rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	0-...!: (10499 ticks this GP) idle=f32/1/0x4000000000000000 softirq=181933/181933 fqs=0 
	(t=10500 jiffies g=313493 q=32)
rcu: rcu_preempt kthread starved for 10500 jiffies! g313493 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:28896 pid:   10 ppid:     2 flags:0x00004000
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x979/0xce0 kernel/sched/core.c:4527
NMI backtrace for cpu 0
CPU: 0 PID: 20037 Comm: syz-executor.2 Not tainted 5.9.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1f0/0x31e lib/dump_stack.c:118
 nmi_cpu_backtrace+0x9f/0x180 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x16a/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x199/0x2a0 kernel/rcu/tree_stall.h:318
 print_cpu_stall kernel/rcu/tree_stall.h:551 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:625 [inline]
 rcu_pending kernel/rcu/tree.c:3637 [inline]
 rcu_sched_clock_irq+0x1920/0x1eb0 kernel/rcu/tree.c:2519
 update_process_times+0x130/0x1b0 kernel/time/timer.c:1710
 tick_sched_handle kernel/time/tick-sched.c:176 [inline]
 tick_sched_timer+0x25e/0x410 kernel/time/tick-sched.c:1328
 __run_hrtimer kernel/time/hrtimer.c:1524 [inline]
 __hrtimer_run_queues+0x42d/0x930 kernel/time/hrtimer.c:1588
 hrtimer_interrupt+0x373/0xd60 kernel/time/hrtimer.c:1650
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1080 [inline]
 __sysvec_apic_timer_interrupt+0xf0/0x260 arch/x86/kernel/apic/apic.c:1097
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:50 [inline]
 sysvec_apic_timer_interrupt+0xd0/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:__kasan_kmalloc+0x12b/0x130 mm/kasan/common.c:464
Code: 89 f7 89 c6 e8 36 ec 07 02 4c 89 f7 89 c6 8b 54 24 0c e8 b8 e7 07 02 41 89 44 1c 04 4c 89 e0 48 8d 65 d8 5b 41 5c 41 5d 41 5e <41> 5f 5d c3 90 e9 cb fe ff ff 90 66 2e 0f 1f 84 00 00 00 00 00 55
RSP: 0018:ffffc90000007c48 EFLAGS: 00000286
RAX: ffff888202294000 RBX: ffffffff868db42e RCX: ffffffff88600236
RDX: 0000000000082a20 RSI: ffffc90000007a4c RDI: 00000000bfcfafd5
RBP: ffffc90000007c50 R08: 0000000000000003 R09: 0000000000000009
R10: ffffffff88600000 R11: ffffffff8860066c R12: 0000000000000a20
R13: ffff88820228ee00 R14: 00000000ffffffff R15: ffff88820229473f
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0xde/0x4f0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1085 [inline]
 mrp_pdu_init net/802/mrp.c:300 [inline]
 mrp_pdu_append_vecattr_event+0x15e/0x1630 net/802/mrp.c:399
 mrp_attr_event+0x149/0x260 net/802/mrp.c:494
 mrp_mad_event net/802/mrp.c:574 [inline]
 mrp_join_timer+0x5b/0x130 net/802/mrp.c:591
 call_timer_fn+0x91/0x160 kernel/time/timer.c:1413
 expire_timers kernel/time/timer.c:1458 [inline]
 __run_timers+0x65e/0x830 kernel/time/timer.c:1755
 run_timer_softirq+0x46/0x80 kernel/time/timer.c:1768
 __do_softirq+0x236/0x66c kernel/softirq.c:298
 asm_call_on_stack+0xf/0x20 arch/x86/entry/entry_64.S:706
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:22 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:48 [inline]
 do_softirq_own_stack+0x91/0xe0 arch/x86/kernel/irq_64.c:77
 invoke_softirq kernel/softirq.c:393 [inline]
 __irq_exit_rcu+0x1e1/0x1f0 kernel/softirq.c:423
 irq_exit_rcu+0x5/0x10 kernel/softirq.c:435
 sysvec_apic_timer_interrupt+0xd5/0xf0 arch/x86/kernel/apic/apic.c:1091
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:581
RIP: 0010:tcp_highest_sack_seq include/net/tcp.h:1877 [inline]
RIP: 0010:tcp_ack+0x59d/0x6c70 net/ipv4/tcp_input.c:3651
Code: 18 31 ff 89 de e8 33 a4 84 fa 66 85 db 0f 88 5d 03 00 00 e8 b5 a0 84 fa 4c 89 ef e8 9d 93 01 00 bb ff ff ff ff e9 7a 41 00 00 <e8> 9e a0 84 fa 48 8b 6c 24 28 e9 aa 00 00 00 e8 8f a0 84 fa e9 61
RSP: 0018:ffffc9000491f928 EFLAGS: 00000246
RAX: 0000000000000002 RBX: ffff8880334e5ac1 RCX: ffff8880334e5ca4
RDX: ffff88820c458500 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff86f05584 R09: ffffc9000491fb00
R10: fffff52000923f67 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880334e5380 R14: 000000000000771b R15: 1ffff92000923f5f
 tcp_rcv_state_process+0x4ea/0x2360 net/ipv4/tcp_input.c:6292
 tcp_v4_do_rcv+0x5a5/0x860 net/ipv4/tcp_ipv4.c:1664
 sk_backlog_rcv include/net/sock.h:1011 [inline]
 __release_sock+0x1b2/0x480 net/core/sock.c:2542
 release_sock+0x5d/0x1c0 net/core/sock.c:3065
 tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1442
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg net/socket.c:671 [inline]
 __sys_sendto+0x42a/0x5c0 net/socket.c:1992
 __do_sys_sendto net/socket.c:2004 [inline]
 __se_sys_sendto net/socket.c:2000 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2000
 do_syscall_64+0x31/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45d5b9
Code: 5d b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 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 0f 83 2b b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f11735c9c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 000000000002d140 RCX: 000000000045d5b9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 000000000118cf98 R08: 0000000020e68000 R09: 0000000000000010
R10: 00000000220007fd R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007ffe85ecdf8f R14: 00007f11735ca9c0 R15: 000000000118cf4c