INFO: task syz-executor:5594 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:22216 pid:5594 tgid:5594 ppid:5593 task_flags:0x440100 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__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:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7445
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7636
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7673
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2483
ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7858
do_page_mkwrite+0x147/0x310 mm/memory.c:3878
wp_page_shared mm/memory.c:4279 [inline]
do_wp_page+0x1a85/0x4b60 mm/memory.c:4502
handle_pte_fault mm/memory.c:6672 [inline]
__handle_mm_fault mm/memory.c:6797 [inline]
handle_mm_fault+0x15c1/0x3540 mm/memory.c:6964
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: 0033:0x7fcc5707cae2
RSP: 002b:00007ffe4a558980 EFLAGS: 00010202
RAX: 00007fcc5503c000 RBX: 000055557b6aa290 RCX: 0000000000000003
RDX: 00000000000022fc RSI: 000055557b6ae2b8 RDI: 0000000000000008
RBP: 00007ffe4a558e80 R08: 000055557b6ae2c0 R09: 00000000000000a6
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffe4a558cc0
R13: 00007ffe4a558ab0 R14: 585858582e7a7973 R15: 00007ffe4a558a00
INFO: task syz.1.635:7670 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.1.635 state:D stack:25576 pid:7670 tgid:7670 ppid:5608 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__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:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7445
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7636
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7673
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
file_update_time_flags+0x399/0x440 fs/inode.c:2483
ext4_page_mkwrite+0x21f/0x1470 fs/ext4/inode.c:7858
do_page_mkwrite+0x147/0x310 mm/memory.c:3878
do_shared_fault mm/memory.c:6171 [inline]
do_fault mm/memory.c:6233 [inline]
do_pte_missing+0x70f/0x3570 mm/memory.c:4762
handle_pte_fault mm/memory.c:6648 [inline]
__handle_mm_fault mm/memory.c:6797 [inline]
handle_mm_fault+0x1a2a/0x3540 mm/memory.c:6964
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: 0033:0x7f688c672c09
RSP: 002b:00007ffddfe77570 EFLAGS: 00010202
RAX: 0000001b33224000 RBX: 0000000000000000 RCX: 00000000005ffde8
RDX: 0000001b33223ffc RSI: 00000000005ffde8 RDI: 00007f688d555700
RBP: 0000000000000000 R08: 0000000000000000 R09: 00007f688ca12000
R10: 00007f688d555700 R11: 0000000000000000 R12: 0000000000000000
R13: 000000000000a26e R14: ffffffff816db830 R15: 00007f688d555720
INFO: task syz.4.637:7674 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.4.637 state:D stack:26696 pid:7674 tgid:7674 ppid:5604 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__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:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7445
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7636
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7673
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
touch_atime+0x568/0x670 fs/inode.c:2328
file_accessed include/linux/fs.h:2279 [inline]
ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2916 [inline]
__mmap_region mm/vma.c:3033 [inline]
mmap_region+0xef9/0x2840 mm/vma.c:3131
do_mmap+0xe0a/0x1300 mm/mmap.c:573
vm_mmap_pgoff+0x27a/0x520 mm/util.c:581
ksys_mmap_pgoff+0x4dc/0x760 mm/mmap.c:619
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faaa1b9e2c2
RSP: 002b:00007ffd1de96aa8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b32f64000 RCX: 00007faaa1b9e2c2
RDX: 0000000000000003 RSI: 00000000005c0000 RDI: 0000001b32f64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 000000000000007b
R13: 00000000000927c0 R14: 000000000003f7b5 R15: 00007ffd1de96d80
INFO: task syz.0.639:7675 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.0.639 state:D stack:26808 pid:7675 tgid:7675 ppid:5607 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__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:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7445
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7636
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7673
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
touch_atime+0x568/0x670 fs/inode.c:2328
file_accessed include/linux/fs.h:2279 [inline]
ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2916 [inline]
__mmap_region mm/vma.c:3033 [inline]
mmap_region+0xef9/0x2840 mm/vma.c:3131
do_mmap+0xe0a/0x1300 mm/mmap.c:573
vm_mmap_pgoff+0x27a/0x520 mm/util.c:581
ksys_mmap_pgoff+0x4dc/0x760 mm/mmap.c:619
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faa49f9e2c2
RSP: 002b:00007ffd98a76768 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b32b64000 RCX: 00007faa49f9e2c2
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b32b64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 0000000000000084
