BUG: MAX_LOCKDEP_CHAINS too low! turning off the locking correctness validator. CPU: 1 PID: 8661 Comm: syz.7.810 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/26/2026 Call trace: dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 dump_stack+0x1c/0x5c lib/dump_stack.c:113 add_chain_cache kernel/locking/lockdep.c:-1 [inline] lookup_chain_cache_add kernel/locking/lockdep.c:3772 [inline] validate_chain kernel/locking/lockdep.c:3793 [inline] __lock_acquire+0x1864/0x6800 kernel/locking/lockdep.c:5049 lock_acquire+0x20c/0x63c kernel/locking/lockdep.c:5662 _raw_spin_lock_nested+0x5c/0x78 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested kernel/sched/core.c:538 [inline] raw_spin_rq_lock kernel/sched/sched.h:1362 [inline] rq_lock kernel/sched/sched.h:1652 [inline] __schedule+0x2b8/0x1b0c kernel/sched/core.c:6478 preempt_schedule_irq+0x8c/0x1ac kernel/sched/core.c:6874 arm64_preempt_schedule_irq+0x44/0x54 arch/arm64/kernel/entry-common.c:265 __el1_irq arch/arm64/kernel/entry-common.c:474 [inline] el1_interrupt+0x3c/0x54 arch/arm64/kernel/entry-common.c:486 el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:491 el1h_64_irq+0x64/0x68 arch/arm64/kernel/entry.S:581 strcmp+0x2c/0xf0 lib/string.c:361 netdev_name_node_lookup_rcu net/core/dev.c:316 [inline] dev_get_by_name_rcu net/core/dev.c:781 [inline] dev_get_by_name+0x16c/0x30c net/core/dev.c:803 pppoe_connect+0x644/0xda8 drivers/net/ppp/pppoe.c:669 __sys_connect_file net/socket.c:2010 [inline] __sys_connect+0x28c/0x2b4 net/socket.c:2027 __do_sys_connect net/socket.c:2037 [inline] __se_sys_connect net/socket.c:2034 [inline] __arm64_sys_connect+0x7c/0x94 net/socket.c:2034 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585