syzbot

INFO: task syz-executor169:4371 blocked for more than 143 seconds.
      Not tainted 5.15.126-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor169 state:D stack:23224 pid: 4371 ppid:  3522 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5026 [inline]
 __schedule+0x12c4/0x4590 kernel/sched/core.c:6372
 schedule+0x11b/0x1f0 kernel/sched/core.c:6455
 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191
 __writeback_inodes_sb_nr+0x2ce/0x370 fs/fs-writeback.c:2662
 try_to_writeback_inodes_sb+0x94/0xb0 fs/fs-writeback.c:2710
 ext4_nonda_switch fs/ext4/inode.c:2933 [inline]
 ext4_da_write_begin+0x228/0xb60 fs/ext4/inode.c:2960
 generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3776
 ext4_buffered_write_iter+0x227/0x360 fs/ext4/file.c:268
 ext4_file_write_iter+0x87c/0x1990
 __kernel_write+0x5b1/0xa60 fs/read_write.c:539
 __dump_emit+0x264/0x3a0 fs/coredump.c:875
 dump_user_range+0x91/0x320 fs/coredump.c:949
 elf_core_dump+0x3c7d/0x4570 fs/binfmt_elf.c:2285
 do_coredump+0x1852/0x31e0 fs/coredump.c:826
 get_signal+0xc06/0x14e0 kernel/signal.c:2875
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:148 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:172
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:208
 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:314
 exc_page_fault+0x342/0x740 arch/x86/mm/fault.c:1544
 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:568
RIP: 0033:0x0
RSP: 002b:00000000200000c8 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fe80117c429
RDX: 0000000000000000 RSI: 00000000200000c0 RDI: 0000000000040000
RBP: 00000000000f4240 R08: 0000000020000200 R09: 00007ffe2b51bda0
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000004213e
R13: 00007fe8011fab20 R14: 00007fe8011fcce0 R15: 00007ffe2b51bd90
 </TASK>

Showing all locks held in the system:
1 lock held by ksoftirqd/1/20:
1 lock held by khungtaskd/27:
 #0: ffffffff8c91f0a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by kworker/u4:3/155:
 #0: ffff8880b9a396d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
 #1: ffffc90001c4fd20 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
2 locks held by kworker/1:2/1053:
 #0: ffff888011c72538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90004b37d20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
3 locks held by kworker/u4:5/1201:
 #0: ffff8880139a4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc9000543fd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
2 locks held by getty/3253:
 #0: ffff8880241a0098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900022a32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
1 lock held by syz-executor169/3619:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3632:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3641:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3658:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3678:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3682:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3700:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3708:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3723:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
2 locks held by syz-executor169/3732:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff8880b9a396d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
2 locks held by syz-executor169/3735:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
1 lock held by syz-executor169/3739:
 #0: ffff88814b51e650 (sb_internal){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1742 [inline]
 #0: ffff88814b51e650 (sb_internal){.+.+}-{0:0}, at: sb_start_intwrite include/linux/fs.h:1859 [inline]
 #0: ffff88814b51e650 (sb_internal){.+.+}-{0:0}, at: ext4_evict_inode+0x375/0x1100 fs/ext4/inode.c:243
1 lock held by syz-executor169/3754:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
2 locks held by syz-executor169/3755:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3764:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3801:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3803:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3808:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff8880b9b396d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
1 lock held by syz-executor169/3816:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3840:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
1 lock held by syz-executor169/3852:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
2 locks held by syz-executor169/3856:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3869:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3879:
 #0: ffff88814b520bd8 (&sbi->s_writepages_rwsem){.+.+}-{0:0}, at: ext4_writepages+0x1f6/0x3d10 fs/ext4/inode.c:2677
 #1: ffff88814b5223f8 (&journal->j_checkpoint_mutex){+.+.}-{3:3}, at: __jbd2_log_wait_for_space+0x213/0x760 fs/jbd2/checkpoint.c:88
2 locks held by syz-executor169/3887: