INFO: task jbd2/sda1-8:4955 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:26088 pid:4955  tgid:4955  ppid:2      task_flags:0x240040 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 __wait_on_buffer+0x64/0x70 fs/buffer.c:123
 wait_on_buffer include/linux/buffer_head.h:420 [inline]
 jbd2_journal_commit_transaction+0x388a/0x6870 fs/jbd2/commit.c:837
 kjournald2+0x200/0x760 fs/jbd2/journal.c:201
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task syz-executor:5614 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:22856 pid:5614  tgid:5614  ppid:5613   task_flags:0x440100 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375
 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550
 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587
 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623
 generic_update_time fs/inode.c:2192 [inline]
 file_update_time_flags+0x46b/0x500 fs/inode.c:2422
 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753
 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 wp_page_shared mm/memory.c:4069 [inline]
 do_wp_page+0xa77/0x4350 mm/memory.c:4288
 handle_pte_fault mm/memory.c:6427 [inline]
 __handle_mm_fault+0x1ab6/0x2a00 mm/memory.c:6549
 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718
 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f9b4467b3e7
RSP: 002b:00007fff766dc340 EFLAGS: 00010246
RAX: 00007f9b42938000 RBX: 00005555742ca690 RCX: 0000000000000000
RDX: 0000000000002fb4 RSI: 00005555742d6558 RDI: 0000000000000001
RBP: 00007fff766dc840 R08: 00000000000000ff R09: 00005555742d6560
R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff766dc680
R13: 00007fff766dc470 R14: 585858582e7a7973 R15: 00007fff766dc3c0
 </TASK>
INFO: task kworker/u8:18:6537 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/u8:18   state:D stack:24408 pid:6537  tgid:6537  ppid:2      task_flags:0x4248060 flags:0x00080000
Workqueue: writeback wb_workfn (flush-8:0)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375
 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550
 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587
 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623
 mark_inode_dirty_sync include/linux/fs.h:2218 [inline]
 dquot_claim_block include/linux/quotaops.h:356 [inline]
 ext4_da_update_reserve_space+0x2ac/0x730 fs/ext4/inode.c:373
 ext4_es_insert_extent+0xa6f/0x10f0 fs/ext4/extents_status.c:1003
 ext4_map_create_blocks+0x266/0x5e0 fs/ext4/inode.c:671
 ext4_map_blocks+0x46b/0xd30 fs/ext4/inode.c:824
 mpage_map_one_extent fs/ext4/inode.c:2396 [inline]
 mpage_map_and_submit_extent fs/ext4/inode.c:2490 [inline]
 ext4_do_writepages+0x2313/0x3f20 fs/ext4/inode.c:2948
 ext4_writepages+0x347/0x790 fs/ext4/inode.c:3042
 do_writepages+0x278/0x600 mm/page-writeback.c:2575
 __writeback_single_inode+0x164/0x1350 fs/fs-writeback.c:1764
 writeback_sb_inodes+0x766/0x1c60 fs/fs-writeback.c:2056
 __writeback_inodes_wb+0xf8/0x2d0 fs/fs-writeback.c:2132
 wb_writeback+0x720/0xb90 fs/fs-writeback.c:2243
 wb_check_old_data_flush fs/fs-writeback.c:2347 [inline]
 wb_do_writeback fs/fs-writeback.c:2400 [inline]
 wb_workfn+0x8dd/0xc00 fs/fs-writeback.c:2428
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
INFO: task syz.3.702:9415 blocked in I/O wait for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.702       state:D stack:24792 pid:9415  tgid:9415  ppid:5630   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375
 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550
 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587
 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623
 generic_update_time fs/inode.c:2192 [inline]
 file_update_time_flags+0x46b/0x500 fs/inode.c:2422
 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753
 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 do_shared_fault mm/memory.c:5969 [inline]
 do_fault+0x3b5/0x1750 mm/memory.c:6031
 do_pte_missing mm/memory.c:4550 [inline]
 handle_pte_fault mm/memory.c:6411 [inline]
 __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549
 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718
 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f9b99271500
RSP: 002b:00007ffead593f20 EFLAGS: 00010202
RAX: 0000001b349d8000 RBX: ffffffff82872b60 RCX: 0000001b349d7ff8
RDX: 0000001b34624220 RSI: 0000000000000008 RDI: 00007f9b9a145720
RBP: 0000000000000018 R08: 00007f9b99600000 R09: 00007f9b99602000
R10: 0000000082872b64 R11: 000000000000000c R12: 00007f9b99616308
R13: 0000000000000017 R14: ffffffff82872803 R15: 00007f9b9a145720
 </TASK>
INFO: task syz.2.704:9426 blocked in I/O wait for more than 144 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.704       state:D stack:26152 pid:9426  tgid:9426  ppid:5629   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375
 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550
 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587
 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623
