rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P8/1:b..l (detected by 0, t=10502 jiffies, g=343561, q=57) task:kworker/u4:0 state:R running task stack:23680 pid: 8 ppid: 2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:4995 [inline] __schedule+0xa94/0x4910 kernel/sched/core.c:6304 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6719 irqentry_exit+0x31/0x80 kernel/entry/common.c:425 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__sanitizer_cov_trace_pc+0x5c/0x60 kernel/kcov.c:210 Code: 82 80 15 00 00 83 f8 02 75 20 48 8b 8a 88 15 00 00 8b 92 84 15 00 00 48 8b 01 48 83 c0 01 48 39 c2 76 07 48 89 34 c1 48 89 01 0f 1f 00 41 55 41 54 49 89 fc 55 48 bd eb 83 b5 80 46 86 c8 61 RSP: 0018:ffffc90000eefc90 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880332e49a0 RCX: 0000000000000000 RDX: ffff888011c40200 RSI: ffffffff88e768dc RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff88e768cd R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000134 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:409 [inline] batadv_nc_worker+0x14c/0xfa0 net/batman-adv/network-coding.c:719 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307 worker_thread+0x657/0x1110 kernel/workqueue.c:2454 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g343561 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=1 timer-softirq=174929 rcu: rcu_preempt kthread starved for 10502 jiffies! g343561 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:28880 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4995 [inline] __schedule+0xa94/0x4910 kernel/sched/core.c:6304 schedule+0xd2/0x260 kernel/sched/core.c:6377 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1963 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136 kthread+0x2e9/0x3a0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: Stack dump where RCU GP kthread last ran: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 30459 Comm: syz-executor.3 Not tainted 5.17.0-rc7-syzkaller-00227-g68453767131a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:rcu_is_watching+0x0/0xb0 kernel/rcu/tree.c:1124 Code: 9c 5b 00 e9 2c ff ff ff 66 90 48 c7 c7 00 c0 ad 89 e8 f4 e2 e8 07 65 8a 05 99 6d a0 7e 0f be c0 c3 66 0f 1f 84 00 00 00 00 00 <55> 53 65 ff 05 47 30 9f 7e e8 b2 e2 e8 07 48 c7 c3 d0 ac 03 00 83 RSP: 0000:ffffc90002c5fd70 EFLAGS: 00000002 RAX: 0000000000000001 RBX: ffff88801a3ccb40 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff81674d6c RDI: 0000000000000003 RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff8167459d R11: 0000000000000000 R12: 0000000000000001 R13: ffff8880b9d2a700 R14: ffff8880b9d2a600 R15: 0000000000000001 FS: 00007feeae3b1700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feeae3b0fc8 CR3: 000000007cc97000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 000000000000003b DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: rcu_read_lock_held_common kernel/rcu/update.c:108 [inline] rcu_read_lock_sched_held+0x1c/0x70 kernel/rcu/update.c:123 trace_hrtimer_expire_exit include/trace/events/timer.h:279 [inline] __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0xa2e/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline] __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103 sysvec_apic_timer_interrupt+0x40/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0033:0x7feeaf9ee940 Code: 06 00 00 ff ff ff ff f0 64 83 0c 25 08 03 00 00 10 64 48 8b 3c 25 00 03 00 00 e8 5b 18 00 00 f4 66 2e 0f 1f 84 00 00 00 00 00 c7 02 00 00 00 75 27 64 8b 04 25 08 03 00 00 41 89 c3 41 83 e3 RSP: 002b:00007feeae3b0ef8 EFLAGS: 00000207 RAX: 0000000000000060 RBX: 00007feeafa859c8 RCX: 00007feeaf9ef017 RDX: 0000000000000060 RSI: 0000000020010800 RDI: 0000000000000000 RBP: 0000000000000031 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000008000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000003 R14: 0000000020000260 R15: 0000000000000004 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 80 15 00 00 83 f8 02 adcb $0x2,-0x77d0000(%rip) # 0xf8830007 7: 75 20 jne 0x29 9: 48 8b 8a 88 15 00 00 mov 0x1588(%rdx),%rcx 10: 8b 92 84 15 00 00 mov 0x1584(%rdx),%edx 16: 48 8b 01 mov (%rcx),%rax 19: 48 83 c0 01 add $0x1,%rax 1d: 48 39 c2 cmp %rax,%rdx 20: 76 07 jbe 0x29 22: 48 89 34 c1 mov %rsi,(%rcx,%rax,8) 26: 48 89 01 mov %rax,(%rcx) * 29: c3 retq <-- trapping instruction 2a: 0f 1f 00 nopl (%rax) 2d: 41 55 push %r13 2f: 41 54 push %r12 31: 49 89 fc mov %rdi,%r12 34: 55 push %rbp 35: 48 bd eb 83 b5 80 46 movabs $0x61c8864680b583eb,%rbp 3c: 86 c8 61