rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=b75c/1/0x4000000000000000 softirq=5558/5559 fqs=1 rcu: (detected by 0, t=10506 jiffies, g=5001, q=113 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 3853 Comm: kworker/u4:8 Not tainted 6.8.0-rc1-syzkaller-00037-g443b349019f2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: bat_events batadv_nc_worker RIP: 0010:lock_is_held include/linux/lockdep.h:231 [inline] RIP: 0010:advance_sched+0x80b/0xc60 net/sched/sch_taprio.c:936 Code: 20 61 ef 8b be aa 03 00 00 48 c7 c7 80 60 ef 8b c6 05 27 5b 76 06 01 e8 73 4f b9 f8 e9 37 f9 ff ff e8 b9 91 d9 f8 49 8d 7e c0 ff ff ff ff e8 ab 73 df 01 31 ff 89 c3 89 c6 e8 10 8d d9 f8 85 RSP: 0018:ffffc900001f0d90 EFLAGS: 00000046 RAX: 0000000080010202 RBX: 0000000000000001 RCX: ffffffff88ae8988 RDX: ffff88802cd19dc0 RSI: ffffffff88ae90a7 RDI: ffff888023515300 RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000003 R12: ffff8880b992bac0 R13: 0000000000000000 R14: ffff888023515340 R15: ffffffff88ae88a0 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000600 CR3: 0000000027f87000 CR4: 0000000000350ef0 Call Trace: __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x203/0xc20 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1065 [inline] __sysvec_apic_timer_interrupt+0x105/0x400 arch/x86/kernel/apic/apic.c:1082 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1076 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:649 RIP: 0010:lock_acquire+0x1ef/0x520 kernel/locking/lockdep.c:5722 Code: c1 05 dd 04 9a 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 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:ffffc9000bd17a40 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff920017a2f4a RCX: ffffffff8167952e RDX: 0000000000000001 RSI: ffffffff8accb180 RDI: ffffffff8b2fd380 RBP: 0000000000000200 R08: 0000000000000000 R09: fffffbfff242ac01 R10: ffffffff9215600f R11: 0000000000000002 R12: 0000000000000001 R13: 0000000000000000 R14: ffff888077951b18 R15: 0000000000000000 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline] _raw_spin_lock_bh+0x33/0x40 kernel/locking/spinlock.c:178 spin_lock_bh include/linux/spinlock.h:356 [inline] batadv_nc_purge_paths+0xd3/0x3c0 net/batman-adv/network-coding.c:442 batadv_nc_worker+0x97a/0x10e0 net/batman-adv/network-coding.c:720 process_one_work+0x886/0x15d0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 1.028 msecs rcu: rcu_preempt kthread starved for 10500 jiffies! g5001 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:27984 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5400 [inline] __schedule+0xf12/0x5c00 kernel/sched/core.c:6727 __schedule_loop kernel/sched/core.c:6802 [inline] schedule+0xe9/0x270 kernel/sched/core.c:6817 schedule_timeout+0x137/0x290 kernel/time/timer.c:2183 rcu_gp_fqs_loop+0x1ec/0xb10 kernel/rcu/tree.c:1631 rcu_gp_kthread+0x24b/0x380 kernel/rcu/tree.c:1830 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 3878 Comm: kworker/u4:10 Not tainted 6.8.0-rc1-syzkaller-00037-g443b349019f2 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x4e9/0x1550 kernel/smp.c:855 Code: 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 7e c5 0b 00 f3 90 41 0f b6 04 24 <40> 38 c5 7c 08 84 c0 0f 85 24 0e 00 00 8b 43 08 31 ff 83 e0 01 41 RSP: 0018:ffffc9000be37930 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9942020 RCX: ffffffff817c5d08 RDX: ffff88802cd75940 RSI: ffffffff817c5ce2 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed1017328405 R13: 0000000000000001 R14: ffff8880b9942028 R15: ffff8880b983de80 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055575f124000 CR3: 000000000cf78000 CR4: 0000000000350ef0 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2087 [inline] text_poke_bp_batch+0x22b/0x750 arch/x86/kernel/alternative.c:2297 text_poke_flush arch/x86/kernel/alternative.c:2488 [inline] text_poke_flush arch/x86/kernel/alternative.c:2485 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2495 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:829 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:826 [inline] toggle_allocation_gate+0xf4/0x250 mm/kfence/core.c:818 process_one_work+0x886/0x15d0 kernel/workqueue.c:2633 process_scheduled_works kernel/workqueue.c:2706 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2787 kthread+0x2c6/0x3a0 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242