rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P12047/1:b..l P139/1:b..l rcu: (detected by 0, t=10502 jiffies, g=83941, q=418 ncpus=2) task:kworker/u8:5 state:R running task stack:21472 pid:139 tgid:139 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6746 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7068 irqentry_exit+0x36/0x90 kernel/entry/common.c:354 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x1f2/0x560 kernel/locking/lockdep.c:5722 Code: c1 05 ca 99 96 7e 83 f8 01 0f 85 ea 02 00 00 9c 58 f6 c4 02 0f 85 d5 02 00 00 48 85 ed 74 01 fb 48 b8 00 00 00 00 00 fc ff df <48> 01 c3 48 c7 03 00 00 00 00 48 c7 43 08 00 00 00 00 48 8b 84 24 RSP: 0018:ffffc90002d27a78 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920005a4f51 RCX: 00000000da62243c RDX: 0000000000000001 RSI: ffffffff8b0cb100 RDI: ffffffff8b6f56e0 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff27bba30 R10: ffffffff93ddd187 R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff8d7b0e20 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:329 [inline] rcu_read_lock include/linux/rcupdate.h:781 [inline] batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:754 [inline] batadv_iv_ogm_schedule_buff+0x5ac/0x1500 net/batman-adv/bat_iv_ogm.c:825 batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:868 [inline] batadv_iv_ogm_schedule net/batman-adv/bat_iv_ogm.c:861 [inline] batadv_iv_send_outstanding_bat_ogm_packet+0x31e/0x8d0 net/batman-adv/bat_iv_ogm.c:1712 process_one_work+0x9a9/0x1ac0 kernel/workqueue.c:3267 process_scheduled_works kernel/workqueue.c:3348 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3429 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 task:syz-executor.1 state:R running task stack:23968 pid:12047 tgid:12047 ppid:12030 flags:0x00000002 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6746 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6925 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:12 __raw_spin_unlock include/linux/spinlock_api_smp.h:143 [inline] _raw_spin_unlock+0x3e/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] copy_pte_range mm/memory.c:1177 [inline] copy_pmd_range mm/memory.c:1238 [inline] copy_pud_range mm/memory.c:1275 [inline] copy_p4d_range mm/memory.c:1299 [inline] copy_page_range+0x1308/0x47b0 mm/memory.c:1397 dup_mmap kernel/fork.c:751 [inline] dup_mm kernel/fork.c:1688 [inline] copy_mm kernel/fork.c:1737 [inline] copy_process+0x8098/0x9090 kernel/fork.c:2390 kernel_clone+0xfd/0x980 kernel/fork.c:2797 __do_sys_clone+0xba/0x100 kernel/fork.c:2940 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f8904a7acd3 RSP: 002b:00007fff3b2c57c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8904a7acd3 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000 R10: 0000555580bea750 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000001 rcu: rcu_preempt kthread starved for 10268 jiffies! g83941 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:27664 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6746 __schedule_loop kernel/sched/core.c:6823 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6838 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2582 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:1663 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:1862 kthread+0x2c1/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 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: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.9.0-rc6-syzkaller-00290-gb9158815de52 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:native_irq_disable arch/x86/include/asm/irqflags.h:37 [inline] RIP: 0010:arch_local_irq_disable arch/x86/include/asm/irqflags.h:72 [inline] RIP: 0010:acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:113 Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 65 48 8b 05 48 0e 28 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d b8 05 9f 00 fb f4 c3 cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 0018:ffffffff8d407d70 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8adbac59 RDX: 0000000000000001 RSI: ffff8880196f3000 RDI: ffff8880196f3064 RBP: ffff8880196f3064 R08: 0000000000000001 R09: ffffed1017286fdd R10: ffff8880b9437eeb R11: 0000000000000000 R12: ffff88801776f800 R13: ffffffff8e33a300 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9fd9e54d58 CR3: 000000007a6c8000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0xc5/0x160 drivers/acpi/processor_idle.c:707 cpuidle_enter_state+0x85/0x500 drivers/cpuidle/cpuidle.c:267 cpuidle_enter+0x4e/0xa0 drivers/cpuidle/cpuidle.c:388 cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x313/0x3f0 kernel/sched/idle.c:332 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:430 rest_init+0x16b/0x2b0 init/main.c:739 start_kernel+0x3a3/0x490 init/main.c:1081 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488 common_startup_64+0x13e/0x148