syzbot

BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
turning off the locking correctness validator.
CPU: 0 UID: 0 PID: 8882 Comm: syz.0.733 Not tainted 6.17.0-rc1-syzkaller-g8f5ae30d69d7 #0 PREEMPT 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/30/2025
Call trace:
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:499 (C)
 __dump_stack+0x30/0x40 lib/dump_stack.c:94
 dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
 dump_stack+0x1c/0x28 lib/dump_stack.c:129
 add_chain_cache kernel/locking/lockdep.c:-1 [inline]
 lookup_chain_cache_add kernel/locking/lockdep.c:3855 [inline]
 validate_chain kernel/locking/lockdep.c:3876 [inline]
 __lock_acquire+0xf9c/0x30a4 kernel/locking/lockdep.c:5237
 lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5868
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
 percpu_ref_resurrect+0x34/0x110 lib/percpu-refcount.c:468
 __blk_mq_unfreeze_queue block/blk-mq.c:220 [inline]
 blk_mq_unfreeze_queue_nomemrestore+0x90/0x25c block/blk-mq.c:231
 blk_mq_unfreeze_queue include/linux/blk-mq.h:940 [inline]
 elevator_change+0x278/0x3cc block/elevator.c:692
 elevator_set_default+0x138/0x21c block/elevator.c:766
 blk_register_queue+0x2c4/0x348 block/blk-sysfs.c:905
 __add_disk+0x560/0xb90 block/genhd.c:528
 add_disk_fwnode+0xdc/0x438 block/genhd.c:597
 device_add_disk+0x38/0x4c block/genhd.c:627
 add_disk include/linux/blkdev.h:773 [inline]
 nbd_dev_add+0x560/0x820 drivers/block/nbd.c:1973
 nbd_genl_connect+0x7a0/0x158c drivers/block/nbd.c:2114
 genl_family_rcv_msg_doit+0x1d8/0x2bc net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x450/0x624 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x220/0x3fc net/netlink/af_netlink.c:2552
 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline]
 netlink_unicast+0x694/0x8c4 net/netlink/af_netlink.c:1346
 netlink_sendmsg+0x648/0x930 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg net/socket.c:729 [inline]
 ____sys_sendmsg+0x490/0x7b8 net/socket.c:2614
 ___sys_sendmsg+0x204/0x278 net/socket.c:2668
 __sys_sendmsg net/socket.c:2700 [inline]
 __do_sys_sendmsg net/socket.c:2705 [inline]
 __se_sys_sendmsg net/socket.c:2703 [inline]
 __arm64_sys_sendmsg+0x184/0x238 net/socket.c:2703
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596