INFO: task kworker/u8:2:5720 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:2 state:D stack:23456 pid:5720 tgid:5720 ppid:2 task_flags:0x4208060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-btrfs-1)
Call Trace:
context_switch kernel/sched/core.c:5402 [inline]
__schedule+0x16f9/0x5500 kernel/sched/core.c:7204
__schedule_loop kernel/sched/core.c:7283 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7298
wait_extent_bit fs/btrfs/extent-io-tree.c:905 [inline]
btrfs_lock_extent_bits+0x59c/0x700 fs/btrfs/extent-io-tree.c:2008
btrfs_lock_extent fs/btrfs/extent-io-tree.h:152 [inline]
btrfs_invalidate_folio+0x440/0xc00 fs/btrfs/inode.c:7718
extent_writepage fs/btrfs/extent_io.c:1848 [inline]
extent_write_cache_pages fs/btrfs/extent_io.c:2552 [inline]
btrfs_writepages+0x12f3/0x2410 fs/btrfs/extent_io.c:2684
do_writepages+0x32e/0x550 mm/page-writeback.c:2571
__writeback_single_inode+0x133/0x10e0 fs/fs-writeback.c:1764
writeback_sb_inodes+0x97f/0x1980 fs/fs-writeback.c:2056
wb_writeback+0x445/0xb00 fs/fs-writeback.c:2241
wb_do_writeback fs/fs-writeback.c:2388 [inline]
wb_workfn+0x3fd/0xf20 fs/fs-writeback.c:2428
process_one_work+0x98b/0x1630 kernel/workqueue.c:3318
process_scheduled_works kernel/workqueue.c:3401 [inline]
worker_thread+0xb49/0x1140 kernel/workqueue.c:3482
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.0.17:6014 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:22904 pid:6014 tgid:6013 ppid:5860 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5402 [inline]
__schedule+0x16f9/0x5500 kernel/sched/core.c:7204
__schedule_loop kernel/sched/core.c:7283 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7298
wb_wait_for_completion+0x3e8/0x790 fs/fs-writeback.c:227
__writeback_inodes_sb_nr+0x24c/0x2d0 fs/fs-writeback.c:2847
try_to_writeback_inodes_sb+0x9a/0xc0 fs/fs-writeback.c:2895
btrfs_start_delalloc_flush fs/btrfs/transaction.c:2182 [inline]
btrfs_commit_transaction+0x813/0x2fc0 fs/btrfs/transaction.c:2371
btrfs_sync_file+0xdf4/0x1230 fs/btrfs/file.c:1822
generic_write_sync include/linux/fs.h:2663 [inline]
btrfs_do_write_iter+0x6a9/0x840 fs/btrfs/file.c:1473
new_sync_write fs/read_write.c:595 [inline]
vfs_write+0x629/0xba0 fs/read_write.c:688
ksys_write+0x156/0x270 fs/read_write.c:740
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f74eb26ce59
RSP: 002b:00007f74ea8c6028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f74eb4e5fa0 RCX: 00007f74eb26ce59
RDX: 000000000000029f RSI: 0000200000000200 RDI: 0000000000000004
RBP: 00007f74eb302d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f74eb4e6038 R14: 00007f74eb4e5fa0 R15: 00007fff73529d88
INFO: task syz.0.17:6032 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17 state:D stack:20832 pid:6032 tgid:6013 ppid:5860 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5402 [inline]
__schedule+0x16f9/0x5500 kernel/sched/core.c:7204
__schedule_loop kernel/sched/core.c:7283 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7298
wait_current_trans+0x39f/0x590 fs/btrfs/transaction.c:536
start_transaction+0xbd8/0x1820 fs/btrfs/transaction.c:716
clone_copy_inline_extent fs/btrfs/reflink.c:299 [inline]
btrfs_clone+0x1316/0x2540 fs/btrfs/reflink.c:574
btrfs_clone_files+0x271/0x3f0 fs/btrfs/reflink.c:795
btrfs_remap_file_range+0x76b/0x1320 fs/btrfs/reflink.c:948
vfs_clone_file_range+0x435/0x7b0 fs/remap_range.c:403
ioctl_file_clone fs/ioctl.c:239 [inline]
ioctl_file_clone_range fs/ioctl.c:257 [inline]
do_vfs_ioctl+0xe15/0x1540 fs/ioctl.c:544
__do_sys_ioctl fs/ioctl.c:595 [inline]
__se_sys_ioctl+0x82/0x170 fs/ioctl.c:583
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f74eb26ce59
RSP: 002b:00007f74ea8a5028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f74eb4e6090 RCX: 00007f74eb26ce59
RDX: 00002000000000c0 RSI: 000000004020940d RDI: 0000000000000004
RBP: 00007f74eb302d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f74eb4e6128 R14: 00007f74eb4e6090 R15: 00007fff73529d88
Showing all locks held in the system:
