INFO: task kworker/u8:0:12 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0 state:D stack:21544 pid:12 tgid:12 ppid:2 task_flags:0x4248160 flags:0x00080000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
__schedule_loop kernel/sched/core.c:7309 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7324
io_schedule+0x7f/0xd0 kernel/sched/core.c:8152
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:3032 [inline]
blk_mq_submit_bio+0x1522/0x2a40 block/blk-mq.c:3170
__submit_bio_noacct_mq block/blk-core.c:756 [inline]
submit_bio_noacct_nocheck+0x2f4/0xa40 block/blk-core.c:790
blk_crypto_submit_bio include/linux/blk-crypto.h:212 [inline]
ext4_io_submit fs/ext4/page-io.c:396 [inline]
io_submit_add_bh fs/ext4/page-io.c:452 [inline]
ext4_bio_write_folio+0xf90/0x1780 fs/ext4/page-io.c:547
mpage_process_page_bufs+0x6bd/0x8a0 fs/ext4/inode.c:2201
mpage_prepare_extent_to_map+0xf92/0x1890 fs/ext4/inode.c:2743
ext4_do_writepages+0xb8a/0x4770 fs/ext4/inode.c:2884
ext4_writepages+0x241/0x3b0 fs/ext4/inode.c:3032
do_writepages+0x338/0x560 mm/page-writeback.c:2560
__writeback_single_inode+0x136/0x1220 fs/fs-writeback.c:1788
writeback_sb_inodes+0x9de/0x1b00 fs/fs-writeback.c:2099
__writeback_inodes_wb+0x114/0x240 fs/fs-writeback.c:2175
wb_writeback+0x42f/0xad0 fs/fs-writeback.c:2286
wb_check_old_data_flush fs/fs-writeback.c:2390 [inline]
wb_do_writeback fs/fs-writeback.c:2469 [inline]
wb_workfn+0xc92/0x10f0 fs/fs-writeback.c:2497
process_one_work kernel/workqueue.c:3375 [inline]
process_scheduled_works+0xc4e/0x1630 kernel/workqueue.c:3458
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3539
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 jbd2/sda1-8:4944 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8 state:D stack:25176 pid:4944 tgid:4944 ppid:2 task_flags:0x240040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
__schedule_loop kernel/sched/core.c:7309 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7324
io_schedule+0x7f/0xd0 kernel/sched/core.c:8152
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_buffer include/linux/buffer_head.h:418 [inline]
jbd2_journal_commit_transaction+0x2f1d/0x5b70 fs/jbd2/commit.c:834
kjournald2+0x3bc/0x750 fs/jbd2/journal.c:200
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-executor:5602 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:22672 pid:5602 tgid:5602 ppid:5601 task_flags:0x440100 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
__schedule_loop kernel/sched/core.c:7309 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7324
io_schedule+0x7f/0xd0 kernel/sched/core.c:8152
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:105 [inline]
do_get_write_access+0x662/0x1070 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6509
__ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6694
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6731
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729
generic_update_time fs/inode.c:2254 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2484
ext4_page_mkwrite+0x224/0x1140 fs/ext4/inode.c:6897
do_page_mkwrite+0x147/0x310 mm/memory.c:3816
wp_page_shared mm/memory.c:4217 [inline]
do_wp_page+0x1a9c/0x4b80 mm/memory.c:4440
handle_pte_fault mm/memory.c:6583 [inline]
__handle_mm_fault mm/memory.c:6708 [inline]
handle_mm_fault+0x15d7/0x3750 mm/memory.c:6877
do_user_addr_fault+0xa4d/0x1340 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: 0033:0x7f58dac70163
RSP: 002b:00007ffc2d5588c0 EFLAGS: 00010216
RAX: 00007f58d49fdd64 RBX: 00007ffc2d5589f0 RCX: 0000000000000000
RDX: 00007f58d49fdd60 RSI: 0000000000000008 RDI: 00007ffc2d5589f0
RBP: 00000000000003e6 R08: 0000000000000000 R09: 0000000000000000
R10: 00007ffc2d5589d0 R11: 0000000000000000 R12: 0000000000000000
R13: 000000000000229c R14: ffffffffffffdd64 R15: 0000000000000000
INFO: task syz.2.3177:13883 blocked in I/O wait for more than 143 seconds.
