BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low! turning off the locking correctness validator. CPU: 0 UID: 0 PID: 6307 Comm: syz.0.687 Not tainted syzkaller #0 PREEMPT Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/02/2026 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+0xfdc/0x2ebc kernel/locking/lockdep.c:5237 lock_acquire+0x140/0x364 kernel/locking/lockdep.c:5868 _raw_spin_lock_nested+0x50/0x6c kernel/locking/spinlock.c:382 raw_spin_rq_lock_nested+0x2c/0x44 kernel/sched/core.c:652 raw_spin_rq_lock kernel/sched/sched.h:1624 [inline] rq_lock kernel/sched/sched.h:1968 [inline] __schedule+0x394/0x2db8 kernel/sched/core.c:7064 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0x13c/0x20c kernel/sched/core.c:7283 blk_mq_freeze_queue_wait+0xe0/0x160 block/blk-mq.c:191 blk_mq_freeze_queue_nomemsave+0x28/0x38 block/blk-mq.c:207 blk_mq_freeze_queue include/linux/blk-mq.h:956 [inline] queue_limits_commit_update_frozen+0x64/0xd8 block/blk-settings.c:590 nbd_set_size+0x344/0x54c drivers/block/nbd.c:374 nbd_start_device+0x860/0xa44 drivers/block/nbd.c:1540 nbd_genl_connect+0xffc/0x15d4 drivers/block/nbd.c:2239 genl_family_rcv_msg_doit+0x1e4/0x2d4 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x43c/0x620 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x238/0x414 net/netlink/af_netlink.c:2555 genl_rcv+0x38/0x50 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x600/0x7f8 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x648/0x948 net/netlink/af_netlink.c:1899 sock_sendmsg_nosec net/socket.c:787 [inline] __sock_sendmsg+0xc8/0x138 net/socket.c:802 ____sys_sendmsg+0x3d0/0x6c8 net/socket.c:2698 ___sys_sendmsg+0x198/0x224 net/socket.c:2752 __sys_sendmsg+0x160/0x214 net/socket.c:2784 __do_sys_sendmsg net/socket.c:2789 [inline] __se_sys_sendmsg net/socket.c:2787 [inline] __arm64_sys_sendmsg+0x80/0x94 net/socket.c:2787 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594