BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! turning off the locking correctness validator. CPU: 0 UID: 0 PID: 7250 Comm: syz.0.302 Not tainted syzkaller #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 seqcount_lockdep_reader_access+0xbc/0x104 include/linux/seqlock.h:72 ktime_get+0x64/0x214 kernel/time/timekeeping.c:824 hrtimer_cb_get_time include/linux/hrtimer.h:164 [inline] start_dl_timer+0x1b8/0x428 kernel/sched/deadline.c:1105 update_curr_dl_se+0x25c/0x5f4 kernel/sched/deadline.c:1478 dl_server_update+0x84/0xb0 kernel/sched/deadline.c:1584 update_curr+0x338/0x600 kernel/sched/fair.c:1243 dequeue_entity+0x3c/0x1240 kernel/sched/fair.c:5384 dequeue_entities+0x194/0xf88 kernel/sched/fair.c:6984 dequeue_task_fair+0x1d0/0x3ec kernel/sched/fair.c:7080 dequeue_task+0x1f8/0x2bc kernel/sched/core.c:2122 block_task kernel/sched/core.c:2155 [inline] try_to_block_task kernel/sched/core.c:6585 [inline] __schedule+0x4e4/0x2864 kernel/sched/core.c:6896 __schedule_loop kernel/sched/core.c:7043 [inline] schedule+0xb4/0x230 kernel/sched/core.c:7058 blk_mq_freeze_queue_wait+0xe0/0x158 block/blk-mq.c:190 blk_mq_freeze_queue_nomemsave+0xe8/0x13c block/blk-mq.c:206 blk_mq_freeze_queue include/linux/blk-mq.h:934 [inline] elevator_change+0x158/0x3cc block/elevator.c:677 elevator_set_none+0x48/0xac block/elevator.c:781 blk_mq_elv_switch_none block/blk-mq.c:5023 [inline] __blk_mq_update_nr_hw_queues block/blk-mq.c:5066 [inline] blk_mq_update_nr_hw_queues+0x4c8/0x15f4 block/blk-mq.c:5124 nbd_start_device+0x158/0xa48 drivers/block/nbd.c:1478 nbd_genl_connect+0xf88/0x158c drivers/block/nbd.c:2228 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+0x5c/0x254 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:763 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596 nbd285: detected capacity change from 0 to 32