Tainted: G L syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.3177 state:D stack:25608 pid:13883 tgid:13883 ppid:5612 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x1b2a/0x59a0 kernel/sched/core.c:7232
__schedule_loop kernel/sched/core.c:7309 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7324
io_schedule+0x7f/0xd0 kernel/sched/core.c:8152
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x300 kernel/sched/wait_bit.c:52
out_of_line_wait_on_bit+0x13b/0x190 kernel/sched/wait_bit.c:67
wait_on_bit_io include/linux/wait_bit.h:105 [inline]
do_get_write_access+0x662/0x1070 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xf1/0x620 fs/ext4/ext4_jbd2.c:249
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6509
__ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6694
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6731
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729
generic_update_time fs/inode.c:2254 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2484
ext4_page_mkwrite+0x224/0x1140 fs/ext4/inode.c:6897
do_page_mkwrite+0x147/0x310 mm/memory.c:3816
do_shared_fault mm/memory.c:6077 [inline]
do_fault mm/memory.c:6139 [inline]
do_pte_missing+0x757/0x34b0 mm/memory.c:4700
handle_pte_fault mm/memory.c:6559 [inline]
__handle_mm_fault mm/memory.c:6708 [inline]
handle_mm_fault+0x1a53/0x3750 mm/memory.c:6877
do_user_addr_fault+0xa4d/0x1340 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: 0033:0x7fafe1872eb2
RSP: 002b:00007ffe7828adf0 EFLAGS: 00010202
RAX: 0000000000001008 RBX: 00007fafe2755720 RCX: 0000000000000000
RDX: 0000001b33b23000 RSI: 0000000000000008 RDI: 00007fafe2755720
RBP: 0000000000000062 R08: 00007fafe1c10000 R09: 00007fafe1c26038
R10: 0000000000000003 R11: 0000000000000002 R12: ffffffff849467df
R13: 00007fafe1c26038 R14: 0000000000000041 R15: fffffffffffff000
Showing all locks held in the system:
locks held by kworker/u8:0/12: 4, on CPU#0:
#0: ffff888020e9f940 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888020e9f940 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888020e9f940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff888020e9f940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc90000117c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#2: ffff88807f8c20e8 (&type->s_umount_key#34){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:688
#3: ffff88807f8c0c98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline]
#3: ffff88807f8c0c98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1887 [inline]
#3: ffff88807f8c0c98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3031
locks held by kworker/u8:1/13: 3, last CPU#0:
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc90000127c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#2: ffff88802b22c258 (&devlink->lock_key#7){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40 drivers/net/netdevsim/dev.c:909
locks held by pr/ttyS0/16: 2, last CPU#1:
#0: ffffffff8ea36278 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
#0: ffffffff8ea36278 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline]
#0: ffffffff8ea36278 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291
#1: ffffffff9aafec18 (&port_lock_key){-.-.}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline]
#1: ffffffff9aafec18 (&port_lock_key){-.-.}-{3:3}, at: univ8250_console_device_lock+0x67/0xc0 drivers/tty/serial/8250/8250_core.c:413
locks held by khungtaskd/33: 1, last CPU#0:
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb5c6a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6837
locks held by kworker/u8:5/149: 5, last CPU#0:
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc90002ec7c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90002ec7c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90002ec7c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc90002ec7c40 ((work_completion)(&(&kfence_timer)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#2: ffffffff8e9e9770 (cpu_hotplug_lock){++++}-{0:0}, at: static_key_enable+0x12/0x20 kernel/jump_label.c:222
#3: ffffffff8ec31380 (jump_label_mutex){+.+.}-{4:4}, at: jump_label_lock kernel/jump_label.c:27 [inline]
#3: ffffffff8ec31380 (jump_label_mutex){+.+.}-{4:4}, at: static_key_enable_cpuslocked+0xcb/0x240 kernel/jump_label.c:207
