INFO: task jbd2/sda1-8:4916 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 messag[ 502.118784][ T37] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:jbd2/sda1-8 state:D stack:24752 pid:4916 tgid:4916 ppid:2 task_flags:0x240040 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x2f0 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:422 [inline]
jbd2_journal_commit_transaction+0x2f26/0x5ba0 fs/jbd2/commit.c:834
kjournald2+0x3bc/0x750 fs/jbd2/journal.c:199
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:5574 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:22344 pid:5574 tgid:5574 ppid:5573 task_flags:0x440100 flags:0x00080000
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x2f0 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+0x670/0x1090 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427
__ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709
generic_update_time fs/inode.c:2257 [inline]
file_update_time_flags+0x3f4/0x4b0 fs/inode.c:2487
ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6805
do_page_mkwrite+0x14a/0x310 mm/memory.c:3684
wp_page_shared mm/memory.c:4085 [inline]
do_wp_page+0x1f32/0x3d90 mm/memory.c:4304
handle_pte_fault mm/memory.c:6395 [inline]
__handle_mm_fault mm/memory.c:6517 [inline]
handle_mm_fault+0xa03/0x13f0 mm/memory.c:6686
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: 0033:0x7ffbe67dc662
RSP: 002b:00007ffd23d93c30 EFLAGS: 00010202
RAX: 00007ffbe486c000 RBX: 0000555586734510 RCX: 0000000000000001
RDX: 0000000000000ffb RSI: 0000555586736ff0 RDI: 0000000000000002
RBP: 00007ffd23d94130 R08: 0000555586737020 R09: 0000000000000099
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd23d93f70
R13: 00007ffd23d93d60 R14: 585858582e7a7973 R15: 00007ffd23d93cb0
INFO: task syz.3.981:8415 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.3.981 state:D stack:25576 pid:8415 tgid:8415 ppid:5594 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x2f0 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+0x670/0x1090 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427
__ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709
generic_update_time fs/inode.c:2257 [inline]
file_update_time_flags+0x3f4/0x4b0 fs/inode.c:2487
ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6805
do_page_mkwrite+0x14a/0x310 mm/memory.c:3684
do_shared_fault mm/memory.c:5936 [inline]
do_fault mm/memory.c:5998 [inline]
do_pte_missing+0x734/0x28f0 mm/memory.c:4566
handle_pte_fault mm/memory.c:6379 [inline]
__handle_mm_fault mm/memory.c:6517 [inline]
handle_mm_fault+0xd28/0x13f0 mm/memory.c:6686
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: 0033:0x7f8d6a002729
RSP: 002b:00007ffcc8a3bda0 EFLAGS: 00010202
RAX: 0000001b32123000 RBX: ffffffff84bcce3b RCX: 0000001b32122ff8
RDX: 0000001b31d24220 RSI: 0000000000000008 RDI: 00007f8d6aee5720
RBP: 00000000000001d7 R08: 00007f8d6a3a0000 R09: 00007f8d6a3a2000
R10: 0000000084bcce3f R11: 0000000000000013 R12: 00007f8d6a3b6038
R13: 000000000000053c R14: ffffffff84bccec6 R15: 00007f8d6aee5720
INFO: task syz.1.988:8435 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.1.988 state:D stack:27096 pid:8435 tgid:8435 ppid:5593 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x2f0 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+0x670/0x1090 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427
__ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709
generic_update_time fs/inode.c:2257 [inline]
touch_atime+0x565/0x670 fs/inode.c:2332
file_accessed include/linux/fs.h:2272 [inline]
ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2672 [inline]
__mmap_region mm/vma.c:2758 [inline]
mmap_region+0xe78/0x2310 mm/vma.c:2860
do_mmap+0xc1e/0x10b0 mm/mmap.c:560
vm_mmap_pgoff+0x275/0x4e0 mm/util.c:581
ksys_mmap_pgoff+0x4a6/0x720 mm/mmap.c:606
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6cf3a1de42
RSP: 002b:00007fff1e08fbd8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b31b64000 RCX: 00007f6cf3a1de42
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b31b64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 00000000000001e5
R13: 00000000000927c0 R14: 0000000000055858 R15: 00007fff1e08feb0
INFO: task syz.2.989:8436 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.2.989 state:D stack:27088 pid:8436 tgid:8436 ppid:5590 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x2f0 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+0x670/0x1090 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427
__ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709
generic_update_time fs/inode.c:2257 [inline]
touch_atime+0x565/0x670 fs/inode.c:2332
file_accessed include/linux/fs.h:2272 [inline]
ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2672 [inline]
__mmap_region mm/vma.c:2758 [inline]
mmap_region+0xe78/0x2310 mm/vma.c:2860
do_mmap+0xc1e/0x10b0 mm/mmap.c:560
vm_mmap_pgoff+0x275/0x4e0 mm/util.c:581
ksys_mmap_pgoff+0x4a6/0x720 mm/mmap.c:606
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f09ed1bde42
RSP: 002b:00007ffd069ae358 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b31c64000 RCX: 00007f09ed1bde42
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b31c64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 0000000000000080
R13: 00000000000927c0 R14: 0000000000055848 R15: 00007ffd069ae630