R13: 00000000000927c0 R14: 000000000003f7f1 R15: 00007ffd98a76a40
INFO: task syz.2.638:7676 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.2.638 state:D stack:26936 pid:7676 tgid:7676 ppid:5606 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__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:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7445
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7636
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7673
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
touch_atime+0x568/0x670 fs/inode.c:2328
file_accessed include/linux/fs.h:2279 [inline]
ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2916 [inline]
__mmap_region mm/vma.c:3033 [inline]
mmap_region+0xef9/0x2840 mm/vma.c:3131
do_mmap+0xe0a/0x1300 mm/mmap.c:573
vm_mmap_pgoff+0x27a/0x520 mm/util.c:581
ksys_mmap_pgoff+0x4dc/0x760 mm/mmap.c:619
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbd65b9e2c2
RSP: 002b:00007fff2e48e508 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b32d64000 RCX: 00007fbd65b9e2c2
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b32d64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 0000000000000068
R13: 00000000000927c0 R14: 000000000003f827 R15: 00007fff2e48e7e0
INFO: task syz.3.640:7677 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.3.640 state:D stack:26936 pid:7677 tgid:7677 ppid:5605 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5584 [inline]
__schedule+0x1b47/0x5b40 kernel/sched/core.c:7387
__schedule_loop kernel/sched/core.c:7464 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7479
io_schedule+0x7f/0xd0 kernel/sched/core.c:8151
bit_wait_io+0x13/0x110 kernel/sched/wait_bit.c:258
__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:106 [inline]
do_get_write_access+0x658/0x10c0 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d7/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0xec/0x620 fs/ext4/ext4_jbd2.c:253
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:7445
__ext4_mark_inode_dirty+0x141/0x7e0 fs/ext4/inode.c:7636
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:7673
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2741
generic_update_time fs/inode.c:2253 [inline]
touch_atime+0x568/0x670 fs/inode.c:2328
file_accessed include/linux/fs.h:2279 [inline]
ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2916 [inline]
__mmap_region mm/vma.c:3033 [inline]
mmap_region+0xef9/0x2840 mm/vma.c:3131
do_mmap+0xe0a/0x1300 mm/mmap.c:573
vm_mmap_pgoff+0x27a/0x520 mm/util.c:581
ksys_mmap_pgoff+0x4dc/0x760 mm/mmap.c:619
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f735f79e2c2
RSP: 002b:00007fffef4059f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b32e64000 RCX: 00007f735f79e2c2
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b32e64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 00000000000000a3
R13: 00000000000927c0 R14: 000000000003f7e3 R15: 00007fffef405cd0
Showing all locks held in the system:
locks held by pr/ttyS0/34: 2, last CPU#0:
#0: ffffffff8fc341f8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline]
#0: ffffffff8fc341f8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:493 [inline]
#0: ffffffff8fc341f8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291
#1: ffffffff9bd916b8 (&port_lock_key){-.-.}-{3:3}, at: __uart_port_lock_irqsave include/linux/serial_core.h:613 [inline]
#1: ffffffff9bd916b8 (&port_lock_key){-.-.}-{3:3}, at: univ8250_console_device_lock+0x67/0xc0 drivers/tty/serial/8250/8250_core.c:413
locks held by khungtaskd/35: 1, last CPU#1:
#0: ffffffff8fd5a6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffffffff8fd5a6e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8fd5a6e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871
locks held by kworker/u8:3/51: 3, last CPU#1:
#0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff88801c0ac148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90000bb7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90000bb7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90000bb7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90000bb7c40 ((work_completion)(&rdev->wiphy_work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff888066d30800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: class_wiphy_constructor include/net/cfg80211.h:6990 [inline]
#2: ffff888066d30800 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: cfg80211_wiphy_work+0xb4/0x420 net/wireless/core.c:596
locks held by klogd/4963: 1, last CPU#1:
#0: ffffffff8feb12f0 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:213 [inline]
#0: ffffffff8feb12f0 (remove_cache_srcu){.+.+}-{0:0}, at: srcu_read_lock+0x27/0x60 include/linux/srcu.h:320
locks held by getty/5362: 2, on CPU#1:
#0: ffff88803380c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000322e2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45a/0x1360 drivers/tty/n_tty.c:2211