#4: ffffffff8e9ff4a0 (text_mutex){+.+.}-{4:4}, at: arch_jump_label_transform_apply+0x17/0x30 arch/x86/kernel/jump_label.c:145
locks held by kworker/u8:6/768: 3, last CPU#0:
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff88801b06c140 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc90004337c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90004337c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90004337c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc90004337c40 ((work_completion)(&(&nsim_dev->trap_data->trap_report_dw)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#2: ffff88807723a258 (&devlink->lock_key#5){+.+.}-{4:4}, at: nsim_dev_trap_report_work+0x57/0xb40 drivers/net/netdevsim/dev.c:909
locks held by kworker/u8:9/3310: 2, last CPU#0:
#0: ffff888031e1c140 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888031e1c140 ((wq_completion)bat_events){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888031e1c140 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#0: ffff888031e1c140 ((wq_completion)bat_events){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
#1: ffffc9000e077c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc9000e077c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc9000e077c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3340 [inline]
#1: ffffc9000e077c40 ((work_completion)(&(&bat_priv->dat.work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97e/0x1630 kernel/workqueue.c:3458
locks held by getty/5369: 2, on CPU#0:
#0: ffff8880355390a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000321e2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/5602: 3, on CPU#0:
#0: ffff8880263976c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x202/0x1140 fs/ext4/inode.c:6896
#2: ffff88807f8f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444
locks held by syz-executor/13468: 3, on CPU#1:
#0: ffff88807f8c2460 (sb_writers#4){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:494
#1: ffff888056dbd510 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1070 [inline]
#1: ffff888056dbd510 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2918 [inline]
#1: ffff888056dbd510 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2942 [inline]
#1: ffff888056dbd510 (&type->i_mutex_dir_key#3/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:5092
#2: ffff88807f8f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444
locks held by syz.2.3177/13883: 3, on CPU#1:
#0: ffff888078376d08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff88807f8c2558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x202/0x1140 fs/ext4/inode.c:6896
#2: ffff88807f8f6938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
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+0x17a/0x380 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:353 [inline]
watchdog+0xfd7/0x1030 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:delay_tsc+0x5b/0xc0 arch/x86/lib/delay.c:79
Code: 90 49 89 d7 49 c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 53 bf 01 00 00 00 e8 c2 e6 ba f5 65 8b 05 cb 6a 97 07 85 c0 74 1c f3 90 01 00 00 00 e8 0b e5 ba f5 e8 36 7c 01 00 39 c5 75 0e 0f 01 f9
RSP: 0018:ffffc900001578b8 EFLAGS: 00000082
RAX: 0000000080000001 RBX: 0000000000000899 RCX: 0000000000000000
RDX: 0000000000000150 RSI: ffffffff8c4c7660 RDI: 00000000ffffffff
RBP: 0000000000000001 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff8bd9d510 R12: 1ffffffff355fddd
R13: 00000000ffffffff R14: 000001506fe9b726 R15: 00000000000006fd
FS: 0000000000000000(0000) GS:ffff88812500c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ed318bb168 CR3: 000000000e948000 CR4: 00000000003526f0
Call Trace:
udelay include/asm-generic/delay.h:62 [inline]
wait_for_lsr+0x147/0x2f0 drivers/tty/serial/8250/8250_port.c:2019
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline]
__serial8250_console_fifo_write+0xcd/0x3e0 drivers/tty/serial/8250/8250_port.c:3345
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3429 [inline]
serial8250_console_write+0xaa1/0x1200 drivers/tty/serial/8250/8250_port.c:3493
nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
nbcon_emit_one kernel/printk/nbcon.c:1157 [inline]
nbcon_kthread_func+0x679/0x880 kernel/printk/nbcon.c:1271
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