rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3035/1:b..l rcu: (detected by 1, t=10503 jiffies, g=41705, q=277 ncpus=2) task:kworker/u8:9 state:R running task stack:19160 pid:3035 tgid:3035 ppid:2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 preempt_schedule_irq+0xfb/0x1c0 kernel/sched/core.c:6851 irqentry_exit+0x5e/0x90 kernel/entry/common.c:354 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:707 RIP: 0010:lock_acquire+0x264/0x550 kernel/locking/lockdep.c:5763 Code: 2b 00 74 08 4c 89 f7 e8 7a e1 87 00 f6 44 24 61 02 0f 85 85 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:ffffc90009f279e0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920013e4f48 RCX: d658003a3d15fc00 RDX: dffffc0000000000 RSI: ffffffff8beae6e0 RDI: ffffffff8c3fbb00 RBP: ffffc90009f27b40 R08: ffffffff93fa6847 R09: 1ffffffff27f4d08 R10: dffffc0000000000 R11: fffffbfff27f4d09 R12: 1ffff920013e4f44 R13: dffffc0000000000 R14: ffffc90009f27a40 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:326 [inline] rcu_read_lock include/linux/rcupdate.h:838 [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:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd10 kernel/workqueue.c:3389 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: rcu_preempt kthread timer wakeup didn't happen for 10500 jiffies! g41705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=23714 rcu: rcu_preempt kthread starved for 10501 jiffies! g41705 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26384 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5188 [inline] __schedule+0x17ae/0x4a10 kernel/sched/core.c:6529 __schedule_loop kernel/sched/core.c:6606 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6621 schedule_timeout+0x1be/0x310 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x2df/0x1330 kernel/rcu/tree.c:2034 rcu_gp_kthread+0xa7/0x3b0 kernel/rcu/tree.c:2236 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/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: Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 6294 Comm: syz.1.437 Not tainted 6.11.0-rc7-syzkaller-00021-g7c6a3a65ace7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 RIP: 0010:hlock_class kernel/locking/lockdep.c:239 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4772 [inline] RIP: 0010:__lock_acquire+0x4fb/0x2040 kernel/locking/lockdep.c:5092 Code: da 87 00 48 0f a3 1d d4 90 8a 12 73 27 48 69 c3 c8 00 00 00 48 8d 98 40 e7 96 93 48 ba 00 00 00 00 00 fc ff df 4c 8b 7c 24 10 <4c> 8b 74 24 20 e9 8e 00 00 00 48 c7 c0 c0 d9 0f 9a 48 c1 e8 03 48 RSP: 0018:ffffc90000007a70 EFLAGS: 00000002 RAX: 0000000000005398 RBX: ffffffff93973ad8 RCX: ffffffff816fd764 RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff93fa6848 RBP: 0000000000000005 R08: ffffffff93fa684f R09: 1ffffffff27f4d09 R10: dffffc0000000000 R11: fffffbfff27f4d0a R12: ffff88802e68bc00 R13: 000000000000006b R14: 00000000000c406b R15: ffff88802e68c728 FS: 00007f955c5dd6c0(0000) GS:ffff8880b8800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000e038 CR3: 000000007cf86000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5759 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 __run_hrtimer kernel/time/hrtimer.c:1693 [inline] __hrtimer_run_queues+0x670/0xd50 kernel/time/hrtimer.c:1753 hrtimer_interrupt+0x396/0x990 kernel/time/hrtimer.c:1815 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x110/0x3f0 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 5e 8b 3c f6 f6 44 24 21 02 75 52 41 f7 c7 00 02 00 00 74 01 fb bf 01 00 00 00 83 dc a7 f5 65 8b 05 64 b2 48 74 85 c0 74 43 48 c7 04 24 0e 36 RSP: 0018:ffffc9000348fa60 EFLAGS: 00000206 RAX: f05d817603ee6200 RBX: 1ffff92000691f50 RCX: ffffffff81703f9a RDX: dffffc0000000000 RSI: ffffffff8bead560 RDI: 0000000000000001 RBP: ffffc9000348faf0 R08: ffffffff93fa694f R09: 1ffffffff27f4d29 R10: dffffc0000000000 R11: fffffbfff27f4d2a R12: dffffc0000000000 R13: 1ffff92000691f4c R14: ffffc9000348fa80 R15: 0000000000000246 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] __wake_up_common_lock+0x18c/0x1e0 kernel/sched/wait.c:108 io_cqring_wake io_uring/io_uring.h:274 [inline] io_cq_unlock_post io_uring/io_uring.c:595 [inline] __io_cqring_overflow_flush+0x504/0x690 io_uring/io_uring.c:633 io_cqring_do_overflow_flush io_uring/io_uring.c:645 [inline] io_cqring_wait io_uring/io_uring.c:2486 [inline] __do_sys_io_uring_enter io_uring/io_uring.c:3255 [inline] __se_sys_io_uring_enter+0x1c36/0x2670 io_uring/io_uring.c:3147 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f955b77def9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f955c5dd038 EFLAGS: 00000246 ORIG_RAX: 00000000000001aa RAX: ffffffffffffffda RBX: 00007f955b935f80 RCX: 00007f955b77def9 RDX: 0000000000400000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f955b7f0b56 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f955b935f80 R15: 00007ffc8c273f38