/fs-io-buffered.c:1076
new_sync_write fs/read_write.c:591 [inline]
vfs_write+0x70f/0xd10 fs/read_write.c:684
ksys_pwrite64 fs/read_write.c:791 [inline]
__do_sys_pwrite64 fs/read_write.c:799 [inline]
__se_sys_pwrite64 fs/read_write.c:796 [inline]
__x64_sys_pwrite64+0x1b5/0x250 fs/read_write.c:796
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6b0098e169
RSP: 002b:00007f6b0174a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007f6b00bb5fa0 RCX: 00007f6b0098e169
RDX: 0000000000000004 RSI: 0000200000000080 RDI: 0000000000000005
RBP: 00007f6b00a10a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f6b00bb5fa0 R15: 00007ffd182883c8
</TASK>
Showing all locks held in the system:
3 locks held by kworker/u8:1/13:
#0: ffff88814cdb2148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814cdb2148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc90000127c60 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127c60 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_verify_work+0x19/0x30 net/ipv6/addrconf.c:4735
1 lock held by kdevtmpfs/26:
#0: ffff88801c2e0950 (&type->i_mutex_dir_key/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
#0: ffff88801c2e0950 (&type->i_mutex_dir_key/1){+.+.}-{4:4}, at: __kern_path_locked+0x1ca/0x430 fs/namei.c:2765
1 lock held by khungtaskd/31:
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
5 locks held by kworker/u8:6/1155:
#0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801bef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000388fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000388fc60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffffffff900de750 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x17c/0xd60 net/core/net_namespace.c:608
#3: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xde/0x880 net/core/dev.c:12524
#4: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#4: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998
3 locks held by kworker/u8:7/4351:
#0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801b089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc9000d3e7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000d3e7c60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by udevd/5200:
1 lock held by dhcpcd/5494:
#0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x406/0x1c40 net/ipv4/devinet.c:979
2 locks held by getty/5586:
#0: ffff888031cc60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036d42f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5829:
#0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:633 [inline]
#0: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x3b/0x1b0 drivers/net/tun.c:3390
1 lock held by udevd/6661:
#0: ffff888025807358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xf7/0xcd0 block/bdev.c:907
2 locks held by syz.4.182/7466:
#0: ffff888031106420 (sb_writers#21){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3041 [inline]
#0: ffff888031106420 (sb_writers#21){.+.+}-{0:0}, at: vfs_write+0x23f/0xd10 fs/read_write.c:680
#1: ffff88805bb2b670 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805bb2b670 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: bch2_write_iter+0x13f/0x2cd0 fs/bcachefs/fs-io-buffered.c:1076
5 locks held by syz.4.182/7511:
#0: ffff888031106420 (sb_writers#21){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556
#1: ffff88805bb2b670 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805bb2b670 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: do_truncate+0x20e/0x310 fs/open.c:63
#2: ffff88804a680a70 (&c->snapshot_create_lock){.+.+}-{4:4}, at: bch2_truncate+0x1ae/0x340 fs/bcachefs/io_misc.c:295
#3: ffff88804a684228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff88804a684228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff88804a684228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x7ed/0xd40 fs/bcachefs/btree_iter.c:3382
#4: ffff88804a6a6590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68a/0x16c0 fs/bcachefs/btree_update_interior.c:1179
2 locks held by bch-copygc/loop/7509:
1 lock held by syz.7.371/9236:
#0: ffff888025807358 (&disk->open_mutex){+.+.}-{4:4}, at: loop_reread_partitions drivers/block/loop.c:435 [inline]
#0: ffff888025807358 (&disk->open_mutex){+.+.}-{4:4}, at: loop_set_status+0x7be/0xb20 drivers/block/loop.c:1243
2 locks held by syz-executor/9471:
#0: ffffffff8f87eaa0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f87eaa0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8f87eaa0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:570
#1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4064
2 locks held by syz-executor/9515:
#0: ffffffff8f87eaa0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8f87eaa0 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8f87eaa0 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x22/0x250 net/core/rtnetlink.c:570
#1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#1: ffffffff900eb288 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0xd68/0x1fe0 net/core/rtnetlink.c:4064
3 locks held by syz.1.473/9900:
2 locks held by modprobe/9920:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:437
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5827 Comm: syz-executor Not tainted 6.15.0-rc2-syzkaller-00471-g119009db2674 #0 PREEMPT(full)
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: 30 07 34 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 81 b5 9b fc 44 03 33 44 89 f2 ec <0f> b6 c0 5b 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c
RSP: 0018:ffffc90003ecf478 EFLAGS: 00000002
RAX: 1ffffffff3548f00 RBX: ffffffff9aa47960 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff858eb526 R09: 1ffff11004a1b046
R10: dffffc0000000000 R11: ffffffff858eb4e0 R12: 0000000000000020
R13: 1ffffffff3548f7e R14: 00000000000003fd R15: dffffc0000000000
FS: 000055558ed46500(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9f16de9dce CR3: 000000006091a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
serial_in drivers/tty/serial/8250/8250.h:137 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline]
wait_for_lsr+0x1b1/0x320 drivers/tty/serial/8250/8250_port.c:2098
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline]
serial8250_console_write+0x1350/0x1e00 drivers/tty/serial/8250/8250_port.c:3456
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x86b/0xec0 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0x151/0x3b0 kernel/printk/printk.c:3325
vprintk_emit+0x761/0xa40 kernel/printk/printk.c:2450
_printk+0xd5/0x120 kernel/printk/printk.c:2475
__xfs_printk fs/xfs/xfs_message.c:24 [inline]
xfs_printk_level+0x1cc/0x320 fs/xfs/xfs_message.c:44
xfs_fs_put_super+0x55/0x160 fs/xfs/xfs_super.c:1232
generic_shutdown_super+0x139/0x2d0 fs/super.c:642
kill_block_super+0x44/0x90 fs/super.c:1710
xfs_kill_sb+0x15/0x50 fs/xfs/xfs_super.c:2220
deactivate_locked_super+0xc4/0x130 fs/super.c:473
cleanup_mnt+0x422/0x4c0 fs/namespace.c:1435
task_work_run+0x251/0x310 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop kernel/entry/common.c:114 [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+0x13f/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f516818f497
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc0c0c5708 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f5168210854 RCX: 00007f516818f497
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc0c0c57c0
RBP: 00007ffc0c0c57c0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc0c0c6850
R13: 00007f5168210854 R14: 0000000000055460 R15: 00007ffc0c0c6890
</TASK>