 generic_update_time fs/inode.c:2192 [inline]
 file_update_time_flags+0x46b/0x500 fs/inode.c:2422
 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753
 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 do_shared_fault mm/memory.c:5969 [inline]
 do_fault+0x3b5/0x1750 mm/memory.c:6031
 do_pte_missing mm/memory.c:4550 [inline]
 handle_pte_fault mm/memory.c:6411 [inline]
 __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549
 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718
 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f2098271500
RSP: 002b:00007ffdf6619d40 EFLAGS: 00010202
RAX: 0000001b34aea000 RBX: ffffffff8290e1fb RCX: 0000001b34ae9ff8
RDX: 0000001b34524220 RSI: 0000000000000008 RDI: 00007f2099145720
RBP: 0000000000000012 R08: 00007f2098600000 R09: 00007f2098602000
R10: 000000008290e1ff R11: 0000000000000017 R12: 00007f2098616128
R13: 0000000000000011 R14: ffffffff8290ea9b R15: 00007f2099145720
 </TASK>
INFO: task syz.1.706:9438 blocked in I/O wait for more than 145 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.706       state:D stack:27128 pid:9438  tgid:9438  ppid:5627   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375
 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550
 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587
 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623
 generic_update_time fs/inode.c:2192 [inline]
 file_update_time_flags+0x46b/0x500 fs/inode.c:2422
 ext4_page_mkwrite+0x324/0x1890 fs/ext4/inode.c:6753
 do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 do_shared_fault mm/memory.c:5969 [inline]
 do_fault+0x3b5/0x1750 mm/memory.c:6031
 do_pte_missing mm/memory.c:4550 [inline]
 handle_pte_fault mm/memory.c:6411 [inline]
 __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6549
 handle_mm_fault+0x36d/0xa20 mm/memory.c:6718
 do_user_addr_fault+0x5a3/0x12f0 arch/x86/mm/fault.c:1334
 handle_page_fault arch/x86/mm/fault.c:1474 [inline]
 exc_page_fault+0x6f/0xd0 arch/x86/mm/fault.c:1527
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7fd6d2a71500
RSP: 002b:00007ffd731d61d0 EFLAGS: 00010202
RAX: 0000001b34823000 RBX: ffffffff825ca39d RCX: 0000001b34822ff8
RDX: 0000001b3442421c RSI: 0000000000000008 RDI: 00007fd6d3945720
RBP: 0000000000000038 R08: 00007fd6d2e00000 R09: 00007fd6d2e02000
R10: 00000000825ca3a1 R11: 0000000000000001 R12: 00007fd6d2e16038
R13: 0000000000000037 R14: ffffffff825ca99c R15: 00007fd6d3945720
 </TASK>
INFO: task syz.0.707:9440 blocked in I/O wait for more than 145 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.707       state:D stack:27336 pid:9440  tgid:9440  ppid:5628   task_flags:0x440040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5387 [inline]
 __schedule+0x10e9/0x6820 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7282
 io_schedule+0x8a/0xf0 kernel/sched/core.c:8109
 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250
 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52
 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67
 wait_on_bit_io include/linux/wait_bit.h:105 [inline]
 do_get_write_access+0x84f/0x1220 fs/jbd2/transaction.c:1113
 jbd2_journal_get_write_access+0x1d6/0x280 fs/jbd2/transaction.c:1263
 __ext4_journal_get_write_access+0x6a/0x340 fs/ext4/ext4_jbd2.c:241
 ext4_reserve_inode_write+0x1b7/0x330 fs/ext4/inode.c:6375
 __ext4_mark_inode_dirty+0x18f/0x890 fs/ext4/inode.c:6550
 ext4_dirty_inode+0xd9/0x130 fs/ext4/inode.c:6587
 __mark_inode_dirty+0x1f3/0x1720 fs/fs-writeback.c:2623
 generic_update_time fs/inode.c:2192 [inline]
 touch_atime+0x642/0x7a0 fs/inode.c:2267
 file_accessed include/linux/fs.h:2264 [inline]
 ext4_file_mmap_prepare+0x56d/0x670 fs/ext4/file.c:840
 vfs_mmap_prepare include/linux/fs.h:2076 [inline]
 call_mmap_prepare mm/vma.c:2672 [inline]
 __mmap_region+0xe98/0x2da0 mm/vma.c:2755
 mmap_region+0x527/0x620 mm/vma.c:2856
 do_mmap+0xc63/0x12f0 mm/mmap.c:560
 vm_mmap_pgoff+0x29e/0x470 mm/util.c:581
 ksys_mmap_pgoff+0x3cb/0x610 mm/mmap.c:606
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
 __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f29bd99cb42
RSP: 002b:00007fffd98bb4a8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 0000001b34364000 RCX: 00007f29bd99cb42
RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b34364000
RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000
R10: 0000000000100001 R11: 0000000000000206 R12: 00000000000000c7
R13: 00000000000927c0 R14: 000000000005754d R15: 00007fffd98bb780
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e7e52e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e7e52e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e7e52e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
1 lock held by klogd/4982:
 #0: ffff8880b843b3e0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2c/0x140 kernel/sched/core.c:652
2 locks held by getty/5383:
 #0: ffff88802a2f60a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211
3 locks held by syz-executor/5614:
 #0: ffff8880767c6948 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
 #1: ffff888038638508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 #2: ffff88802cec0938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444
6 locks held by kworker/u8:18/6537:
 #0: ffff888020ae8940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3277
 #1: ffffc90005fbfd08 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3278
 #2: ffff8880386380d8 (&type->s_umount_key#33){++++}-{4:4}, at: super_trylock_shared+0x1e/0xf0 fs/super.c:565
 #3: ffff888038656c18 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: do_writepages+0x278/0x600 mm/page-writeback.c:2575
 #4: ffff88802cec0938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444
 #5: ffff888078501e30 (&ei->i_data_sem){++++}-{4:4}, at: ext4_map_blocks+0x45a/0xd30 fs/ext4/inode.c:823
3 locks held by syz.3.702/9415:
 #0: ffff88807e47e308 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
 #1: ffff888038638508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 #2: ffff88802cec0938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444
3 locks held by syz.2.704/9426:
 #0: ffff8880356b6bc8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
 #1: ffff888038638508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 #2: ffff88802cec0938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444
3 locks held by syz.1.706/9438:
 #0: ffff888078cefd08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x11d/0x590 mm/mmap_lock.c:310
 #1: ffff888038638508 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x17a/0x440 mm/memory.c:3668
 #2: ffff88802cec0938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444
3 locks held by syz.0.707/9440:
 #0: ffff88813fe7a7f8 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:554 [inline]
 #0: ffff88813fe7a7f8 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1f5/0x470 mm/util.c:579
 #1: ffff888038638410 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2264 [inline]
 #1: ffff888038638410 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x56d/0x670 fs/ext4/file.c:840
 #2: ffff88802cec0938 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0xfaa/0x13a0 fs/jbd2/transaction.c:444

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 __sys_info lib/sys_info.c:157 [inline]
 sys_info+0x141/0x190 lib/sys_info.c:165
 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
 watchdog+0xcb1/0x1030 kernel/hung_task.c:561
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 3330 Comm: kworker/u8:10 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:stack_trace_consume_entry+0x46/0x170 kernel/stacktrace.c:86
Code: ea 03 48 83 ec 08 0f b6 04 02 84 c0 74 08 3c 03 0f 8e e7 00 00 00 48 8d 7b 08 8b 6b 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa <48> c1 ea 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e ad 00 00 00 31 c0
RSP: 0018:ffffc9000f11f6d0 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: ffffc9000f11f7b0 RCX: ffffc9000f11f644
RDX: ffffc9000f11f7b8 RSI: ffffffff8269268a RDI: ffffc9000f11f7b8
RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000017470 R12: ffffffff81f24070
R13: ffffc9000f11f7b0 R14: 0000000000000000 R15: ffff88803522bd80
FS:  0000000000000000(0000) GS:ffff88812437d000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055b9aef24168 CR3: 000000000e596000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 arch_stack_walk+0x88/0xf0 arch/x86/kernel/stacktrace.c:27
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4569 [inline]
 slab_alloc_node mm/slub.c:4898 [inline]
 kmem_cache_alloc_node_noprof+0x25a/0x6f0 mm/slub.c:4950
 __alloc_skb+0x140/0x710 net/core/skbuff.c:702
 alloc_skb include/linux/skbuff.h:1383 [inline]
 nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
 nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
 nsim_dev_trap_report_work+0x2af/0xd20 drivers/net/netdevsim/dev.c:922
 process_one_work+0xa0e/0x1980 kernel/workqueue.c:3302
 process_scheduled_works kernel/workqueue.c:3385 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3466
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	03 48 83             	add    -0x7d(%rax),%ecx
   3:	ec                   	in     (%dx),%al
   4:	08 0f                	or     %cl,(%rdi)
   6:	b6 04                	mov    $0x4,%dh
   8:	02 84 c0 74 08 3c 03 	add    0x33c0874(%rax,%rax,8),%al
   f:	0f 8e e7 00 00 00    	jle    0xfc
  15:	48 8d 7b 08          	lea    0x8(%rbx),%rdi
  19:	8b 6b 10             	mov    0x10(%rbx),%ebp
  1c:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  23:	fc ff df
  26:	48 89 fa             	mov    %rdi,%rdx
* 29:	48 c1 ea 03          	shr    $0x3,%rdx <-- trapping instruction
  2d:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax
  31:	84 c0                	test   %al,%al
  33:	74 08                	je     0x3d
  35:	3c 03                	cmp    $0x3,%al
  37:	0f 8e ad 00 00 00    	jle    0xea
  3d:	31 c0                	xor    %eax,%eax