4 locks held by pr/legacy/17:
#0: ffffffff8dfbce40 (console_lock){+.+.}-{0:0}, at: legacy_kthread_func+0x1a3/0x250 kernel/printk/printk.c:3711
#1: ffffffff8dea4738 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:305 [inline]
#1: ffffffff8dea4738 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:428 [inline]
#1: ffffffff8dea4738 (console_srcu){....}-{0:0}, at: console_srcu_read_lock kernel/printk/printk.c:291 [inline]
#1: ffffffff8dea4738 (console_srcu){....}-{0:0}, at: console_flush_one_record+0xfa/0xb90 kernel/printk/printk.c:3246
#2: ffffffff99ba1f78 (&port_lock_key){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#2: ffffffff99ba1f78 (&port_lock_key){+.+.}-{3:3}, at: uart_port_lock_irqsave include/linux/serial_core.h:719 [inline]
#2: ffffffff99ba1f78 (&port_lock_key){+.+.}-{3:3}, at: serial8250_console_write+0x179/0x1b90 drivers/tty/serial/8250/8250_port.c:3321
#3: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#3: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#3: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#3: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1e0/0x400 kernel/locking/spinlock_rt.c:57
1 lock held by khungtaskd/39:
#0: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffffffff8dfcabc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6777
2 locks held by kworker/u8:13/1319:
#0: ffff88801eefd138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293
#1: ffffc900067f7c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294
1 lock held by klogd/4970:
#0: ffff8880b8641c78 (_T->lock){....}-{2:2}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffff8880b8641c78 (_T->lock){....}-{2:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
#0: ffff8880b8641c78 (_T->lock){....}-{2:2}, at: sock_def_readable+0xae/0x550 net/core/sock.c:3614
2 locks held by getty/5366:
#0: ffff88803614c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cd32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13a0 drivers/tty/n_tty.c:2211
2 locks held by kworker/u8:2/5720:
#0: ffff88801eefd138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x897/0x1630 kernel/workqueue.c:3293
#1: ffffc90004fdfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x8be/0x1630 kernel/workqueue.c:3294
6 locks held by syz.0.17/6014:
#0: ffff888036bacd28 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1260
#1: ffff888025dac480 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888025dac480 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
#2: ffff888025dac770 (sb_internal#2){.+.+}-{0:0}, at: btrfs_sync_file+0xcae/0x1230 fs/btrfs/file.c:1729
#3: ffff888037ea3110 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x612/0xd50 fs/btrfs/transaction.c:299
#4: ffff888037ea3138 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x612/0xd50 fs/btrfs/transaction.c:299
#5: ffff888025dac0d0 (&type->s_umount_key#55){++++}-{4:4}, at: try_to_writeback_inodes_sb+0x22/0xc0 fs/fs-writeback.c:2892
4 locks held by syz.0.17/6032:
#0: ffff888025dac480 (sb_writers#12){.+.+}-{0:0}, at: ioctl_file_clone fs/ioctl.c:239 [inline]
#0: ffff888025dac480 (sb_writers#12){.+.+}-{0:0}, at: ioctl_file_clone_range fs/ioctl.c:257 [inline]
#0: ffff888025dac480 (sb_writers#12){.+.+}-{0:0}, at: do_vfs_ioctl+0xe15/0x1540 fs/ioctl.c:544
#1: ffff88803fc9ec78 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#1: ffff88803fc9ec78 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: btrfs_inode_lock+0x51/0xe0 fs/btrfs/inode.c:368
#2: ffff88803fc9ead8 (&ei->i_mmap_lock){+.+.}-{4:4}, at: btrfs_inode_lock+0xcb/0xe0 fs/btrfs/inode.c:371
#3: ffff888025dac770 (sb_internal#2){.+.+}-{0:0}, at: clone_copy_inline_extent fs/btrfs/reflink.c:299 [inline]
#3: ffff888025dac770 (sb_internal#2){.+.+}-{0:0}, at: btrfs_clone+0x1316/0x2540 fs/btrfs/reflink.c:574
1 lock held by btrfs-transacti/6029:
#0: ffff888037ea0d98 (&fs_info->transaction_kthread_mutex){+.+.}-{4:4}, at: transaction_kthread+0xe6/0x450 fs/btrfs/disk-io.c:1521
1 lock held by udevd/6072:
