INFO: task syz.2.3:6079 blocked for more than 145 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.3 state:D stack:21040 pid:6079 tgid:6048 ppid:5859 task_flags:0x440140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
__bch2_two_state_lock+0x1ea/0x370 fs/bcachefs/two_state_shared_lock.c:7
bch2_two_state_lock fs/bcachefs/two_state_shared_lock.h:55 [inline]
bch2_readahead+0x94f/0x1100 fs/bcachefs/fs-io-buffered.c:296
read_pages+0x17a/0x580 mm/readahead.c:160
page_cache_ra_order+0x8ca/0xd40 mm/readahead.c:512
filemap_readahead mm/filemap.c:2572 [inline]
filemap_get_pages+0xb22/0x1ea0 mm/filemap.c:2617
filemap_splice_read+0x581/0xc60 mm/filemap.c:2991
do_splice_read fs/splice.c:982 [inline]
splice_direct_to_actor+0x4a9/0xcc0 fs/splice.c:1086
do_splice_direct_actor fs/splice.c:1204 [inline]
do_splice_direct+0x181/0x270 fs/splice.c:1230
do_sendfile+0x4da/0x7e0 fs/read_write.c:1370
__do_sys_sendfile64 fs/read_write.c:1431 [inline]
__se_sys_sendfile64+0x13e/0x190 fs/read_write.c:1417
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f538618ebe9
RSP: 002b:00007f53843d5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007f53863b6090 RCX: 00007f538618ebe9
RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000006
RBP: 00007f5386211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000800000009 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f53863b6128 R14: 00007f53863b6090 R15: 00007ffeca7b5f88
INFO: task syz.2.3:6082 blocked for more than 147 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.3 state:D stack:25952 pid:6082 tgid:6048 ppid:5859 task_flags:0x400140 flags:0x00004006
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
io_schedule+0x80/0xd0 kernel/sched/core.c:7903
folio_wait_bit_common+0x6b0/0xb90 mm/filemap.c:1317
folio_lock include/linux/pagemap.h:1133 [inline]
truncate_inode_pages_range+0xa77/0xda0 mm/truncate.c:433
truncate_inode_pages mm/truncate.c:460 [inline]
truncate_pagecache mm/truncate.c:769 [inline]
truncate_setsize+0xcf/0xf0 mm/truncate.c:794
bchfs_truncate+0x622/0xc20 fs/bcachefs/fs-io.c:488
notify_change+0xb36/0xe40 fs/attr.c:552
do_truncate+0x1a4/0x220 fs/open.c:68
handle_truncate fs/namei.c:3508 [inline]
do_open fs/namei.c:3891 [inline]
path_openat+0x306c/0x3830 fs/namei.c:4046
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1435
do_sys_open fs/open.c:1450 [inline]
__do_sys_open fs/open.c:1458 [inline]
__se_sys_open fs/open.c:1454 [inline]
__x64_sys_open+0x11e/0x150 fs/open.c:1454
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f538618ebe9
RSP: 002b:00007f5383f91038 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: ffffffffffffffda RBX: 00007f53863b6270 RCX: 00007f538618ebe9
RDX: 0000000000000000 RSI: 000000000014927e RDI: 0000200000000180
RBP: 00007f5386211e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f53863b6308 R14: 00007f53863b6270 R15: 00007ffeca7b5f88
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5867 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: usb_hub_wq hub_event
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 2e 8f 70 fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 5f f8 d3 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 d5 24 c1 fb cc 44 89 f9 80 e1 07
RSP: 0018:ffffc9000414ee50 EFLAGS: 00000002
RAX: 1ffffffff33bde00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000031935 RDI: 0000000000031936
RBP: ffffffff99def670 R08: ffff8880241e0237 R09: 1ffff1100483c046
R10: dffffc0000000000 R11: ffffffff854f1bb0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff99def3e0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125d1b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055be10ed9660 CR3: 0000000075284000 CR4: 0000000000350ef0
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+0x1a1/0x2f0 drivers/tty/serial/8250/8250_port.c:1984
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3288 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3311 [inline]
serial8250_console_write+0x134c/0x1ba0 drivers/tty/serial/8250/8250_port.c:3396
console_emit_next_record kernel/printk/printk.c:3138 [inline]
console_flush_all+0x728/0xc40 kernel/printk/printk.c:3226
__console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
console_unlock+0xc4/0x270 kernel/printk/printk.c:3325
vprintk_emit+0x5b7/0x7a0 kernel/printk/printk.c:2450
dev_vprintk_emit+0x337/0x3f0 drivers/base/core.c:4914
dev_printk_emit+0xe0/0x130 drivers/base/core.c:4925
_dev_info+0x10a/0x160 drivers/base/core.c:4983
usb_disconnect+0xdd/0x950 drivers/usb/core/hub.c:2326
hub_port_connect drivers/usb/core/hub.c:5406 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
port_event drivers/usb/core/hub.c:5870 [inline]
hub_event+0x1cf5/0x4a20 drivers/usb/core/hub.c:5952
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245