syzbot

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WARNING: CPU: 1 PID: 6501 at fs/bcachefs/fs-io-buffered.c:464 bch2_writepage_io_done+0x6fc/0x7b4 fs/bcachefs/fs-io-buffered.c:464
Modules linked in:
CPU: 1 UID: 0 PID: 6501 Comm: kworker/u9:2 Not tainted 6.15.0-rc7-syzkaller-gd7fa1af5b33e #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: bcachefs bch2_write_point_do_index_updates
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : bch2_writepage_io_done+0x6fc/0x7b4 fs/bcachefs/fs-io-buffered.c:464
lr : bch2_writepage_io_done+0x6fc/0x7b4 fs/bcachefs/fs-io-buffered.c:464
sp : ffff8000a4b178d0
x29: ffff8000a4b17940 x28: dfff800000000000 x27: 0000000000000003
x26: ffff0000c9b8d7c8 x25: ffff0000c9b8d7c8 x24: ffff0000ddb80000
x23: ffff0000c9b8d920 x22: 0000000000000008 x21: ffff0000c9b8d940
x20: 1fffe00019371b24 x19: 0000000000000c00 x18: 00000000ffffffff
x17: ffff800092f39000 x16: ffff80008ad27e48 x15: 0000000000000006
x14: 1ffff00014962f21 x13: 0000000000000000 x12: 0000000000000000
x11: ffff700014962f27 x10: 0000000000ff0100 x9 : 0000000000000000
x8 : ffff0000d7f55b80 x7 : 0000000000000000 x6 : 0000000000000000
x5 : ffff80009308cef8 x4 : 0000000000000008 x3 : 0000000000000020
x2 : 0000000000000008 x1 : 0000000000000008 x0 : 0000000000000000
Call trace:
 bch2_writepage_io_done+0x6fc/0x7b4 fs/bcachefs/fs-io-buffered.c:464 (P)
 bch2_write_done+0x2a4/0x914 fs/bcachefs/io_write.c:542
 bch2_write_point_do_index_updates+0x7c/0x4f0 fs/bcachefs/io_write.c:708
 process_one_work+0x7e8/0x156c kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x958/0xed8 kernel/workqueue.c:3400
 kthread+0x5fc/0x75c kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847
irq event stamp: 824
hardirqs last  enabled at (823): [<ffff80008addfa48>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:151 [inline]
hardirqs last  enabled at (823): [<ffff80008addfa48>] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:194
hardirqs last disabled at (824): [<ffff80008adb9eb8>] el1_dbg+0x24/0x80 arch/arm64/kernel/entry-common.c:511
softirqs last  enabled at (0): [<ffff8000803acfb0>] copy_process+0x112c/0x318c kernel/fork.c:2375
softirqs last disabled at (0): [<0000000000000000>] 0x0
---[ end trace 0000000000000000 ]---