rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P15605/1:b..l rcu: (detected by 0, t=10502 jiffies, g=61329, q=319 ncpus=2) task:syz-executor state:R running task stack:24096 pid:15605 tgid:15605 ppid:15598 task_flags:0x400140 flags:0x00000000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6943 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.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:1201 [inline] copy_pmd_range mm/memory.c:1262 [inline] copy_pud_range mm/memory.c:1299 [inline] copy_p4d_range mm/memory.c:1323 [inline] copy_page_range+0x1e7f/0x5690 mm/memory.c:1421 dup_mmap kernel/fork.c:748 [inline] dup_mm kernel/fork.c:1700 [inline] copy_mm kernel/fork.c:1752 [inline] copy_process+0x7ccb/0x8c50 kernel/fork.c:2403 kernel_clone+0xfd/0x960 kernel/fork.c:2815 __do_sys_clone+0xba/0x100 kernel/fork.c:2958 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: 0033:0x7f8a75583653 RSP: 002b:00007ffdd2009e98 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8a75583653 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: 0000555586ea37d0 R11: 0000000000000246 R12: 0000000000000000 R13: 00000000000927c0 R14: 00000000000c2199 R15: 00007ffdd200a030 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g61329 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=46576 rcu: rcu_preempt kthread starved for 10502 jiffies! g61329 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:26128 pid:17 tgid:17 ppid:2 task_flags:0x208040 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5377 [inline] __schedule+0xf43/0x5890 kernel/sched/core.c:6764 __schedule_loop kernel/sched/core.c:6841 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6856 schedule_timeout+0x124/0x280 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2024 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2226 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 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: 9188 Comm: kworker/u8:14 Not tainted 6.14.0-rc1-syzkaller-00034-g92514ef226f5 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Workqueue: bat_events batadv_tt_purge RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:154 [inline] RIP: 0010:lock_release+0x3d0/0x6f0 kernel/locking/lockdep.c:5875 Code: 20 f0 6c 8b e8 d1 bc bf 09 b8 ff ff ff ff 65 0f c1 05 7c eb 6b 7e 83 f8 01 0f 85 fe 01 00 00 9c 58 f6 c4 02 0f 85 e9 01 00 00 <48> f7 04 24 00 02 00 00 74 01 fb 48 b8 00 00 00 00 00 fc ff df 48 RSP: 0018:ffffc90000a18ca8 EFLAGS: 00000046 RAX: 0000000000000046 RBX: 1ffff92000143197 RCX: ffffc90000a18cf8 RDX: 1ffff110070aca6c RSI: ffffffff8b6cf020 RDI: ffffffff8bd34c80 RBP: b05ef340f351284c R08: 0000000000000000 R09: fffffbfff20c4502 R10: ffffffff90622817 R11: 0000000000000002 R12: 0000000000000002 R13: 0000000000000003 R14: ffff888038565368 R15: ffff888038564880 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffe7bfd6940 CR3: 0000000086464000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000000e DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline] _raw_spin_unlock+0x16/0x50 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:391 [inline] advance_sched+0x611/0xc60 net/sched/sch_taprio.c:981 __run_hrtimer kernel/time/hrtimer.c:1801 [inline] __hrtimer_run_queues+0x20a/0xae0 kernel/time/hrtimer.c:1865 hrtimer_interrupt+0x392/0x8e0 kernel/time/hrtimer.c:1927 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1038 [inline] __sysvec_apic_timer_interrupt+0x10f/0x400 arch/x86/kernel/apic/apic.c:1055 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1049 [inline] sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1049 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:write_comp_data+0x42/0x90 kernel/kcov.c:246 Code: a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 2c 16 00 00 85 c0 74 4f 8b 82 08 16 00 00 <83> f8 03 75 44 48 8b 82 10 16 00 00 8b 92 0c 16 00 00 48 8b 38 48 RSP: 0018:ffffc9000b1cfb30 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000400 RCX: ffffffff8b27adb0 RDX: ffff888038564880 RSI: 0000000000000046 RDI: 0000000000000004 RBP: ffff88805e5bbe80 R08: 0000000000000004 R09: 0000000000000046 R10: 0000000000000400 R11: 0000000000000002 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff88802f378228 R15: 0000000000000046 batadv_tt_global_purge net/batman-adv/translation-table.c:2226 [inline] batadv_tt_purge+0x280/0xb90 net/batman-adv/translation-table.c:3510 process_one_work+0x9c5/0x1ba0 kernel/workqueue.c:3236 process_scheduled_works kernel/workqueue.c:3317 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3398 kthread+0x3af/0x750 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244