rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): (detected by 0, t=10503 jiffies, g=333317, q=415) rcu: All QSes seen, last rcu_preempt kthread activity 10473 (4295244220-4295233747), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10474 jiffies! g333317 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R running task stack:28816 pid: 14 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:4683 [inline] __schedule+0x934/0x2710 kernel/sched/core.c:5940 schedule+0xd3/0x270 kernel/sched/core.c:6019 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1892 rcu_gp_fqs_loop kernel/rcu/tree.c:2004 [inline] rcu_gp_kthread+0xd1a/0x2300 kernel/rcu/tree.c:2177 kthread+0x3e5/0x4d0 kernel/kthread.c:319 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: 858 Comm: syz-executor.5 Not tainted 5.13.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:arch_safe_halt arch/x86/include/asm/irqflags.h:90 [inline] RIP: 0010:kvm_wait arch/x86/kernel/kvm.c:888 [inline] RIP: 0010:kvm_wait+0xaf/0xf0 arch/x86/kernel/kvm.c:871 Code: 10 c3 c3 89 74 24 0c 48 89 3c 24 e8 6b 7c 48 00 8b 74 24 0c 48 8b 3c 24 eb 82 e8 7c 81 48 00 eb 07 0f 00 2d f3 cf 55 08 fb f4 9b eb 07 0f 00 2d e6 cf 55 08 f4 eb c5 89 74 24 0c 48 89 3c 24 RSP: 0018:ffffc90000dc0a18 EFLAGS: 00000206 RAX: 000000000097bd82 RBX: ffff8880b9c52840 RCX: 1ffffffff1f9b2ba RDX: 0000000000000000 RSI: 0000000000000102 RDI: 0000000000000000 RBP: ffff8880b9d52854 R08: 0000000000000001 R09: ffffffff8fcb3907 R10: 0000000000000001 R11: 0000000000000080 R12: ffffed101738a50a R13: ffff8880b9c52854 R14: dffffc0000000000 R15: ffff8880b9d52840 FS: 00007fb1fd6d1700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb1fd6b0718 CR3: 0000000095b33000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: pv_wait arch/x86/include/asm/paravirt.h:597 [inline] pv_wait_node kernel/locking/qspinlock_paravirt.h:325 [inline] __pv_queued_spin_lock_slowpath+0x6c8/0xb40 kernel/locking/qspinlock.c:473 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:585 [inline] queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline] queued_spin_lock include/asm-generic/qspinlock.h:85 [inline] do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:113 spin_lock include/linux/spinlock.h:354 [inline] mac80211_hwsim_tx_frame_no_nl.isra.0+0x68f/0x1330 drivers/net/wireless/mac80211_hwsim.c:1516 mac80211_hwsim_tx_frame+0x1ee/0x2a0 drivers/net/wireless/mac80211_hwsim.c:1784 mac80211_hwsim_beacon_tx+0x4b7/0x920 drivers/net/wireless/mac80211_hwsim.c:1838 __iterate_interfaces+0x1e5/0x520 net/mac80211/util.c:793 ieee80211_iterate_active_interfaces_atomic+0x8d/0x170 net/mac80211/util.c:829 mac80211_hwsim_beacon+0xd5/0x1a0 drivers/net/wireless/mac80211_hwsim.c:1861 __run_hrtimer kernel/time/hrtimer.c:1537 [inline] __hrtimer_run_queues+0x609/0xe40 kernel/time/hrtimer.c:1601 hrtimer_run_softirq+0x17b/0x360 kernel/time/hrtimer.c:1618 __do_softirq+0x29b/0x9bd kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x16e/0x1c0 kernel/softirq.c:636 irq_exit_rcu+0x5/0x20 kernel/softirq.c:648 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1100 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:preempt_schedule_irq+0x49/0x90 kernel/sched/core.c:6328 Code: 55 53 65 48 8b 1c 25 00 f0 01 00 48 89 dd 48 c1 ed 03 48 01 c5 bf 01 00 00 00 e8 62 d7 2d f8 e8 cd ff 59 f8 fb bf 01 00 00 00 b2 cd ff ff 9c 58 fa f6 c4 02 75 27 bf 01 00 00 00 e8 70 c6 2d RSP: 0018:ffffc90017f07338 EFLAGS: 00000202 RAX: 0000000000000e29 RBX: ffff888025cf9c40 RCX: 1ffffffff1ad59e1 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 RBP: ffffed1004b9f388 R08: 0000000000000001 R09: 0000000000000001 R10: ffffffff817b9778 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 irqentry_exit+0x31/0x80 kernel/entry/common.c:427 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:__ipv6_dev_get_saddr+0xee/0x5c0 net/ipv6/addrconf.c:1662 Code: 48 c1 e8 03 48 01 d0 48 89 44 24 28 e8 2b d8 ac f9 48 8d 7d 6c 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03 0f b6 14 08 <48> 89 f8 83 e0 07 83 c0 03 38 d0 7c 08 84 d2 0f 85 1c 04 00 00 8b RSP: 0018:ffffc90017f07400 EFLAGS: 00000a07 RAX: 1ffff110110a538d RBX: ffff888088529d58 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: ffffffff87c8a9c5 RDI: ffff888088529c6c RBP: ffff888088529c00 R08: 000000000000000b R09: ffffc90017f0751f R10: ffffffff87c8ab23 R11: 000000000000000a R12: 000000000000000b R13: ffffc90017f07508 R14: ffff888091380000 R15: ffffc90017f074a8 ipv6_dev_get_saddr+0x832/0xba0 net/ipv6/addrconf.c:1817 ip6_route_get_saddr include/net/ip6_route.h:145 [inline] ip6_dst_lookup_tail+0xb6a/0x15f0 net/ipv6/ip6_output.c:1067 ip6_dst_lookup_flow+0x8c/0x1d0 net/ipv6/ip6_output.c:1192 ip6_sk_dst_lookup_flow+0x598/0x9d0 net/ipv6/ip6_output.c:1230 udpv6_sendmsg+0x18f0/0x2c40 net/ipv6/udp.c:1508 inet6_sendmsg+0x99/0xe0 net/ipv6/af_inet6.c:642 sock_sendmsg_nosec net/socket.c:702 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:722 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2385 ___sys_sendmsg+0xf3/0x170 net/socket.c:2439 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2468 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: 0033:0x4665d9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fb1fd6d1188 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 000000000056bf80 RCX: 00000000004665d9 RDX: 0000000000000000 RSI: 0000000020000480 RDI: 0000000000000003 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000056bf80 R13: 00007ffce6e5a9ff R14: 00007fb1fd6d1300 R15: 0000000000022000