INFO: task syz.7.236:8239 blocked for more than 143 seconds.
Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.236 state:D stack:26760 pid:8239 tgid:8228 ppid:7751 task_flags:0x400040 flags:0x00000004
Call Trace:
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_nested+0x1e2/0x220 kernel/locking/rwsem.c:1694
vfs_rename+0x686/0xf10 fs/namei.c:5057
do_renameat2+0xc8d/0x1290 fs/namei.c:5235
__do_sys_rename fs/namei.c:5282 [inline]
__se_sys_rename fs/namei.c:5280 [inline]
__x64_sys_rename+0x82/0x90 fs/namei.c:5280
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: 0033:0x7f69f5b8e169
RSP: 002b:00007f69f6975038 EFLAGS: 00000246 ORIG_RAX: 0000000000000052
RAX: ffffffffffffffda RBX: 00007f69f5db6160 RCX: 00007f69f5b8e169
RDX: 0000000000000000 RSI: 0000200000000100 RDI: 00002000000000c0
RBP: 00007f69f5c10a68 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f69f5db6160 R15: 00007ffc5560be98
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
2 locks held by kworker/u8:1/13:
#0: ffff8881452bc148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8881452bc148 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc90000127c60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127c60 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
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
4 locks held by kworker/u8:2/36:
#0: ffff88801f6fa148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801f6fa148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc90000ad7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000ad7c60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff8880132740e0 (&type->s_umount_key#79){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
#3: ffff8880587f93b0 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_down_write fs/f2fs/f2fs.h:2213 [inline]
#3: ffff8880587f93b0 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_balance_fs+0x636/0x8c0 fs/f2fs/segment.c:454
2 locks held by kworker/u8:3/53:
2 locks held by getty/5591:
#0: ffff8880368f90a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000364b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
5 locks held by syz.7.236/8230:
3 locks held by syz.7.236/8239:
#0: ffff888013274420 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556
#1: ffff88805aadadf8 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
#1: ffff88805aadadf8 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: lock_rename fs/namei.c:3230 [inline]
#1: ffff88805aadadf8 (&type->i_mutex_dir_key#17/1){+.+.}-{4:4}, at: do_renameat2+0x633/0x1290 fs/namei.c:5181
#2: ffff88807cf81328 (&sb->s_type->i_mutex_key#26/4){+.+.}-{4:4}, at: vfs_rename+0x686/0xf10 fs/namei.c:5057
5 locks held by syz.6.322/9559:
#0: ffff88805d5e4420 (sb_writers#26){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:556
#1: ffff88805aa75c68 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88805aa75c68 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: open_last_lookups fs/namei.c:3762 [inline]
#1: ffff88805aa75c68 (&sb->s_type->i_mutex_key#31){++++}-{4:4}, at: path_openat+0x8af/0x35d0 fs/namei.c:4001
#2: ffff88805aa76050 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x359/0xf40 fs/bcachefs/fs.c:550
#3: ffff888071e84228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888071e84228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888071e84228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: bch2_trans_srcu_lock+0x9a/0x1a0 fs/bcachefs/btree_iter.c:3199
#4: ffff888071ea6590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68a/0x16c0 fs/bcachefs/btree_update_interior.c:1179
3 locks held by bch-copygc/loop/9633:
1 lock held by syz-executor/9880:
#0: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998
2 locks held by syz.1.362/9951:
#0: ffff8880132740e0 (&type->s_umount_key#79){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff8880132740e0 (&type->s_umount_key#79){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff888025a8e7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888025a8e7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x270/0xb50 fs/fs-writeback.c:2831
2 locks held by syz.2.425/10582:
#0: ffff8880606b60e0 (&type->s_umount_key#78/1){+.+.}-{4:4}, at: alloc_super+0x221/0x9d0 fs/super.c:344
#1: ffffffff8ed43300 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774
2 locks held by syz.3.426/10591:
#0: ffff888069de20e0 (&type->s_umount_key#78/1){+.+.}-{4:4}, at: alloc_super+0x221/0x9d0 fs/super.c:344
#1: ffffffff8ed43300 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3774
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #0 PREEMPT(full)
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+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
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8419 Comm: syz-executor Not tainted 6.15.0-rc2-syzkaller-00400-g3088d26962e8 #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: d0 0b 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 21 ba 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:ffffc9000b3e7438 EFLAGS: 00000002
RAX: 1ffffffff3548f00 RBX: ffffffff9aa47960 RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: 0000000000000000 R08: ffffffff858eaf66 R09: 1ffff11004a89046
R10: dffffc0000000000 R11: ffffffff858eaf20 R12: 0000000000000020
R13: 1ffffffff3548f7e R14: 00000000000003fd R15: dffffc0000000000
FS: 00005555758af500(0000) GS:ffff888124fcf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055e2c039a000 CR3: 000000006ac88000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
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+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
_btrfs_printk+0x5d1/0x620 fs/btrfs/messages.c:248
btrfs_put_super+0x69/0x80 fs/btrfs/super.c:73
generic_shutdown_super+0x139/0x2d0 fs/super.c:642
kill_anon_super+0x3b/0x70 fs/super.c:1237
btrfs_kill_super+0x41/0x50 fs/btrfs/super.c:2099
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: 0033:0x7f0343b8f497
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:00007ffe3ab7b978 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f0343c10854 RCX: 00007f0343b8f497
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3ab7ba30
RBP: 00007ffe3ab7ba30 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe3ab7cac0
R13: 00007f0343c10854 R14: 000000000005f264 R15: 00007ffe3ab7cb00