rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (0 ticks this GP) idle=687c/1/0x4000000000000000 softirq=26328/26328 fqs=0 rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P767/1:b..l rcu: (detected by 0, t=10502 jiffies, g=42429, q=233 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7562 Comm: syz-executor.3 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__preempt_count_add arch/x86/include/asm/preempt.h:79 [inline] RIP: 0010:preempt_count_add+0x3d/0x190 kernel/sched/core.c:5869 Code: c1 e8 03 49 bf 00 00 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 ed 00 00 00 83 3d 9c 7c e5 12 00 75 07 65 8b 05 7b e6 9e 7e <65> 01 1d 74 e6 9e 7e 48 c7 c0 60 66 4a 94 48 c1 e8 03 42 0f b6 04 RSP: 0018:ffffc90000a08b40 EFLAGS: 00000046 RAX: 0000000080010002 RBX: 0000000000000001 RCX: ffffffff944a6603 RDX: 0000000000000001 RSI: ffffffff8baad360 RDI: 0000000000000001 RBP: ffffc90000a08bf0 R08: ffffffff8f860def R09: 1ffffffff1f0c1bd R10: dffffc0000000000 R11: fffffbfff1f0c1be R12: 0000000000000046 R13: 1ffff9200014116c R14: ffffffff946f04d0 R15: dffffc0000000000 FS: 000055555f3e3480(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003c80 CR3: 000000007d1c2000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:109 [inline] _raw_spin_lock_irqsave+0xba/0x120 kernel/locking/spinlock.c:162 debug_object_activate+0x16d/0x510 lib/debugobjects.c:708 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x30/0x3a0 kernel/time/hrtimer.c:1090 __run_hrtimer kernel/time/hrtimer.c:1709 [inline] __hrtimer_run_queues+0x6b5/0xd00 kernel/time/hrtimer.c:1756 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1818 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x107/0x3a0 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa1/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 Code: 9c 8f 44 24 20 42 80 3c 23 00 74 08 4c 89 f7 e8 fe 9e 7e f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 c3 94 ee f5 65 8b 05 d4 79 8d 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc90004dd7b80 EFLAGS: 00000206 RAX: 4212dec0e6a76600 RBX: 1ffff920009baf74 RCX: ffffffff944a6603 RDX: dffffc0000000000 RSI: ffffffff8baac1e0 RDI: 0000000000000001 RBP: ffffc90004dd7c10 R08: ffffffff8f860def R09: 1ffffffff1f0c1bd R10: dffffc0000000000 R11: fffffbfff1f0c1be R12: dffffc0000000000 R13: 1ffff920009baf70 R14: ffffc90004dd7ba0 R15: 0000000000000246 hrtimer_start_expires include/linux/hrtimer.h:289 [inline] hrtimer_sleeper_start_expires kernel/time/hrtimer.c:1972 [inline] do_nanosleep+0x158/0x600 kernel/time/hrtimer.c:2048 hrtimer_nanosleep+0x227/0x470 kernel/time/hrtimer.c:2104 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1396 [inline] __se_sys_clock_nanosleep+0x32b/0x3c0 kernel/time/posix-timers.c:1373 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75 RIP: 0033:0x7f6324ca9275 Code: 24 0c 89 3c 24 48 89 4c 24 18 e8 f6 b9 ff ff 4c 8b 54 24 18 48 8b 54 24 10 41 89 c0 8b 74 24 0c 8b 3c 24 b8 e6 00 00 00 0f 05 <44> 89 c7 48 89 04 24 e8 4f ba ff ff 48 8b 04 24 48 83 c4 28 f7 d8 RSP: 002b:00007ffef66fbb90 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000000000000214 RCX: 00007f6324ca9275 RDX: 00007ffef66fbbd0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffef66fbc5c R08: 0000000000000000 R09: 00007f63259f90b0 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000032 R13: 0000000000043719 R14: 0000000000043719 R15: 0000000000000000 task:kworker/u8:5 state:R running task stack:22032 pid:767 tgid:767 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1781/0x49d0 kernel/sched/core.c:6736 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:7058 irqentry_exit+0x5e/0x90 kernel/entry/common.c:348 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lock_acquire+0x25b/0x530 kernel/locking/lockdep.c:5758 Code: 2b 00 74 08 4c 89 f7 e8 b3 5a 83 00 f6 44 24 61 02 0f 85 8e 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc90003a779e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff9200074ef48 RCX: 0000000000000001 RDX: dffffc0000000000 RSI: ffffffff8baad360 RDI: ffffffff8bfdff00 RBP: ffffc90003a77b40 R08: ffffffff92cae507 R09: 1ffffffff2595ca0 R10: dffffc0000000000 R11: fffffbfff2595ca1 R12: 1ffff9200074ef44 R13: dffffc0000000000 R14: ffffc90003a77a40 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:298 [inline] rcu_read_lock include/linux/rcupdate.h:750 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0xec/0x610 net/batman-adv/network-coding.c:719 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa00/0x1770 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g42429 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=18287 rcu: rcu_preempt kthread starved for 10502 jiffies! g42429 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:25496 pid:16 tgid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5409 [inline] __schedule+0x1781/0x49d0 kernel/sched/core.c:6736 __schedule_loop kernel/sched/core.c:6813 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6828 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2572 rcu_gp_fqs_loop+0x2df/0x1370 kernel/rcu/tree.c:1663 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:1862 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243