rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5319/1:b..l (detected by 1, t=10502 jiffies, g=25329, q=172) task:kworker/u4:8 state:R running task stack:24184 pid: 5319 ppid: 2 flags:0x00004000 Workqueue: bat_events batadv_nc_worker Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4900 kernel/sched/core.c:6253 preempt_schedule_irq+0x4e/0x90 kernel/sched/core.c:6668 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:lock_acquire+0x1ef/0x510 kernel/locking/lockdep.c:5605 Code: c6 a5 7e 83 f8 01 0f 85 b4 02 00 00 9c 58 f6 c4 02 0f 85 9f 02 00 00 48 83 7c 24 08 00 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:ffffc90002cdfba0 EFLAGS: 00000206 RAX: dffffc0000000000 RBX: 1ffff9200059bf76 RCX: 1df6d4b7f56e899c RDX: 1ffff1100dc51c2b RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8ff9ba07 R10: fffffbfff1ff3740 R11: 0000000000000000 R12: 0000000000000002 R13: 0000000000000000 R14: ffffffff8bb83da0 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:268 [inline] rcu_read_lock include/linux/rcupdate.h:688 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x12d/0xfa0 net/batman-adv/network-coding.c:719 process_one_work+0x9b2/0x1660 kernel/workqueue.c:2298 worker_thread+0x65d/0x1130 kernel/workqueue.c:2445 kthread+0x405/0x4f0 kernel/kthread.c:327 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g25329 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 rcu: Possible timer handling issue on cpu=0 timer-softirq=13278 rcu: rcu_preempt kthread starved for 10502 jiffies! g25329 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:28680 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4972 [inline] __schedule+0xa9a/0x4900 kernel/sched/core.c:6253 schedule+0xd2/0x260 kernel/sched/core.c:6326 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1955 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2128 kthread+0x405/0x4f0 kernel/kthread.c:327 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 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 3630 Comm: syz-executor.4 Not tainted 5.16.0-rc8-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:separate_irq_context kernel/locking/lockdep.c:4541 [inline] RIP: 0010:__lock_acquire+0x961/0x5470 kernel/locking/lockdep.c:5011 Code: 89 e2 48 c1 ea 03 80 3c 02 00 0f 85 c7 38 00 00 48 8b 14 24 49 89 1c 24 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 0f b6 04 02 <84> c0 74 08 3c 03 0f 8e 93 38 00 00 41 8b 85 58 0a 00 00 85 c0 74 RSP: 0018:ffffc90000007b08 EFLAGS: 00000806 RAX: 0000000000000000 RBX: 221e6d18987de8af RCX: 0000000000000002 RDX: 1ffff11003dab14b RSI: 0000000000000008 RDI: ffffffff8ff9ba00 RBP: ffff88801ed58ad2 R08: 0000000000000000 R09: ffffffff8ff9ba07 R10: fffffbfff1ff3740 R11: 0000000000000001 R12: ffff88801ed58ab0 R13: ffff88801ed58000 R14: ffff88801ed58a60 R15: 0000000000000000 FS: 00005555569cc400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f675c05f1b8 CR3: 0000000053223000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 debug_object_deactivate lib/debugobjects.c:735 [inline] debug_object_deactivate+0x101/0x300 lib/debugobjects.c:723 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate kernel/time/hrtimer.c:481 [inline] __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x3f8/0xe50 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+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:rcu_lockdep_current_cpu_online kernel/rcu/tree.c:1171 [inline] RIP: 0010:rcu_lockdep_current_cpu_online+0x9e/0x150 kernel/rcu/tree.c:1160 Code: 48 8d 7b 18 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 90 00 00 00 48 8d 7b 20 48 8b 6b 18 48 b8 00 00 00 00 00 fc ff df 48 89 fa <48> c1 ea 03 80 3c 02 00 75 7b 48 8d 7d 70 48 8b 5b 20 48 b8 00 00 RSP: 0018:ffffc9000289fbc0 EFLAGS: 00000246 RAX: dffffc0000000000 RBX: ffff8880b9c3a900 RCX: ffffffff815cb308 RDX: ffff8880b9c3a920 RSI: 0000000000000002 RDI: ffff8880b9c3a920 RBP: ffffffff8bb8cb00 R08: 0000000000000000 R09: ffffffff8d920ed7 R10: fffffbfff1b241da R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: ffffffff8bcca540 R15: 0000000000000000 rcu_read_lock_held_common kernel/rcu/update.c:112 [inline] rcu_read_lock_held_common kernel/rcu/update.c:102 [inline] rcu_read_lock_sched_held+0x25/0x70 kernel/rcu/update.c:123 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0x442/0x510 kernel/locking/lockdep.c:5608 fs_reclaim_acquire mm/page_alloc.c:4552 [inline] fs_reclaim_acquire+0xd2/0x160 mm/page_alloc.c:4543 might_alloc include/linux/sched/mm.h:227 [inline] slab_pre_alloc_hook mm/slab.h:492 [inline] slab_alloc_node mm/slub.c:3148 [inline] slab_alloc mm/slub.c:3242 [inline] kmem_cache_alloc+0x3e/0x3a0 mm/slub.c:3247 sk_prot_alloc+0x5f/0x290 net/core/sock.c:1915 sk_alloc+0x32/0xa80 net/core/sock.c:1974 inet6_create net/ipv6/af_inet6.c:184 [inline] inet6_create+0x36f/0x1030 net/ipv6/af_inet6.c:111 __sock_create+0x353/0x790 net/socket.c:1468 sock_create net/socket.c:1519 [inline] __sys_socket+0xef/0x200 net/socket.c:1561 __do_sys_socket net/socket.c:1570 [inline] __se_sys_socket net/socket.c:1568 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f675bf81517 Code: f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 b8 29 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc8d16c348 EFLAGS: 00000206 ORIG_RAX: 0000000000000029 RAX: ffffffffffffffda RBX: 0000000000000029 RCX: 00007f675bf81517 RDX: 0000000000000006 RSI: 0000000000000001 RDI: 000000000000000a RBP: 00007ffc8d16c370 R08: 0000000000000000 R09: ffffff0000000000 R10: 0000000000000010 R11: 0000000000000206 R12: 0000000000000032 R13: 000000000003cafc R14: 0000000000000002 R15: 00007f675c060b60 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: a5 movsl %ds:(%rsi),%es:(%rdi) 1: 7e 83 jle 0xffffff86 3: f8 clc 4: 01 0f add %ecx,(%rdi) 6: 85 b4 02 00 00 9c 58 test %esi,0x589c0000(%rdx,%rax,1) d: f6 c4 02 test $0x2,%ah 10: 0f 85 9f 02 00 00 jne 0x2b5 16: 48 83 7c 24 08 00 cmpq $0x0,0x8(%rsp) 1c: 74 01 je 0x1f 1e: fb sti 1f: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 26: fc ff df * 29: 48 01 c3 add %rax,%rbx <-- trapping instruction 2c: 48 c7 03 00 00 00 00 movq $0x0,(%rbx) 33: 48 c7 43 08 00 00 00 movq $0x0,0x8(%rbx) 3a: 00 3b: 48 rex.W 3c: 8b .byte 0x8b 3d: 84 .byte 0x84 3e: 24 .byte 0x24