syzbot

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-...!: (10499 ticks this GP) idle=d7e/1/0x4000000000000002 softirq=10563/10563 fqs=3 
	(t=10501 jiffies g=6417 q=174)
rcu: rcu_preempt kthread starved for 10496 jiffies! g6417 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
rcu: RCU grace-period kthread stack dump:
rcu_preempt     R  running task    29104    10      2 0x80004000
Call Trace:
 context_switch kernel/sched/core.c:3385 [inline]
 __schedule+0x9a0/0xcc0 kernel/sched/core.c:4081
 schedule+0x181/0x210 kernel/sched/core.c:4155
 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895
 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline]
 rcu_gp_kthread+0xed8/0x1770 kernel/rcu/tree.c:1821
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
NMI backtrace for cpu 1
CPU: 1 PID: 8224 Comm: syz-executor.2 Not tainted 5.4.0-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+0x1fb/0x318 lib/dump_stack.c:118
 nmi_cpu_backtrace+0xaf/0x1a0 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x174/0x290 lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254
 print_cpu_stall kernel/rcu/tree_stall.h:455 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:529 [inline]
 rcu_pending kernel/rcu/tree.c:2827 [inline]
 rcu_sched_clock_irq+0xe25/0x1ad0 kernel/rcu/tree.c:2271
 update_process_times+0x12d/0x180 kernel/time/timer.c:1726
 tick_sched_handle kernel/time/tick-sched.c:167 [inline]
 tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1310
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x403/0x840 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x38c/0xda0 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 </IRQ>
RIP: 0010:mod_memcg_page_state+0xb/0x190 include/linux/memcontrol.h:652
Code: 8b 26 2e 00 eb 05 e8 84 26 2e 00 48 83 c4 10 5b 41 5c 41 5d 41 5e 41 5f 5d c3 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 54 53 <41> 89 f6 48 89 fb e8 5a 26 2e 00 48 83 c3 38 48 89 d8 48 c1 e8 03
RSP: 0018:ffffc900021f7a88 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13
RAX: 1ffff11013596711 RBX: ffff88809acb3888 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 00000000fffffffc RDI: ffffea000279c440
RBP: ffffc900021f7aa8 R08: 000000000003a728 R09: fffffbfff120248a
R10: fffffbfff120248a R11: 0000000000000000 R12: ffff88809acb3920
R13: dffffc0000000000 R14: 1ffff11013596724 R15: ffff888098837428
 free_thread_stack+0x168/0x590 kernel/fork.c:280
 release_task_stack kernel/fork.c:440 [inline]
 put_task_stack+0xa3/0x130 kernel/fork.c:451
 finish_task_switch+0x3f1/0x550 kernel/sched/core.c:3256
 context_switch kernel/sched/core.c:3388 [inline]
 __schedule+0x9a8/0xcc0 kernel/sched/core.c:4081
 preempt_schedule_irq+0xc1/0x140 kernel/sched/core.c:4338
 retint_kernel+0x1b/0x2b
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline]
RIP: 0010:lock_acquire+0x1b2/0x250 kernel/locking/lockdep.c:4488
Code: c1 e8 03 42 80 3c 30 00 74 0c 48 c7 c7 28 95 0a 89 e8 42 7c 56 00 48 83 3d 62 02 af 07 00 0f 84 9c 00 00 00 48 8b 7d c0 57 9d <0f> 1f 44 00 00 48 83 c4 30 5b 41 5c 41 5d 41 5e 41 5f 5d c3 44 89
RSP: 0018:ffffc900021f7d08 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff12152a5 RBX: 0000000000000000 RCX: ffffffff815c69d2
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: 0000000000000286
RBP: ffffc900021f7d60 R08: dffffc0000000000 R09: fffffbfff13ca11f
R10: fffffbfff13ca11f R11: 0000000000000000 R12: 0000000000000001
R13: 0000000000000000 R14: dffffc0000000000 R15: ffffffff890fdff0
 __fs_reclaim_acquire+0x24/0x30 mm/page_alloc.c:4084
 fs_reclaim_acquire+0x5f/0xd0 mm/page_alloc.c:4095
 slab_pre_alloc_hook mm/slab.h:562 [inline]
 slab_alloc mm/slab.c:3306 [inline]
 kmem_cache_alloc+0x2a/0x2e0 mm/slab.c:3484
 sock_alloc_inode+0x1b/0xc0 net/socket.c:240
 alloc_inode fs/inode.c:230 [inline]
 new_inode_pseudo+0x68/0x240 fs/inode.c:919
 sock_alloc net/socket.c:560 [inline]
 __sock_create+0x12d/0x910 net/socket.c:1384
 sock_create net/socket.c:1471 [inline]
 __sys_socket+0xe7/0x2e0 net/socket.c:1513
 __do_sys_socket net/socket.c:1522 [inline]
 __se_sys_socket net/socket.c:1520 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1520
 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d1c7
Code: 00 00 00 49 89 ca b8 36 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 4a 8b fb ff c3 66 0f 1f 84 00 00 00 00 00 b8 29 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 2d 8b fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fff3e9a5308 EFLAGS: 00000202 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 0000000000a72200 RCX: 000000000045d1c7
RDX: 0000000000000000 RSI: 0000000000080002 RDI: 0000000000000001
RBP: 00000000004bfbe7 R08: 0000000000000000 R09: 00007fff3e9a5448
R10: 0000000000000000 R11: 0000000000000202 R12: 00000000004bfbe7
R13: 0000000000000000 R14: 0000000000000003 R15: 00007fff3e9a5448