INFO: task syz.0.990:8439 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.0.990 state:D stack:27256 pid:8439 tgid:8439 ppid:5591 task_flags:0x440040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5510 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7234
__schedule_loop kernel/sched/core.c:7311 [inline]
schedule+0x164/0x2b0 kernel/sched/core.c:7326
io_schedule+0x80/0xe0 kernel/sched/core.c:8154
bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:250
__wait_on_bit+0xac/0x2f0 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+0x670/0x1090 fs/jbd2/transaction.c:1113
jbd2_journal_get_write_access+0x1d6/0x230 fs/jbd2/transaction.c:1263
__ext4_journal_get_write_access+0x1c3/0x590 fs/ext4/ext4_jbd2.c:241
ext4_reserve_inode_write+0x294/0x360 fs/ext4/inode.c:6427
__ext4_mark_inode_dirty+0x13e/0x700 fs/ext4/inode.c:6602
ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6639
__mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2709
generic_update_time fs/inode.c:2257 [inline]
touch_atime+0x565/0x670 fs/inode.c:2332
file_accessed include/linux/fs.h:2272 [inline]
ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
vfs_mmap_prepare include/linux/fs.h:2071 [inline]
call_mmap_prepare mm/vma.c:2672 [inline]
__mmap_region mm/vma.c:2758 [inline]
mmap_region+0xe78/0x2310 mm/vma.c:2860
do_mmap+0xc1e/0x10b0 mm/mmap.c:560
vm_mmap_pgoff+0x275/0x4e0 mm/util.c:581
ksys_mmap_pgoff+0x4a6/0x720 mm/mmap.c:606
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7535f7de42
RSP: 002b:00007ffff8adad18 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b31a64000 RCX: 00007f7535f7de42
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b31a64000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 000000000000008c
R13: 00000000000927c0 R14: 0000000000055c25 R15: 00007ffff8adaff0
Showing all locks held in the system:
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/37:
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
#0: ffffffff8e1c3000 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by klogd/4943:
2 locks held by getty/5340:
#0: ffff888035f4c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003cc62e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/5574:
#0: ffff88804164d588 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6804
#2: ffff88803648abb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444
3 locks held by syz.3.981/8415:
#0: ffff88803f6f7e48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline]
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline]
#1: ffff88803647e678 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6804
#2: ffff88803648abb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444
3 locks held by syz.1.988/8435:
#0: ffff88802aedacb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#0: ffff88802aedacb0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1e0/0x4e0 mm/util.c:579
#1: ffff88803647e500 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2272 [inline]
#1: ffff88803647e500 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
#2: ffff88803648abb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444
3 locks held by syz.2.989/8436:
#0: ffff8880400791b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#0: ffff8880400791b0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1e0/0x4e0 mm/util.c:579
#1: ffff88803647e500 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2272 [inline]
#1: ffff88803647e500 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
#2: ffff88803648abb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444
3 locks held by syz.0.990/8439:
#0: ffff88803e9a47b0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
#0: ffff88803e9a47b0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1e0/0x4e0 mm/util.c:579
#1: ffff88803647e500 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2272 [inline]
#1: ffff88803647e500 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:840
#2: ffff88803648abb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fc3/0x2210 fs/jbd2/transaction.c:444
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT_{RT,(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:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
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+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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17 Comm: pr/legacy Tainted: G L syzkaller #0 PREEMPT_{RT,(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:401
Code: e8 ee 1f 70 fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 4f 96 d9 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90000167a28 EFLAGS: 00000202
RAX: 1ffffffff33c8c00 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8555a7f0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff99e46340 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888125c46000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0b937d1700 CR3: 000000000dfb0000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x190/0x300 drivers/tty/serial/8250/8250_port.c:1982
serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3235 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3300 [inline]
serial8250_console_write+0x113a/0x1b40 drivers/tty/serial/8250/8250_port.c:3385
console_emit_next_record kernel/printk/printk.c:3163 [inline]
console_flush_one_record+0x642/0xb50 kernel/printk/printk.c:3269
legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3712
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