INFO: task syz-executor:4260 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:21904 pid:4260  ppid:4259   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 wp_page_shared+0x167/0x370 mm/memory.c:3358
 handle_pte_fault mm/memory.c:5047 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x1b1b/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f60b9a7c6e2
RSP: 002b:00007ffeff584a10 EFLAGS: 00010202
RAX: 00007f60b7814000 RBX: 000055556d31faa0 RCX: 0000000000000006
RDX: 0000000000001736 RSI: 000055556d31e868 RDI: 0000000000000040
RBP: 00007ffeff584f10 R08: 000055556d31e880 R09: 000000000000008c
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffeff584d50
R13: 00007ffeff584b40 R14: 585858582e7a7973 R15: 00007ffeff584a90
 </TASK>
INFO: task syz.9.1683:9379 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.1683      state:D stack:26288 pid:9379  ppid:7751   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 do_shared_fault mm/memory.c:4694 [inline]
 do_fault mm/memory.c:4762 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f9c450727a9
RSP: 002b:00007fff6be16a20 EFLAGS: 00010202
RAX: 0000001b2fc24000 RBX: ffffffff81395da6 RCX: 0000001b2fc23ff8
RDX: 00000000005ffde8 RSI: 00000000005ffde8 RDI: 00007f9c45f55700
RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f9c45412000
R10: 00007f9c45f55700 R11: 0000000000000000 R12: 00007f9c45426038
R13: 0000000000000000 R14: ffffffff813954cc R15: 00007f9c45f55720
 </TASK>
INFO: task syz.8.1684:9384 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.8.1684      state:D stack:26288 pid:9384  ppid:7463   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 do_shared_fault mm/memory.c:4694 [inline]
 do_fault mm/memory.c:4762 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f64dca727a9
RSP: 002b:00007fffeba24f00 EFLAGS: 00010202
RAX: 0000001b2db24000 RBX: ffffffff81c32fd6 RCX: 0000001b2db23ff8
RDX: 00000000005ffde8 RSI: 00000000005ffde8 RDI: 00007f64dd955700
RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f64dce12000
R10: 00007f64dd955700 R11: 0000000000000001 R12: 00007f64dce26128
R13: 0000000000000000 R14: ffffffff81c326bc R15: 00007f64dd955720
 </TASK>
INFO: task syz.3.1686:9390 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1686      state:D stack:26288 pid:9390  ppid:4275   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 do_shared_fault mm/memory.c:4694 [inline]
 do_fault mm/memory.c:4762 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f104f6727a9
RSP: 002b:00007fffd1cdaf40 EFLAGS: 00010202
RAX: 0000001b2fe24000 RBX: ffffffff820719ea RCX: 0000001b2fe23ff8
RDX: 00000000003ffde8 RSI: 00000000003ffde8 RDI: 00007f1050555700
RBP: 0000000000000001 R08: 0000000000000000 R09: 00007f104fa12000
R10: 00007f1050555700 R11: 0000000000000000 R12: 00007f104fa26038
R13: 00000000000016a4 R14: ffffffff820716ea R15: 00007f1050555720
 </TASK>
INFO: task syz.7.1688:9409 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.1688      state:D stack:27632 pid:9409  ppid:6539   flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0x107f/0x4030 kernel/sched/core.c:6563
 schedule+0xb9/0x180 kernel/sched/core.c:6639
 io_schedule+0x7c/0xd0 kernel/sched/core.c:8799
 bit_wait_io+0xd/0xc0 kernel/sched/wait_bit.c:209
 __wait_on_bit+0x9b/0x2c0 kernel/sched/wait_bit.c:49
 out_of_line_wait_on_bit+0x138/0x190 kernel/sched/wait_bit.c:64
 wait_on_bit_io include/linux/wait_bit.h:101 [inline]
 do_get_write_access+0x605/0xf20 fs/jbd2/transaction.c:1115
 jbd2_journal_get_write_access+0x108/0x140 fs/jbd2/transaction.c:1250
 __ext4_journal_get_write_access+0x24b/0x6e0 fs/ext4/ext4_jbd2.c:235
 ext4_reserve_inode_write+0x201/0x290 fs/ext4/inode.c:5945
 __ext4_mark_inode_dirty+0x161/0x7b0 fs/ext4/inode.c:6129
 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6166
 __mark_inode_dirty+0x2e7/0xe80 fs/fs-writeback.c:2500
 generic_update_time fs/inode.c:1946 [inline]
 inode_update_time fs/inode.c:1959 [inline]
 __file_update_time+0x21d/0x240 fs/inode.c:2147
 file_update_time+0x2f3/0x370 fs/inode.c:2178
 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6284
 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009
 do_shared_fault mm/memory.c:4694 [inline]
 do_fault mm/memory.c:4762 [inline]
 handle_pte_fault mm/memory.c:5029 [inline]
 __handle_mm_fault mm/memory.c:5171 [inline]
 handle_mm_fault+0x199c/0x3d40 mm/memory.c:5292
 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338
 handle_page_fault arch/x86/mm/fault.c:1429 [inline]
 exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608
RIP: 0033:0x7f3a05e6baa3
RSP: 002b:00007ffe944c1a50 EFLAGS: 00010246
RAX: 00000000003ffde8 RBX: 0000000000000000 RCX: 0000001b34164000
RDX: 0000001b34124000 RSI: 0000000000400000 RDI: 00007f3a061e0708
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffe944c1ce0
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8cb2e170 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8cb2e990 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xef0 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffffffff8cb2d7e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8cb2d7e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8cb2d7e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6529
2 locks held by getty/4030:
 #0: ffff88814dd08098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41e/0x1360 drivers/tty/n_tty.c:2198
3 locks held by syz-executor/4260:
 #0: ffff88807c1526d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807c1526d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff88807c1526d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283
 #2: ffff88814dd80990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
4 locks held by kworker/u4:6/4332:
 #0: ffff888141e5f138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #1: ffffc900045e7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7b4/0x1160 kernel/workqueue.c:2267
 #2: ffff88814dd7c0e0 (&type->s_umount_key#32){++++}-{3:3}, at: trylock_super+0x1c/0xf0 fs/super.c:415
 #3: ffff88814dd7ec18 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x213/0x2e70 fs/ext4/inode.c:2717
3 locks held by syz.9.1683/9379:
 #0: ffff888023062e58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff888023062e58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff888023062e58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283
 #2: ffff88814dd80990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.8.1684/9384:
 #0: ffff88807e3597d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807e3597d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff88807e3597d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283
 #2: ffff88814dd80990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.3.1686/9390:
 #0: ffff88807e359f58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807e359f58 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff88807e359f58 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283
 #2: ffff88814dd80990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463
3 locks held by syz.7.1688/9409:
 #0: ffff88807c1544d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #0: ffff88807c1544d8 (&mm->mmap_lock){++++}-{3:3}, at: get_mmap_lock_carefully mm/memory.c:5320 [inline]
 #0: ffff88807c1544d8 (&mm->mmap_lock){++++}-{3:3}, at: lock_mm_and_find_vma+0x2e/0x2f0 mm/memory.c:5382
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1897 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:2001 [inline]
 #1: ffff88814dd7c558 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x192/0x10d0 fs/ext4/inode.c:6283
 #2: ffff88814dd80990 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x2014/0x2240 fs/jbd2/transaction.c:463

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf0e/0xf50 kernel/hung_task.c:377
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>