running recovery passes: check_allocations,check_extents_to_backpointers,check_inodes
bcachefs (loop0): invalid btree id 251 (max 63), fix?
bcachefs (loop0): dropping and reconstructing all alloc info
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/bcachefs/btree_cache.c:218:18
shift exponent 251 is too large for 64-bit type 'unsigned long long'
CPU: 0 UID: 0 PID: 5616 Comm: syz.0.16 Not tainted 6.15.0-rc1-syzkaller-g0af2f6be1b42 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 ubsan_epilogue lib/ubsan.c:231 [inline]
 __ubsan_handle_shift_out_of_bounds+0x3c8/0x420 lib/ubsan.c:492
 __btree_node_pinned fs/bcachefs/btree_cache.c:218 [inline]
 __bch2_btree_node_hash_insert+0x1b32/0x1ba0 fs/bcachefs/btree_cache.c:294
 bch2_btree_node_hash_insert+0x7e/0xc0 fs/bcachefs/btree_cache.c:309
 __bch2_btree_root_read fs/bcachefs/btree_io.c:1791 [inline]
 bch2_btree_root_read+0x605/0x7e0 fs/bcachefs/btree_io.c:1819
 read_btree_roots+0x3d7/0xa80 fs/bcachefs/recovery.c:581
 bch2_fs_recovery+0x28e4/0x3e20 fs/bcachefs/recovery.c:928
 bch2_fs_start+0x310/0x620 fs/bcachefs/super.c:1069
 bch2_fs_get_tree+0x113e/0x18f0 fs/bcachefs/fs.c:2253
 vfs_get_tree+0x90/0x2b0 fs/super.c:1759
 do_new_mount+0x2cf/0xb70 fs/namespace.c:3879
 do_mount fs/namespace.c:4219 [inline]
 __do_sys_mount fs/namespace.c:4430 [inline]
 __se_sys_mount+0x38c/0x400 fs/namespace.c:4407
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f791d5874ca
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:00007f791e3ece68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f791e3ecef0 RCX: 00007f791d5874ca
RDX: 0000000020000180 RSI: 0000000020000540 RDI: 00007f791e3eceb0
RBP: 0000000020000180 R08: 00007f791e3ecef0 R09: 0000000000800000
R10: 0000000000800000 R11: 0000000000000246 R12: 0000000020000540
R13: 00007f791e3eceb0 R14: 000000000000596a R15: 00000000200002c0
 </TASK>
---[ end trace ]---