INFO: task jbd2/sda1-8:4919 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:4919 tgid:4919 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258 __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:418 [inline] jbd2_journal_commit_transaction+0x2f26/0x5ba0 fs/jbd2/commit.c:834 kjournald2+0x3bc/0x750 fs/jbd2/journal.c:200 kthread+0x38b/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:5578 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:21832 pid:5578 tgid:5578 ppid:5577 task_flags:0x440100 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258 __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:106 [inline] do_get_write_access+0x671/0x1090 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:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 wp_page_shared mm/memory.c:4217 [inline] do_wp_page+0x20a7/0x3d20 mm/memory.c:4440 handle_pte_fault mm/memory.c:6582 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xd69/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/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: 0033:0x7f1c2332c6e2 RSP: 002b:00007fffa02898e0 EFLAGS: 00010202 RAX: 00007f1c21388000 RBX: 0000555558ea2ae0 RCX: 0000000000000006 RDX: 0000000000002f22 RSI: 0000555558eaae78 RDI: 0000000000000040 RBP: 00007fffa0289de0 R08: 0000555558eaaf98 R09: 000000000000009b R10: 0000000000000000 R11: 0000000000000202 R12: 00007fffa0289c20 R13: 00007fffa0289a10 R14: 585858582e7a7973 R15: 00007fffa0289960 INFO: task syz.9.6869:21729 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.9.6869 state:D stack:26920 pid:21729 tgid:21729 ppid:20752 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258 __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:106 [inline] do_get_write_access+0x671/0x1090 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:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] touch_atime+0x568/0x670 fs/inode.c:2328 file_accessed include/linux/fs.h:2277 [inline] ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:901 vfs_mmap_prepare include/linux/fs.h:2069 [inline] call_mmap_prepare mm/vma.c:2776 [inline] __mmap_region mm/vma.c:2865 [inline] mmap_region+0xea5/0x2220 mm/vma.c:2966 do_mmap+0xe0e/0x1310 mm/mmap.c:573 vm_mmap_pgoff+0x275/0x4e0 mm/util.c:581 ksys_mmap_pgoff+0x4a6/0x720 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: 0033:0x7f0a0769dec2 RSP: 002b:00007fffe2475f88 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000001b2d864000 RCX: 00007f0a0769dec2 RDX: 0000000000000003 RSI: 00000000005c0000 RDI: 0000001b2d864000 RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000100001 R11: 0000000000000206 R12: 0000000000000045 R13: 00000000000927c0 R14: 00000000000c3f9d R15: 00007fffe2476260 INFO: task syz.5.6870:21730 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.5.6870 state:D stack:26056 pid:21730 tgid:21730 ppid:11089 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258 __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:106 [inline] do_get_write_access+0x671/0x1090 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:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/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: 0033:0x7fea8a03baa3 RSP: 002b:00007fff63a38270 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000001b30c64000 RDX: 0000001b30c24000 RSI: 0000000000600000 RDI: 00007fea8a3b0708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007fff63a38500 INFO: task syz.8.6871:21731 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.8.6871 state:D stack:27160 pid:21731 tgid:21731 ppid:16941 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258 __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:106 [inline] do_get_write_access+0x671/0x1090 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:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] touch_atime+0x568/0x670 fs/inode.c:2328 file_accessed include/linux/fs.h:2277 [inline] ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:901 vfs_mmap_prepare include/linux/fs.h:2069 [inline] call_mmap_prepare mm/vma.c:2776 [inline] __mmap_region mm/vma.c:2865 [inline] mmap_region+0xea5/0x2220 