INFO: task syz-executor408:5961 blocked for more than 143 seconds.
      Not tainted 6.3.0-rc7-syzkaller-g14f8db1c0f9a #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor408 state:D stack:0     pid:5961  ppid:5960   flags:0x00000001
Call trace:
 __switch_to+0x320/0x754 arch/arm64/kernel/process.c:556
 context_switch kernel/sched/core.c:5307 [inline]
 __schedule+0x103c/0x1e2c kernel/sched/core.c:6625
 schedule+0xc4/0x170 kernel/sched/core.c:6701
 wait_on_state fs/btrfs/extent-io-tree.c:707 [inline]
 wait_extent_bit+0x4cc/0x620 fs/btrfs/extent-io-tree.c:751
 lock_extent+0x19c/0x248 fs/btrfs/extent-io-tree.c:1742
 btrfs_page_mkwrite+0x5fc/0xc84 fs/btrfs/inode.c:8163
 do_page_mkwrite+0x144/0x37c mm/memory.c:2925
 wp_page_shared mm/memory.c:3274 [inline]
 do_wp_page+0x364/0x28d8 mm/memory.c:3356
 handle_pte_fault mm/memory.c:4941 [inline]
 __handle_mm_fault mm/memory.c:5065 [inline]
 handle_mm_fault+0x1b28/0x3e3c mm/memory.c:5211
 __do_page_fault arch/arm64/mm/fault.c:512 [inline]
 do_page_fault+0x634/0xac4 arch/arm64/mm/fault.c:612
 do_mem_abort+0x74/0x200 arch/arm64/mm/fault.c:831
 el1_abort+0x3c/0x5c arch/arm64/kernel/entry-common.c:367
 el1h_64_sync_handler+0x60/0xac arch/arm64/kernel/entry-common.c:427
 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:586
 __arch_copy_to_user+0x88/0x234 arch/arm64/lib/copy_template.S:90
 emit_last_fiemap_cache fs/btrfs/extent_io.c:3036 [inline]
 extent_fiemap+0x16c8/0x1a44 fs/btrfs/extent_io.c:3563
 btrfs_fiemap+0x154/0x1c0 fs/btrfs/inode.c:7835
 ioctl_fiemap fs/ioctl.c:219 [inline]
 do_vfs_ioctl+0x194c/0x26f8 fs/ioctl.c:810
 __do_sys_ioctl fs/ioctl.c:868 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __arm64_sys_ioctl+0xe4/0x1c8 fs/ioctl.c:856
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193
 el0_svc+0x4c/0x15c arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffff800015f3f4d0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by rcu_tasks_trace/13:
 #0: ffff800015f3fcd0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:510
1 lock held by khungtaskd/28:
 #0: ffff800015f3f300 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:326
2 locks held by getty/5686:
 #0: ffff0000d4ba7098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80001acd02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1210 drivers/tty/n_tty.c:2177
4 locks held by syz-executor408/5961:
 #0: ffff0000de769848 (&sb->s_type->i_mutex_key#16){++++}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
 #0: ffff0000de769848 (&sb->s_type->i_mutex_key#16){++++}-{3:3}, at: btrfs_inode_lock+0x68/0xe0 fs/btrfs/inode.c:169
 #1: ffff0000d9760948 (&mm->mmap_lock){++++}-{3:3}, at: mmap_read_trylock include/linux/mmap_lock.h:136 [inline]
 #1: ffff0000d9760948 (&mm->mmap_lock){++++}-{3:3}, at: do_page_fault+0x2dc/0xac4 arch/arm64/mm/fault.c:593
 #2: ffff0000c7928558 (sb_pagefaults){.+.+}-{0:0}, at: do_page_mkwrite+0x144/0x37c mm/memory.c:2925
 #3: ffff0000de7696d0 (&ei->i_mmap_lock){.+.+}-{3:3}, at: btrfs_page_mkwrite+0x4a4/0xc84 fs/btrfs/inode.c:8152

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