rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P11155/1:b..l rcu: (detected by 0, t=10505 jiffies, g=119097, q=433 ncpus=2) task:kworker/u8:16 state:R running task stack:18200 pid:11155 tgid:11155 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7078 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5853 Code: 2b 00 74 08 4c 89 f7 e8 4a 81 8c 00 f6 44 24 61 02 0f 85 85 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc900042ef980 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200085df3c RCX: ffff888081e6e4d8 RDX: dffffc0000000000 RSI: ffffffff8c0aea80 RDI: ffffffff8c6076a0 RBP: ffffc900042efad0 R08: ffffffff942e9887 R09: 1ffffffff285d310 R10: dffffc0000000000 R11: fffffbfff285d311 R12: 1ffff9200085df38 R13: dffffc0000000000 R14: ffffc900042ef9e0 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] batadv_nc_process_nc_paths+0xd6/0x3a0 net/batman-adv/network-coding.c:687 batadv_nc_worker+0x52c/0x610 net/batman-adv/network-coding.c:735 process_one_work kernel/workqueue.c:3229 [inline] process_scheduled_works+0xa63/0x1850 kernel/workqueue.c:3310 worker_thread+0x870/0xd30 kernel/workqueue.c:3391 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread timer wakeup didn't happen for 10500 jiffies! g119097 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=141366 rcu: rcu_preempt kthread starved for 10501 jiffies! g119097 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 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:I stack:25976 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0x17fb/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0x15a/0x290 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2045 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2247 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 27648 Comm: syz.0.4768 Not tainted 6.12.0-syzkaller-09435-g2c22dc1ee3a1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:advance_sched+0x287/0xca0 net/sched/sch_taprio.c:941 Code: 89 df e8 9c 86 31 f8 4c 8b 2b 48 8b 04 24 48 8d a8 40 01 00 00 48 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 <74> 08 48 89 ef e8 6f 86 31 f8 48 8b 6d 00 4c 89 ef 48 89 ee e8 b0 RSP: 0018:ffffc90000a18c70 EFLAGS: 00000046 RAX: 1ffff11008b5e828 RBX: ffff888045af5d50 RCX: dffffc0000000000 RDX: 0000000000010000 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffff888045af4140 R08: ffffffff89cc12ad R09: fffff5200014317c R10: dffffc0000000000 R11: fffff5200014317c R12: 0000000000000000 R13: 181009e47c000000 R14: ffff88807b02a330 R15: ffff888045af5c00 FS: 00007f48db6906c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 0000000032464000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1739 [inline] __hrtimer_run_queues+0x59b/0xd50 kernel/time/hrtimer.c:1803 hrtimer_interrupt+0x403/0xa40 kernel/time/hrtimer.c:1865 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x110/0x420 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:finish_task_switch+0x1ea/0x870 kernel/sched/core.c:5243 Code: c9 50 e8 79 07 0c 00 48 83 c4 08 4c 89 f7 e8 9d 39 00 00 e9 de 04 00 00 4c 89 f7 e8 30 32 6e 0a e8 3b 96 38 00 fb 48 8b 5d c0 <48> 8d bb f8 15 00 00 48 89 f8 48 c1 e8 03 49 be 00 00 00 00 00 fc RSP: 0018:ffffc9000df4f1a8 EFLAGS: 00000286 RAX: 010d43dda98bed00 RBX: ffff88802c40da00 RCX: ffffffff9a3f0903 RDX: dffffc0000000000 RSI: ffffffff8c0ad8a0 RDI: ffffffff8c6076a0 RBP: ffffc9000df4f1f0 R08: ffffffff901d0c37 R09: 1ffffffff203a186 R10: dffffc0000000000 R11: fffffbfff203a187 R12: 1ffff110170e7eac R13: dffffc0000000000 R14: ffff8880b863e740 R15: ffff8880b873f560 context_switch kernel/sched/core.c:5372 [inline] __schedule+0x1803/0x4be0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6848 schedule_timeout+0xb0/0x290 kernel/time/sleep_timeout.c:75 unix_wait_for_peer+0x250/0x340 net/unix/af_unix.c:1529 unix_dgram_sendmsg+0x127f/0x1f80 net/unix/af_unix.c:2131 sock_sendmsg_nosec net/socket.c:711 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:726 ____sys_sendmsg+0x52a/0x7e0 net/socket.c:2583 ___sys_sendmsg net/socket.c:2637 [inline] __sys_sendmmsg+0x36a/0x720 net/socket.c:2726 __do_sys_sendmmsg net/socket.c:2753 [inline] __se_sys_sendmmsg net/socket.c:2750 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2750 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f48da97e819 Code: 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 01 48 RSP: 002b:00007f48db690038 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007f48dab35fa0 RCX: 00007f48da97e819 RDX: 0000000000000651 RSI: 0000000020000000 RDI: 0000000000000005 RBP: 00007f48da9f175e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f48dab35fa0 R15: 00007ffced98d248