rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5406/1:b..l (detected by 0, t=10502 jiffies, g=63841, q=648 ncpus=2) task:kworker/u4:12 state:R running task stack:22144 pid:5406 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5209 [inline] __schedule+0x8fc/0xda0 kernel/sched/core.c:6521 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6833 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x21e/0x400 kernel/locking/lockdep.c:5672 Code: 23 00 74 08 4c 89 f7 e8 80 a6 75 00 f6 44 24 61 02 0f 85 76 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 04 2c 00 00 00 00 43 c7 44 2c 09 00 00 00 00 43 c7 44 2c 11 RSP: 0018:ffffc900051a7a60 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff92000a34f58 RCX: ffff888023b0c4c8 RDX: dffffc0000000000 RSI: ffffffff8b0da320 RDI: ffffffff8b68fd40 RBP: ffffc900051a7bb8 R08: dffffc0000000000 R09: fffffbfff20e4c29 R10: fffffbfff20e4c29 R11: 1ffffffff20e4c28 R12: dffffc0000000000 R13: 1ffff92000a34f54 R14: ffffc900051a7ac0 R15: 0000000000000246 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:304 rcu_read_lock include/linux/rcupdate.h:738 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xc8/0x5b0 net/batman-adv/network-coding.c:719 process_one_work+0x81c/0xd10 kernel/workqueue.c:2289 worker_thread+0xb14/0x1330 kernel/workqueue.c:2436 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: rcu_preempt kthread starved for 10375 jiffies! g63841 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:26552 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5209 [inline] __schedule+0x8fc/0xda0 kernel/sched/core.c:6521 schedule+0xcb/0x190 kernel/sched/core.c:6597 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x309/0x1070 kernel/rcu/tree.c:1660 rcu_gp_kthread+0xa5/0x390 kernel/rcu/tree.c:1859 kthread+0x266/0x300 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 16029 Comm: syz-executor.5 Not tainted 6.1.0-rc6-syzkaller-00012-g4312098baf37 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 RIP: 0010:csd_lock_wait kernel/smp.c:413 [inline] RIP: 0010:smp_call_function_many_cond+0xe92/0x1420 kernel/smp.c:987 Code: 84 c0 75 74 45 8b 26 44 89 e6 83 e6 01 31 ff e8 e4 3d 0b 00 41 83 e4 01 75 0e e8 b9 39 0b 00 eb 4c 0f 1f 80 00 00 00 00 f3 90 <48> b8 00 00 00 00 00 fc ff df 0f b6 04 03 84 c0 75 10 41 f7 06 01 RSP: 0018:ffffc90008c779e0 EFLAGS: 00000246 RAX: ffffffff81815aa2 RBX: 1ffff11017328021 RCX: 0000000000040000 RDX: ffffc9000c4dc000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: ffffc90008c77b80 R08: ffffffff81815a6c R09: fffffbfff20e4c29 R10: fffffbfff20e4c29 R11: 1ffffffff20e4c28 R12: 0000000000000001 R13: 0000000000000001 R14: ffff8880b9940108 R15: ffff8880b983ae80 FS: 00007f2fb61cd700(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000200b1030 CR3: 000000002b2ef000 CR4: 00000000003506f0 Call Trace: on_each_cpu_cond_mask+0x3b/0x80 kernel/smp.c:1155 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:1311 [inline] text_poke_bp_batch+0x2b4/0x850 arch/x86/kernel/alternative.c:1502 text_poke_flush arch/x86/kernel/alternative.c:1670 [inline] text_poke_finish+0x16/0x30 arch/x86/kernel/alternative.c:1677 arch_jump_label_transform_apply+0x13/0x20 arch/x86/kernel/jump_label.c:146 static_key_enable_cpuslocked+0x129/0x250 kernel/jump_label.c:177 static_key_enable+0x16/0x20 kernel/jump_label.c:190 __sched_core_enable kernel/sched/core.c:376 [inline] sched_core_get+0xa6/0x1d0 kernel/sched/core.c:400 sched_core_alloc_cookie+0x70/0xa0 kernel/sched/core_sched.c:18 sched_core_share_pid+0x2d1/0x760 kernel/sched/core_sched.c:185 __do_sys_prctl+0x338/0x1270 kernel/sys.c:2623 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f2fb548c0d9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f2fb61cd168 EFLAGS: 00000246 ORIG_RAX: 000000000000009d RAX: ffffffffffffffda RBX: 00007f2fb55abf80 RCX: 00007f2fb548c0d9 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 000000000000003e RBP: 00007f2fb54e7ae9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffa0a5e39f R14: 00007f2fb61cd300 R15: 0000000000022000