locks held by syz-executor/5594: 3, on CPU#0:
#0: ffff888073f20948 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:337
#1: ffff88807fcbc558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff88807fcbc558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7857
#2: ffff88807fcba950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by kworker/u8:12/5891: 4, on CPU#1:
#0: ffff888021afc148 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#0: ffff888021afc148 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffff888021afc148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#0: ffff888021afc148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#1: ffffc90004f9fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline]
#1: ffffc90004f9fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#1: ffffc90004f9fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3460 [inline]
#1: ffffc90004f9fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3578
#2: ffff88807fcbc0e8 (&type->s_umount_key#35){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:670
#3: ffff88807fc94cd8 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x1f1/0x4e0 fs/ext4/inode.c:3170
locks held by syz.1.635/7670: 3, on CPU#1:
#0: ffff888074fca308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:337
#1: ffff88807fcbc558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff88807fcbc558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1fe/0x1470 fs/ext4/inode.c:7857
#2: ffff88807fcba950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.4.637/7674: 3, on CPU#1:
#0: ffff88807e03e540 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:550 [inline]
#0: ffff88807e03e540 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1ed/0x520 mm/util.c:579
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2279 [inline]
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
#2: ffff88807fcba950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.0.639/7675: 3, on CPU#1:
#0: ffff888079d0d900 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:550 [inline]
#0: ffff888079d0d900 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1ed/0x520 mm/util.c:579
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2279 [inline]
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
#2: ffff88807fcba950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.2.638/7676: 3, on CPU#1:
#0: ffff888078324cc0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:550 [inline]
#0: ffff888078324cc0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1ed/0x520 mm/util.c:579
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2279 [inline]
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
#2: ffff88807fcba950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
locks held by syz.3.640/7677: 3, on CPU#1:
#0: ffff888078323440 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:550 [inline]
#0: ffff888078323440 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1ed/0x520 mm/util.c:579
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2279 [inline]
#1: ffff88807fcbc460 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x277/0x450 fs/ext4/file.c:919
#2: ffff88807fcba950 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fb0/0x21f0 fs/jbd2/transaction.c:444
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 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+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: 34 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:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:425
Code: e8 8e aa 46 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 ef dd bc fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 8a 00 78 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000aa78b8 EFLAGS: 00000002
RAX: 1ffffffff37b2200 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000020
RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff858249d0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff9bd916e0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888123a7d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055885af51660 CR3: 000000000fb48000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:134 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:156 [inline]
wait_for_lsr+0x184/0x2f0 drivers/tty/serial/8250/8250_port.c:2036
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3294 [inline]
__serial8250_console_fifo_write+0xcd/0x3e0 drivers/tty/serial/8250/8250_port.c:3369
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3402 [inline]
__serial8250_console_write drivers/tty/serial/8250/8250_port.c:3456 [inline]
serial8250_console_write+0xa7e/0x1200 drivers/tty/serial/8250/8250_port.c:3520
nbcon_emit_next_record+0xef5/0x1a90 kernel/printk/nbcon.c:-1
nbcon_emit_one kernel/printk/nbcon.c:1157 [inline]
nbcon_kthread_func+0x6d9/0x8d0 kernel/printk/nbcon.c:1271
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