bcachefs (loop2): starting version 1.7: mi_btree_bitmap opts=metadata_checksum=none,data_checksum=none,compression=lz4,no_splitbrain_check,fsck,fix_errors=ask,norecovery,nojournal_transaction_names,reconstruct_alloc
bcachefs (loop2): recovering from clean shutdown, journal seq 10
bcachefs (loop2): Doing compatible version upgrade from 1.7: mi_btree_bitmap to 1.12: rebalance_work_acct_fix
  running recovery passes: check_allocations
bcachefs (loop2): dropping and reconstructing all alloc info
invalid btree id 251 (max 63), fix?
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/btree_cache.c:198:18
shift exponent 251 is too large for 64-bit type 'unsigned long long'
CPU: 0 UID: 0 PID: 3366 Comm: syz.2.16 Not tainted 6.11.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x3e/0xe0 lib/dump_stack.c:119
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x248/0x270 lib/ubsan.c:468
 __btree_node_pinned+0x105/0x110 fs/bcachefs/btree_cache.c:198
 __bch2_btree_node_hash_insert+0x45c/0x5e0 fs/bcachefs/btree_cache.c:270
 bch2_btree_node_hash_insert+0x37/0x50 fs/bcachefs/btree_cache.c:287
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1743 [inline]
 bch2_btree_root_read+0x1bb/0x2b0 fs/bcachefs/btree_io.c:1771
 read_btree_roots+0x108/0x2e0 fs/bcachefs/recovery.c:523
 bch2_fs_recovery+0xfac/0x18e0 fs/bcachefs/recovery.c:851
 bch2_fs_start+0x1b9/0x270 fs/bcachefs/super.c:1037
 bch2_fs_get_tree+0x2b5/0x640 fs/bcachefs/fs.c:2069
 vfs_get_tree+0x24/0xb0 fs/super.c:1800
 do_new_mount+0x15a/0x3a0 fs/namespace.c:3472
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount+0x148/0x1b0 fs/namespace.c:3997
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x8d/0x190 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc805f874ca
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc806d24e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fc806d24ef0 RCX: 00007fc805f874ca
RDX: 0000000020000180 RSI: 0000000020000540 RDI: 00007fc806d24eb0
RBP: 0000000020000180 R08: 00007fc806d24ef0 R09: 0000000000800000
R10: 0000000000800000 R11: 0000000000000246 R12: 0000000020000540
R13: 00007fc806d24eb0 R14: 000000000000596a R15: 00000000200002c0
 </TASK>
---[ end trace ]---