bcachefs (loop3): Detected missing
bcachefs (loop3): Detected missing backpointers in bucket 34, now have 1/128 with missing
Unable to handle kernel paging request at virtual address ffff60021a432314
KASAN: probably wild-memory-access in range [0xffff0010d21918a0-0xffff0010d21918a7]
Mem abort info:
  ESR = 0x0000000096000005
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x05: level 1 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000005, ISS2 = 0x00000000
  CM = 0, WnR = 0, TnD = 0, TagAccess = 0
  GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000207144000
[ffff60021a432314] pgd=0000000000000000, p4d=000000023397b003, pud=0000000000000000
Internal error: Oops: 0000000096000005 [#1]  SMP
Modules linked in:
CPU: 1 UID: 0 PID: 7529 Comm: bch-copygc/loop Not tainted 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline]
pc : bch2_bucket_bitmap_test fs/bcachefs/backpointers.h:194 [inline]
pc : bch2_bucket_is_movable fs/bcachefs/movinggc.c:78 [inline]
pc : bch2_copygc_get_buckets fs/bcachefs/movinggc.c:157 [inline]
pc : bch2_copygc+0xab4/0x3460 fs/bcachefs/movinggc.c:221
lr : rcu_read_unlock include/linux/rcupdate.h:873 [inline]
lr : class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
lr : bch2_dev_tryget_noerror fs/bcachefs/sb-members.h:241 [inline]
lr : bch2_dev_tryget fs/bcachefs/sb-members.h:245 [inline]
lr : bch2_bucket_is_movable fs/bcachefs/movinggc.c:74 [inline]
lr : bch2_copygc_get_buckets fs/bcachefs/movinggc.c:157 [inline]
lr : bch2_copygc+0xa7c/0x3460 fs/bcachefs/movinggc.c:221
sp : ffff8000a3bb74c0
x29: ffff8000a3bb7920 x28: 0000008000000022 x27: ffff8000a3bb76c8
x26: dfff800000000000
 x25: ffff8000a3bb7cf8 x24: 0000000000000000
x23: ffff0000d5f52000
 x22: 0000000000000000 x21: ffff000107300000
x20: ffff0010d21918a0 x19: ffff00010938a728
 x18: 00000000ffffffff
x17: ffff800093363000
 x16: ffff80008aefcb18 x15: 0000000000000001
x14: 1fffe0001abea408 x13: 0000000000000000 x12: 0000000000000000

x11: ffff60001abea409 x10: 0000000000ff0100
 x9 : 0000001000000000
x8 : 1fffe0021a432314 x7 : ffff800082a0df54 x6 : 0000000000000000
x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff800082a0edd4
x2 : 0000000000000001 x1 : 0000000000000080 x0 : ffff0000c6f81e80
Call trace:
 generic_test_bit include/asm-generic/bitops/generic-non-atomic.h:128 [inline] (P)
 bch2_bucket_bitmap_test fs/bcachefs/backpointers.h:194 [inline] (P)
 bch2_bucket_is_movable fs/bcachefs/movinggc.c:78 [inline] (P)
 bch2_copygc_get_buckets fs/bcachefs/movinggc.c:157 [inline] (P)
 bch2_copygc+0xab4/0x3460 fs/bcachefs/movinggc.c:221 (P)
 bch2_copygc_thread+0x898/0xd8c fs/bcachefs/movinggc.c:409
 kthread+0x5fc/0x75c kernel/kthread.c:464
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:847
Code: d343fd29 927da529 8b090114 d343fe88 (387a6908) 
---[ end trace 0000000000000000 ]---
----------------
Code disassembly (best guess):
   0:	d343fd29 	lsr	x9, x9, #3
   4:	927da529 	and	x9, x9, #0x1ffffffffff8
   8:	8b090114 	add	x20, x8, x9
   c:	d343fe88 	lsr	x8, x20, #3
* 10:	387a6908 	ldrb	w8, [x8, x26] <-- trapping instruction