INFO: task syz.4.77:6450 blocked for more than 143 seconds.
Not tainted 6.14.0-rc5-syzkaller-00013-g99fa936e8e4f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.77 state:D stack:27552 pid:6450 tgid:6428 ppid:5822 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x18bc/0x4c40 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]
lock_rename fs/namei.c:3217 [inline]
do_renameat2+0x62c/0x13f0 fs/namei.c:5161
__do_sys_rename fs/namei.c:5273 [inline]
__se_sys_rename fs/namei.c:5271 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:5271
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: 0033:0x7efe4998d169
RSP: 002b:00007efe477f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007efe49ba6160 RCX: 00007efe4998d169
RDX: 0000000000000000 RSI: 0000400000000f40 RDI: 0000400000000600
RBP: 00007efe49a0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007efe49ba6160 R15: 00007ffc631535a8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb38fa0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
3 locks held by kworker/u8:2/35:
4 locks held by kworker/u8:3/53:
#0: ffff888140ea3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888140ea3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319
#1: ffffc90000bd7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000bd7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319
#2: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
#3: ffff88805923afe0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x24a/0x590 fs/jfs/inode.c:102
4 locks held by kworker/u8:4/67:
2 locks held by getty/5579:
#0: ffff888031f260a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fd62f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
3 locks held by kworker/u8:7/5878:
4 locks held by syz.4.77/6449:
2 locks held by syz.4.77/6450:
#0: ffff8880350e4420 (sb_writers#25){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547
#1: ffff88805923b390 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:912 [inline]
#1: ffff88805923b390 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3217 [inline]
#1: ffff88805923b390 (&type->i_mutex_dir_key#15/1){+.+.}-{4:4}, at: do_renameat2+0x62c/0x13f0 fs/namei.c:5161
2 locks held by syz.1.211/7537:
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
2 locks held by syz.1.211/7539:
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
2 locks held by syz.0.284/8406:
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
2 locks held by syz.0.284/8407:
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880350e40e0 (&type->s_umount_key#88){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880254f67d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x26e/0xb50 fs/fs-writeback.c:2819
1 lock held by syz.2.348/8843:
#0: ffffffff8eb3e478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#0: ffffffff8eb3e478 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc5-syzkaller-00013-g99fa936e8e4f #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+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/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: 8843 Comm: syz.2.348 Not tainted 6.14.0-rc5-syzkaller-00013-g99fa936e8e4f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:io_serial_out+0x7e/0xc0 drivers/tty/serial/8250/8250_port.c:416
Code: fc 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 cc 53 aa fc 44 03 3b 44 89 f0 44 89 fa ee <5b> 41 5c 41 5e 41 5f 5d c3 cc cc cc cc 89 e9 80 e1 07 38 c1 7c a7
RSP: 0018:ffffc90004ca72d0 EFLAGS: 00000002
RAX: 000000000000002e RBX: ffffffff9a960e60 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: 0000000000037f23 RDI: 0000000000037f24
RBP: 0000000000000000 R08: ffffffff857c1f0b R09: 1ffff110049c1046
R10: dffffc0000000000 R11: ffffffff857c1ec0 R12: dffffc0000000000
R13: 000000000000002e R14: 000000000000002e R15: 00000000000003f8
FS: 00007f81ae4056c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000400000003a42 CR3: 000000006f8a6000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
serial8250_console_write+0x1430/0x1e00 drivers/tty/serial/8250/8250_port.c:3465
console_emit_next_record kernel/printk/printk.c:3122 [inline]
console_flush_all+0x869/0xeb0 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
_btrfs_printk+0x5ce/0x610 fs/btrfs/messages.c:248
btrfs_emit_options fs/btrfs/super.c:1483 [inline]
btrfs_reconfigure+0x2322/0x2c30 fs/btrfs/super.c:1552
reconfigure_super+0x43a/0x870 fs/super.c:1083
do_remount fs/namespace.c:3100 [inline]
path_mount+0xc22/0xfa0 fs/namespace.c:3879
do_mount fs/namespace.c:3900 [inline]
__do_sys_mount fs/namespace.c:4111 [inline]
__se_sys_mount+0x2d6/0x3c0 fs/namespace.c:4088
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: 0033:0x7f81ad58e90a
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 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:00007f81ae404e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f81ae404ef0 RCX: 00007f81ad58e90a
RDX: 0000400000003a40 RSI: 0000400000000f00 RDI: 0000000000000000
RBP: 0000400000003a40 R08: 00007f81ae404ef0 R09: 0000000001a4a438
R10: 0000000001a4a438 R11: 0000000000000246 R12: 0000400000000f00
R13: 00007f81ae404eb0 R14: 0000000000000000 R15: 0000400000000080