rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P22007/1:b..l P16002/1:b..l rcu: (detected by 1, t=10502 jiffies, g=263117, q=642 ncpus=2) task:kworker/u8:14 state:R running task stack:21696 pid:16002 tgid:16002 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7067 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:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:200 Code: be b0 01 00 00 e8 a0 ff ff ff 31 c0 c3 cc cc cc cc 66 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 65 48 8b 15 e4 f4 75 7e 65 8b 05 e5 f4 75 7e a9 00 01 RSP: 0018:ffffc90003367b58 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffff8880780c0c40 RCX: ffffffff8aa728bb RDX: ffff88805e139e00 RSI: 0000000000000000 RDI: 0000000000000001 RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: dffffc0000000000 R13: ffff88804a1a0ca0 R14: 0000000000000188 R15: ffff88801f5c9740 batadv_iv_ogm_slide_own_bcast_window net/batman-adv/bat_iv_ogm.c:755 [inline] batadv_iv_ogm_schedule_buff+0x5ca/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+0x9c5/0x1b40 kernel/workqueue.c:3248 process_scheduled_works kernel/workqueue.c:3329 [inline] worker_thread+0x6c8/0xf30 kernel/workqueue.c:3409 kthread+0x2c1/0x3a0 kernel/kthread.c:389 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.2.5051 state:R running task stack:26128 pid:22007 tgid:22001 ppid:21502 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6924 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x61/0x80 kernel/locking/spinlock.c:194 unix_write_space+0x20a/0x510 net/unix/af_unix.c:541 sock_wfree+0x252/0x850 net/core/sock.c:2482 unix_destruct_scm+0x138/0x190 net/unix/af_unix.c:1833 skb_release_head_state+0xa3/0x2b0 net/core/skbuff.c:1160 skb_release_all net/core/skbuff.c:1171 [inline] __kfree_skb net/core/skbuff.c:1187 [inline] consume_skb net/core/skbuff.c:1409 [inline] consume_skb+0x92/0x170 net/core/skbuff.c:1403 unix_stream_read_generic+0x21f6/0x28f0 net/unix/af_unix.c:2858 unix_stream_recvmsg+0x192/0x1c0 net/unix/af_unix.c:2937 sock_recvmsg_nosec net/socket.c:1046 [inline] sock_recvmsg+0x1f6/0x250 net/socket.c:1068 ____sys_recvmsg+0x21f/0x6b0 net/socket.c:2804 ___sys_recvmsg+0x115/0x1a0 net/socket.c:2846 do_recvmmsg+0x2ba/0x750 net/socket.c:2940 __sys_recvmmsg net/socket.c:3019 [inline] __do_sys_recvmmsg net/socket.c:3042 [inline] __se_sys_recvmmsg net/socket.c:3035 [inline] __x64_sys_recvmmsg+0x239/0x290 net/socket.c:3035 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7ff7b5775bd9 RSP: 002b:00007ff7b51bd048 EFLAGS: 00000246 ORIG_RAX: 000000000000012b RAX: ffffffffffffffda RBX: 00007ff7b5904110 RCX: 00007ff7b5775bd9 RDX: 040000000000013c RSI: 00000000200034c0 RDI: 0000000000000008 RBP: 00007ff7b57e4a98 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007ff7b5904110 R15: 00007ffed8ebdd18 rcu: rcu_preempt kthread starved for 10527 jiffies! g263117 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:26352 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 kthread+0x2c1/0x3a0 kernel/kthread.c:389 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: 1 PID: 0 Comm: swapper/1 Not tainted 6.10.0-rc6-syzkaller-00061-ge9d22f7a6655 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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 88 63 1c 75 48 8b 00 a8 08 75 0c 66 90 0f 00 2d 58 be b3 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: 0000:ffffc900001a7d58 EFLAGS: 00000246 RAX: 0000000000004000 RBX: 0000000000000001 RCX: ffffffff8ae75899 RDX: 0000000000000001 RSI: ffff8880196d5800 RDI: ffff8880196d5864 RBP: ffff8880196d5864 R08: 0000000000000001 R09: ffffed1017266fdd R10: ffff8880b9337eeb R11: 0000000000000000 R12: ffff88801bb9a800 R13: ffffffff8e742500 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c3484bf CR3: 000000005af9a000 CR4: 00000000003526f0 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 start_secondary+0x220/0x2b0 arch/x86/kernel/smpboot.c:313 common_startup_64+0x13e/0x148