INFO: task kworker/u8:2:33 blocked in I/O wait 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:21104 pid:33 tgid:33 ppid:2 task_flags:0x4248060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
io_schedule+0x7f/0xd0 kernel/sched/core.c:8146
rq_qos_wait+0x266/0x360 block/blk-rq-qos.c:307
__wbt_wait block/blk-wbt.c:598 [inline]
wbt_wait+0x326/0x550 block/blk-wbt.c:658
__rq_qos_throttle+0x6b/0xb0 block/blk-rq-qos.c:66
rq_qos_throttle block/blk-rq-qos.h:164 [inline]
blk_mq_get_new_requests block/blk-mq.c:3046 [inline]
blk_mq_submit_bio+0x1697/0x2c40 block/blk-mq.c:3188
__submit_bio_noacct_mq block/blk-core.c:757 [inline]
submit_bio_noacct_nocheck+0x358/0xb10 block/blk-core.c:791
blk_crypto_submit_bio include/linux/blk-crypto.h:212 [inline]
ext4_io_submit fs/ext4/page-io.c:399 [inline]
io_submit_add_bh fs/ext4/page-io.c:455 [inline]
ext4_bio_write_folio+0x101a/0x18c0 fs/ext4/page-io.c:550
mpage_map_and_submit_buffers fs/ext4/inode.c:2457 [inline]
mpage_map_and_submit_extent fs/ext4/inode.c:2647 [inline]
ext4_do_writepages+0x22f6/0x44a0 fs/ext4/inode.c:3077
ext4_writepages+0x1fe/0x4e0 fs/ext4/inode.c:3171
do_writepages+0x338/0x560 mm/page-writeback.c:2562
__writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1809
writeback_sb_inodes+0x9de/0x1af0 fs/fs-writeback.c:2120
__writeback_inodes_wb+0x114/0x250 fs/fs-writeback.c:2196
wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2307
wb_check_old_data_flush fs/fs-writeback.c:2411 [inline]
wb_do_writeback fs/fs-writeback.c:2490 [inline]
wb_workfn+0xc92/0x10f0 fs/fs-writeback.c:2518
process_one_work kernel/workqueue.c:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
kthread+0x38b/0x480 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 jbd2/sda1-8:4969 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8 state:D stack:26280 pid:4969 tgid:4969 ppid:2 task_flags:0x240040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
jbd2_journal_wait_updates+0x19a/0x280 fs/jbd2/transaction.c:844
jbd2_journal_commit_transaction+0x93f/0x5c80 fs/jbd2/commit.c:482
kjournald2+0x3bc/0x740 fs/jbd2/journal.c:200
kthread+0x38b/0x480 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.0.215:6224 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.215 state:D stack:27880 pid:6224 tgid:6224 ppid:5860 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5583 [inline]
__schedule+0x17dd/0x5830 kernel/sched/core.c:7382
__schedule_loop kernel/sched/core.c:7459 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7474
wait_transaction_locked+0x1d6/0x280 fs/jbd2/transaction.c:152
add_transaction_credits fs/jbd2/transaction.c:-1 [inline]
start_this_handle+0x7e6/0x21f0 fs/jbd2/transaction.c:403
jbd2__journal_start+0x2c0/0x5d0 fs/jbd2/transaction.c:502
__ext4_journal_start_sb+0x205/0x780 fs/ext4/ext4_jbd2.c:126
__ext4_journal_start fs/ext4/ext4_jbd2.h:238 [inline]
ext4_dirty_inode+0x93/0x110 fs/ext4/inode.c:7676
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2750
generic_update_time fs/inode.c:2264 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2494
ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7864
do_page_mkwrite+0x147/0x310 mm/memory.c:3884
do_shared_fault mm/memory.c:6180 [inline]
do_fault mm/memory.c:6242 [inline]
do_pte_missing+0x70f/0x3570 mm/memory.c:4771
handle_pte_fault mm/memory.c:6657 [inline]
__handle_mm_fault mm/memory.c:6809 [inline]
handle_mm_fault+0x1807/0x2f80 mm/memory.c:6976
do_user_addr_fault+0xb35/0x1480 arch/x86/mm/fault.c:1343
handle_page_fault arch/x86/mm/fault.c:1483 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1536
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:595
RIP: 0033:0x7fdb8486cea3
RSP: 002b:00007ffcc2283eb0 EFLAGS: 00010246
RAX: 000000000003fde8 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000001b32f24000 RSI: 0000000000040000 RDI: 00007fdb84be7708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffcc2284140
Showing all locks held in the system:
locks held by kworker/u8:2/33: 5, on CPU#0:
#0: ffff888021efb948 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888021efb948 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888021efb948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff888021efb948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90000a97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90000a97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90000a97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90000a97c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff888038068100 (&type->s_umount_key#34){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:642
#3: ffff888038058cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1f1/0x4e0 fs/ext4/inode.c:3170
#4: ffff888038076950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by khungtaskd/37: 1, last CPU#1:
#0: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff9015a420 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by getty/5397: 2, on CPU#0:
#0: ffff8880342820a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000324b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz.0.215/6224: 2, on CPU#1:
#0: ffff88805aa6de48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:339
#1: ffff888038068570 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff888038068570 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7863
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:123
nmi_trigger_cpumask_backtrace+0x17d/0x390 lib/nmi_backtrace.c:66
trigger_all_cpu_backtrace include/linux/nmi.h:164 [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:377 [inline]
watchdog+0x1073/0x10f0 kernel/hung_task.c:598
kthread+0x38b/0x480 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: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64
Code: 5b 93 02 c3 cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 03 9b 10 00 fb f4 3c 17 03 00 cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90
RSP: 0018:ffffffff8fe07ca0 EFLAGS: 00000242
RAX: 000000000010d401 RBX: ffffffff819cd3e0 RCX: 8000000000000001
RDX: 0000000000000001 RSI: ffffffff8e7e9d49 RDI: ffffffff8c8ff980
RBP: ffffffff8fe07d78 R08: ffff8880b8233d9b R09: 1ffff110170467b3
R10: dffffc0000000000 R11: ffffed10170467b4 R12: 0000000000000000
R13: 1ffffffff1fd1df8 R14: 1ffffffff1fc0f9c R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff888123376000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f24455f2630 CR3: 000000000ff48000 CR4: 00000000003526f0
Call Trace:
arch_safe_halt arch/x86/kernel/process.c:767 [inline]
default_idle+0x9/0x20 arch/x86/kernel/process.c:768
default_idle_call+0x72/0xb0 kernel/sched/idle.c:122
cpuidle_idle_call kernel/sched/idle.c:199 [inline]
do_idle+0x2e0/0x540 kernel/sched/idle.c:355
cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:458
rest_init+0x378/0x3a0 init/main.c:789
start_kernel+0x392/0x3e0 init/main.c:1247
x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
x86_64_start_kernel+0x137/0x1b0 arch/x86/kernel/head64.c:291
common_startup_64+0x13e/0x157