mm/vma.c:2966 do_mmap+0xe0e/0x1310 mm/mmap.c:573 vm_mmap_pgoff+0x275/0x4e0 mm/util.c:581 ksys_mmap_pgoff+0x4a6/0x720 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: 0033:0x7f1d6359dec2 RSP: 002b:00007ffd5afd0068 EFLAGS: 00000206 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 0000001b2ef64000 RCX: 00007f1d6359dec2 RDX: 0000000000000003 RSI: 00000000003c0000 RDI: 0000001b2ef64000 RBP: 0000000000100001 R08: 0000000000000004 R09: 0000000000040000 R10: 0000000000100001 R11: 0000000000000206 R12: 000000000000018e R13: 00000000000927c0 R14: 00000000000c3fe0 R15: 00007ffd5afd0340 INFO: task syz.7.6872:21732 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.7.6872 state:D stack:26056 pid:21732 tgid:21732 ppid:15520 task_flags:0x440040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5526 [inline] __schedule+0x16d9/0x5700 kernel/sched/core.c:7277 __schedule_loop kernel/sched/core.c:7354 [inline] schedule+0x164/0x2b0 kernel/sched/core.c:7369 io_schedule+0x80/0xe0 kernel/sched/core.c:8213 bit_wait_io+0x11/0xd0 kernel/sched/wait_bit.c:258 __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:106 [inline] do_get_write_access+0x671/0x1090 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:6514 __ext4_mark_inode_dirty+0x146/0x7b0 fs/ext4/inode.c:6699 ext4_dirty_inode+0xd0/0x110 fs/ext4/inode.c:6736 __mark_inode_dirty+0x3a8/0x13b0 fs/fs-writeback.c:2729 generic_update_time fs/inode.c:2253 [inline] file_update_time_flags+0x39f/0x450 fs/inode.c:2483 ext4_page_mkwrite+0x225/0x1150 fs/ext4/inode.c:6902 do_page_mkwrite+0x14a/0x310 mm/memory.c:3816 do_shared_fault mm/memory.c:6076 [inline] do_fault mm/memory.c:6138 [inline] do_pte_missing+0x734/0x28f0 mm/memory.c:4700 handle_pte_fault mm/memory.c:6558 [inline] __handle_mm_fault mm/memory.c:6707 [inline] handle_mm_fault+0xf64/0x28c0 mm/memory.c:6876 do_user_addr_fault+0xa4f/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: 0033:0x7fd1e131baa3 RSP: 002b:00007ffeb0b994b0 EFLAGS: 00010246 RAX: 00000000005ffde8 RBX: 0000000000000000 RCX: 0000001b2e364000 RDX: 0000001b2e324000 RSI: 0000000000600000 RDI: 00007fd1e1690708 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00007ffeb0b99740 Showing all locks held in the system: locks held by pr/ttyS0/17: 3, last CPU#1: #0: ffffffff8e09d7b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline] #0: ffffffff8e09d7b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline] #0: ffffffff8e09d7b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x30/0x60 kernel/printk/printk.c:291 #1: ffffffff99ea21f8 (&port_lock_key){+.+.}-{3:3}, at: nbcon_emit_one kernel/printk/nbcon.c:1137 [inline] #1: ffffffff99ea21f8 (&port_lock_key){+.+.}-{3:3}, at: nbcon_kthread_func+0x64c/0x880 kernel/printk/nbcon.c:1271 #2: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rtlock_slowlock kernel/locking/rtmutex.c:1921 [inline] #2: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rtlock_lock kernel/locking/spinlock_rt.c:43 [inline] #2: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline] #2: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x157/0x400 kernel/locking/spinlock_rt.c:57 locks held by khungtaskd/38: 1, last CPU#0: #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6871 locks held by kworker/u8:18/3345: 4, on CPU#0: #0: ffff88801ee9e938 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffff88801ee9e938 ((wq_completion)writeback){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffff88801ee9e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #0: ffff88801ee9e938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #1: ffffc9000f957c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #1: ffffc9000f957c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #1: ffffc9000f957c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3361 [inline] #1: ffffc9000f957c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x97a/0x1630 kernel/workqueue.c:3479 #2: ffff888036dc60e0 (&type->s_umount_key#34){++++}-{4:4}, at: super_trylock_shared+0x23/0xf0 fs/super.c:674 #3: ffff888036d20d98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: percpu_down_read include/linux/percpu-rwsem.h:77 [inline] #3: ffff888036d20d98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages_down_read fs/ext4/ext4.h:1887 [inline] #3: ffff888036d20d98 (&sbi->s_writepages_rwsem){++++}-{0:0}, at: ext4_writepages+0x205/0x3b0 fs/ext4/inode.c:3031 locks held by syslogd/4939: 1, on CPU#0: #0: ffff888029ba80d8 (&si->socket.wq.wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline] #0: ffff888029ba80d8 (&si->socket.wq.wait){+.