rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 0, t=10502 jiffies, g=16777, q=389 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10495 (4294959201-4294948706), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread timer wakeup didn't happen for 10494 jiffies! g16777 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200
rcu: 	Possible timer handling issue on cpu=1 timer-softirq=7237
rcu: rcu_preempt kthread starved for 10495 jiffies! g16777 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x200 ->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 stack:27304 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00004000
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x12b/0x270
 rcu_gp_fqs_loop+0x301/0x1540
 rcu_gp_kthread+0x99/0x390
 kthread+0x711/0x8a0
 ret_from_fork+0x439/0x7d0
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7846 Comm: syz.2.501 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:hrtimer_try_to_cancel+0x0/0x420
Code: ef e8 d4 35 76 00 e9 c4 fe ff ff 66 66 66 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 30 48 89 fb 49
RSP: 0018:ffffc900001e0988 EFLAGS: 00000006
RAX: ffffffff81adabe1 RBX: ffff888110982d28 RCX: ffff88803850d640
RDX: 0000000000010000 RSI: 0000000000000004 RDI: ffff888110982d28
RBP: 00000000ffffffff R08: ffff888136627a83 R09: 1ffff11026cc4f50
R10: dffffc0000000000 R11: ffffed1026cc4f51 R12: ffff888110982dd0
R13: dffffc0000000000 R14: ffff888110982d28 R15: ffffffffffff4fc8
FS:  00007f31c43f06c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c35e050 CR3: 000000010b17c000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 hrtimer_cancel+0x3b/0x50
 cpu_clock_event_stop+0xd9/0x130
 __perf_event_overflow+0x580/0xe40
 perf_swevent_hrtimer+0x3c5/0x550
 __hrtimer_run_queues+0x4e0/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:unwind_get_return_address+0x51/0x90
Code: 3b 00 74 3a 48 83 c3 48 49 89 df 49 c1 ef 03 43 80 3c 37 00 74 08 48 89 df e8 bb 0b b1 00 48 8b 3b e8 63 c1 19 00 85 c0 74 14 <43> 80 3c 37 00 74 08 48 89 df e8 a0 0b b1 00 48 8b 03 eb 02 31 c0
RSP: 0018:ffffc90006f077e8 EFLAGS: 00000202
RAX: 0000000000000001 RBX: ffffc90006f07850 RCX: bdb83e3aec586500
RDX: 0000000000000001 RSI: ffffffff8dbaa3f5 RDI: ffffffff8a2ab160
RBP: ffffc90006f07890 R08: ffffc90006f07d80 R09: 0000000000000000
R10: ffffc90006f07858 R11: fffff52000de0f0d R12: ffff88803850d640
R13: ffff88810a1ae780 R14: dffffc0000000000 R15: 1ffff92000de0f0a
 arch_stack_walk+0xfc/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 ref_tracker_alloc+0x133/0x460
 sk_alloc+0x1b1/0x370
 inet6_create+0x7f0/0x1260
 __sock_create+0x4b3/0x9f0
 __sys_socket+0xd7/0x1b0
 __x64_sys_socket+0x7a/0x90
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f31c358ec29
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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f31c43f0038 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: ffffffffffffffda RBX: 00007f31c37d5fa0 RCX: 00007f31c358ec29
RDX: 0000000000000011 RSI: 0000000000000002 RDI: 000000000000000a
RBP: 00007f31c3611e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f31c37d6038 R14: 00007f31c37d5fa0 R15: 00007ffc2683b3f8
 </TASK>