#0: ffff888021b4ba30 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#0: ffff888021b4ba30 (&mm->mmap_lock){++++}-{4:4}, at: do_mprotect_pkey+0x25b/0xd20 mm/mprotect.c:867
6 locks held by syz.1.107/7548:
#0: ffff88803bf1a128 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x252/0x320 fs/file.c:1260
#1: ffff888037a50480 (sb_writers#12){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
#1: ffff888037a50480 (sb_writers#12){.+.+}-{0:0}, at: vfs_write+0x22d/0xba0 fs/read_write.c:684
#2: ffff888037a50770 (sb_internal#2){.+.+}-{0:0}, at: btrfs_sync_file+0xcae/0x1230 fs/btrfs/file.c:1729
#3: ffff88803b9c7110 (btrfs_trans_num_writers){++++}-{0:0}, at: join_transaction+0x612/0xd50 fs/btrfs/transaction.c:299
#4: ffff88803b9c7138 (btrfs_trans_num_extwriters){++++}-{0:0}, at: join_transaction+0x612/0xd50 fs/btrfs/transaction.c:299
#5: ffff888037a500d0 (&type->s_umount_key#55){++++}-{4:4}, at: try_to_writeback_inodes_sb+0x22/0xc0 fs/fs-writeback.c:2892
4 locks held by syz.1.107/7565:
#0: ffff888037a50480 (sb_writers#12){.+.+}-{0:0}, at: ioctl_file_clone fs/ioctl.c:239 [inline]
#0: ffff888037a50480 (sb_writers#12){.+.+}-{0:0}, at: ioctl_file_clone_range fs/ioctl.c:257 [inline]
#0: ffff888037a50480 (sb_writers#12){.+.+}-{0:0}, at: do_vfs_ioctl+0xe15/0x1540 fs/ioctl.c:544
#1: ffff88804428ec78 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1024 [inline]
#1: ffff88804428ec78 (&sb->s_type->i_mutex_key#24){+.+.}-{4:4}, at: btrfs_inode_lock+0x51/0xe0 fs/btrfs/inode.c:368
#2: ffff88804428ead8 (&ei->i_mmap_lock){+.+.}-{4:4}, at: btrfs_inode_lock+0xcb/0xe0 fs/btrfs/inode.c:371
#3: ffff888037a50770 (sb_internal#2){.+.+}-{0:0}, at: clone_copy_inline_extent fs/btrfs/reflink.c:299 [inline]
#3: ffff888037a50770 (sb_internal#2){.+.+}-{0:0}, at: btrfs_clone+0x1316/0x2540 fs/btrfs/reflink.c:574
1 lock held by btrfs-transacti/7562:
#0: ffff88803b9c4d98 (&fs_info->transaction_kthread_mutex){+.+.}-{4:4}, at: transaction_kthread+0xe6/0x450 fs/btrfs/disk-io.c:1521
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:119
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd3/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 4970 Comm: klogd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:vsnprintf+0x1c4/0xef0 lib/vsprintf.c:2896
Code: 69 06 00 00 e8 1d a7 9c f6 48 8b 44 24 20 42 80 3c 30 00 48 8b 2c 24 74 0a 48 8b 7c 24 18 e8 f3 2a 07 f7 4c 8b 6d 10 49 01 dd <48> 8b 44 24 10 42 0f b6 04 30 84 c0 0f 85 76 0b 00 00 83 c3 08 89
RSP: 0018:ffffc9000158f7e8 EFLAGS: 00000282
RAX: 1ffff920002b1f1e RBX: 0000000000000018 RCX: ffff888037570000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000158f8e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000007 R12: ffffc9000158faca
R13: ffffc9000158f8a8 R14: dffffc0000000000 R15: ffffffff8b4da34b
FS: 00007f74b0cbfc80(0000) GS:ffff888125eec000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556ba7ca48 CR3: 00000000371bc000 CR4: 00000000003526f0
Call Trace:
sprintf+0xe7/0x140 lib/vsprintf.c:3102
print_time kernel/printk/printk.c:1359 [inline]
info_print_prefix+0x16b/0x360 kernel/printk/printk.c:1385
record_print_text+0x176/0x450 kernel/printk/printk.c:1434
syslog_print+0x3b0/0x610 kernel/printk/printk.c:1645
do_syslog+0x583/0x7d0 kernel/printk/printk.c:1763
__do_sys_syslog kernel/printk/printk.c:1855 [inline]
__se_sys_syslog kernel/printk/printk.c:1853 [inline]
__x64_sys_syslog+0x7c/0x90 kernel/printk/printk.c:1853
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0x560 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f74b0e89a37
Code: 73 01 c3 48 8b 0d c1 f3 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 91 f3 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffe116e1b48 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: ffffffffffffffda RBX: 00007f74b1029490 RCX: 00007f74b0e89a37
RDX: 00000000000003ff RSI: 00007f74b1029490 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000004000 R11: 0000000000000206 R12: 00007f74b1029490
R13: 00007f74b1006dfe R14: 00007f74b1029870 R15: 00007f74b1029870