syzbot

workqueue: max_active 2097158 requested for btrfs-readahead is out of range, clamping between 1 and 512
BTRFS info (device loop0): enabling ssd optimizations
BTRFS error (device loop0): unrecognized mount option 'rescuehfs'
Unable to handle kernel paging request at virtual address dfff800000000000
Mem abort info:
  ESR = 0x0000000096000006
  EC = 0x25: DABT (current EL), IL = 32 bits
  SET = 0, FnV = 0
  EA = 0, S1PTW = 0
  FSC = 0x06: level 2 translation fault
Data abort info:
  ISV = 0, ISS = 0x00000006
  CM = 0, WnR = 0
[dfff800000000000] address between user and kernel address ranges
Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP
Modules linked in:
CPU: 1 PID: 4022 Comm: syz-executor165 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : backup_super_roots fs/btrfs/disk-io.c:2007 [inline]
pc : write_all_supers+0xcc0/0x35a8 fs/btrfs/disk-io.c:4154
lr : lowmem_page_address include/linux/mm.h:1612 [inline]
lr : btrfs_header_level fs/btrfs/ctree.h:2194 [inline]
lr : backup_super_roots fs/btrfs/disk-io.c:2005 [inline]
lr : write_all_supers+0xbf8/0x35a8 fs/btrfs/disk-io.c:4154
sp : ffff80001be47240
x29: ffff80001be475c0 x28: 1fffe0001ad31008 x27: ffff800013b48000
x26: 1ffff000027690d0 x25: dfff800000000000 x24: 0000000000000000
x23: ffff0000c2b8cb2b x22: 0000000000000004 x21: dfff800000000000
x20: 0000000000000000 x19: ffff0000d6988040 x18: 0000000000000000
x17: ffff800016cf0000 x16: ffff8000082d4c48 x15: ffff8000167d04c0
x14: ffff0000d623c080 x13: 0000000000000000 x12: 0000000000ff0100
x11: 0000000000000000 x10: 0000000000000000 x9 : ffff0000d6988000
x8 : 0000000000000000 x7 : 0000000000000000 x6 : 000000000000003f
x5 : 0000000000000040 x4 : ffffffffffffffd0 x3 : 0000000000000010
x2 : 0000000000000003 x1 : 0000000000000000 x0 : ffff0000cf62b860
Call trace:
 backup_super_roots fs/btrfs/disk-io.c:2007 [inline]
 write_all_supers+0xcc0/0x35a8 fs/btrfs/disk-io.c:4154
 btrfs_commit_transaction+0x1674/0x3044 fs/btrfs/transaction.c:2464
 btrfs_set_free_space_cache_v1_active+0x78/0x23c fs/btrfs/free-space-cache.c:4001
 btrfs_remount_cleanup fs/btrfs/super.c:1913 [inline]
 btrfs_remount+0x5ec/0x12b8 fs/btrfs/super.c:2116
 legacy_reconfigure+0xf8/0x110 fs/fs_context.c:634
 reconfigure_super+0x1d4/0x6f4 fs/super.c:938
 do_remount fs/namespace.c:2666 [inline]
 path_mount+0xc80/0x1000 fs/namespace.c:3332
 do_mount fs/namespace.c:3353 [inline]
 __do_sys_mount fs/namespace.c:3561 [inline]
 __se_sys_mount fs/namespace.c:3538 [inline]
 __arm64_sys_mount+0x514/0x5e4 fs/namespace.c:3538
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142
 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181
 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608
 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584
Code: aa1303e0 97a7ae7e f9400274 d343fe88 (38796908) 
---[ end trace 1a7d1d1327a1316e ]---
----------------
Code disassembly (best guess):
   0:	aa1303e0 	mov	x0, x19
   4:	97a7ae7e 	bl	0xfffffffffe9eb9fc
   8:	f9400274 	ldr	x20, [x19]
   c:	d343fe88 	lsr	x8, x20, #3
* 10:	38796908 	ldrb	w8, [x8, x25] <-- trapping instruction