+.}-{3:3}, at: finish_wait+0xbe/0x1e0 kernel/sched/wait.c:395 locks held by klogd/4946: 3, last CPU#0: #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:309 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1c3c80 (rcu_read_lock){....}-{1:3}, at: sock_def_readable+0xae/0x550 net/core/sock.c:3658 #1: ffff888029ba80d8 (&si->socket.wq.wait){+.+.}-{3:3}, at: psi_task_switch+0x57/0x790 kernel/sched/psi.c:933 #2: ffff8880b863c320 (&rq->__lock){-...}-{2:2}, at: raw_spin_rq_lock_nested+0x2d/0x160 kernel/sched/core.c:677 locks held by getty/5344: 2, on CPU#0: #0: ffff888032e1a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc900044c32e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x460/0x1360 drivers/tty/n_tty.c:2211 locks held by syz-executor/5578: 3, on CPU#1: #0: ffff88803b6391c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888036204bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.9.6869/21729: 3, on CPU#0: #0: ffff888036ea2cb0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline] #0: ffff888036ea2cb0 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1e0/0x4e0 mm/util.c:579 #1: ffff888036dc6510 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2277 [inline] #1: ffff888036dc6510 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:901 #2: ffff888036204bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.5.6870/21730: 3, on CPU#1: #0: ffff888036b4de48 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888036204bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.8.6871/21731: 3, on CPU#1: #0: ffff888036ea3a30 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:562 [inline] #0: ffff888036ea3a30 (&mm->mmap_lock){++++}-{4:4}, at: vm_mmap_pgoff+0x1e0/0x4e0 mm/util.c:579 #1: ffff888036dc6510 (sb_writers#4){.+.+}-{0:0}, at: file_accessed include/linux/fs.h:2277 [inline] #1: ffff888036dc6510 (sb_writers#4){.+.+}-{0:0}, at: ext4_file_mmap_prepare+0x286/0x460 fs/ext4/file.c:901 #2: ffff888036204bb0 (jbd2_handle){++++}-{0:0}, at: start_this_handle+0x1fbf/0x2200 fs/jbd2/transaction.c:444 locks held by syz.7.6872/21732: 3, on CPU#1: #0: ffff888040db0d08 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x1d1/0x500 mm/mmap_lock.c:310 #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs/super.h:19 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs/super.h:159 [inline] #1: ffff888036dc6688 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x203/0x1150 fs/ext4/inode.c:6901 #2: ffff888036204bb0 (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: 38 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: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:353 [inline] watchdog+0xfd7/0x1030 kernel/hung_task.c:561 kthread+0x38b/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: 17 Comm: pr/ttyS0 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:409 Code: e8 1e fa 64 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 6f e7 d0 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:ffffc900001678b8 EFLAGS: 00000202 RAX: 1ffffffff33d4400 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000 R10: dffffc0000000000 R11: ffffffff8561a0f0 R12: dffffc0000000000 R13: 0000000000000000 R14: ffffffff99ea2220 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888125ccb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056295c6830f0 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:2013 serial8250_fifo_wait_for_lsr_thre drivers/tty/serial/8250/8250_port.c:3270 [inline] __serial8250_console_fifo_write+0xd0/0x3f0 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+0xac5/0x1230 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+0x38b/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