rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4900/1:b..l (detected by 1, t=10503 jiffies, g=12761, q=666) task:syz-executor state:R running task stack:20792 pid: 4900 ppid: 4885 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 vprintk_emit+0x146/0x150 kernel/printk/printk.c:2275 _printk+0xd1/0x120 kernel/printk/printk.c:2299 batadv_check_known_mac_addr+0x296/0x3d0 net/batman-adv/hard-interface.c:524 batadv_hard_if_event+0x300/0x17a0 net/batman-adv/hard-interface.c:986 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2018 [inline] call_netdevice_notifiers_extack net/core/dev.c:2030 [inline] call_netdevice_notifiers net/core/dev.c:2044 [inline] dev_set_mac_address+0x325/0x470 net/core/dev.c:9082 dev_set_mac_address_user+0x2d/0x50 net/core/dev.c:9096 do_setlink+0x7f0/0x3d80 net/core/rtnetlink.c:2731 __rtnl_newlink net/core/rtnetlink.c:3447 [inline] rtnl_newlink+0x17d6/0x2070 net/core/rtnetlink.c:3569 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5647 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2489 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1337 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x564/0x720 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2071 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fdd363f7d4c RSP: 002b:00007ffe0d037f80 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fdd370c0620 RCX: 00007fdd363f7d4c RDX: 000000000000002c RSI: 00007fdd370c0670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffe0d037fd4 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007fdd370c0670 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10547 jiffies! g12761 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:27064 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 5172 Comm: syz.1.25 Not tainted 5.15.177-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:mark_lock+0x0/0x340 kernel/locking/lockdep.c:4552 Code: ff ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 73 ff ff ff 4c 89 ff e8 ae 30 67 00 e9 66 ff ff ff e8 14 02 dc 08 0f 1f 40 00 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 10 49 89 f7 48 89 3c 24 49 RSP: 0018:ffffc90000007b38 EFLAGS: 00000006 RAX: 00000000000e4045 RBX: ffff88807b288b18 RCX: ffffffff81633dd8 RDX: 0000000000000008 RSI: ffff88807b288b18 RDI: ffff88807b288000 RBP: ffff88807b288000 R08: dffffc0000000000 R09: fffffbfff2131822 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001 R13: ffff88807b288ae8 R14: 0000000000000000 R15: ffff88807b288b38 FS: 00007fc7914516c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002006b000 CR3: 000000005d1e6000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4512 [inline] __lock_acquire+0xc97/0x1ff0 kernel/locking/lockdep.c:4966 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 seqcount_lockdep_reader_access+0xf8/0x220 include/linux/seqlock.h:103 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get_update_offsets_now+0x89/0x420 kernel/time/timekeeping.c:2303 hrtimer_update_base kernel/time/hrtimer.c:631 [inline] hrtimer_interrupt+0x12f/0x980 kernel/time/hrtimer.c:1796 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x13b/0x4b0 arch/x86/kernel/apic/apic.c:1114 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: 31 61 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 0e 15 1a f7 48 89 df e8 66 69 1b f7 e8 b1 25 3e f7 fb bf 01 00 00 00 66 ae 0e f7 65 8b 05 77 91 b9 75 85 c0 74 02 5b c3 e8 44 ae b7 RSP: 0018:ffffc9000302fbc0 EFLAGS: 00000282 RAX: 3ff1e3467b1a6500 RBX: ffff88807d9d0940 RCX: ffffffff96a92f03 RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff81870420 R09: ffffed100fb3a129 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021 R13: dffffc0000000000 R14: ffff88807d9d0dd8 R15: ffff88807d9d0940 spin_unlock_irq include/linux/spinlock.h:413 [inline] get_signal+0x13ee/0x14e0 kernel/signal.c:2903 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fc7921cceb7 Code: ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 <0f> 05 48 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 RSP: 002b:00007fc7914510e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007fc792368f88 RCX: 00007fc7921cceb9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fc792368f88 RBP: 00007fc792368f80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc792368f8c R13: 0000000000000000 R14: 00007ffeaefc62f0 R15: 00007ffeaefc63d8 sched: RT throttling activated