rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3646/1:b..l (detected by 1, t=10502 jiffies, g=7641, q=140) task:udevd state:R running task stack: 0 pid: 3646 ppid: 1 flags:0x00000004 Call trace: __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521 context_switch kernel/sched/core.c:5030 [inline] __schedule+0xe00/0x1c0c kernel/sched/core.c:6376 preempt_schedule_common+0x138/0x218 kernel/sched/core.c:6552 preempt_schedule+0x64/0x84 kernel/sched/core.c:6577 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline] _raw_spin_unlock_irqrestore+0x108/0x14c kernel/locking/spinlock.c:194 spin_unlock_irqrestore include/linux/spinlock.h:418 [inline] __wake_up_common_lock kernel/sched/wait.c:140 [inline] __wake_up_sync_key+0x11c/0x178 kernel/sched/wait.c:205 sock_def_readable+0x150/0x278 net/core/sock.c:3093 __netlink_sendskb net/netlink/af_netlink.c:1258 [inline] netlink_sendskb+0xa4/0x178 net/netlink/af_netlink.c:1264 netlink_unicast+0x2d8/0x89c net/netlink/af_netlink.c:1352 netlink_sendmsg+0x6e8/0x9cc net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x61c/0x920 net/socket.c:2436 ___sys_sendmsg+0x1d0/0x240 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg net/socket.c:2526 [inline] __arm64_sys_sendmsg+0x1a8/0x254 net/socket.c:2526 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 rcu: rcu_preempt kthread starved for 10505 jiffies! g7641 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 rcu: Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior. rcu: RCU grace-period kthread stack dump: task:rcu_preempt state:R running task stack: 0 pid: 15 ppid: 2 flags:0x00000008 Call trace: __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521 context_switch kernel/sched/core.c:5030 [inline] __schedule+0xe00/0x1c0c kernel/sched/core.c:6376 schedule+0x11c/0x1c8 kernel/sched/core.c:6459 schedule_timeout+0x180/0x2c8 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x25c/0x11f0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xc4/0x2a8 kernel/rcu/tree.c:2145 kthread+0x374/0x454 kernel/kthread.c:334 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 rcu: Stack dump where RCU GP kthread last ran: Task dump for CPU 0: task:syz-executor.3 state:R running task stack: 0 pid: 4658 ppid: 4334 flags:0x00000000 Call trace: __switch_to+0x2f4/0x558 arch/arm64/kernel/process.c:521 0xffff80001fb57eb0