GRED: Unable to relocate VQ 0x0 after dequeue, screwing up backlog
rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	(detected by 1, t=10502 jiffies, g=192045, q=281 ncpus=2)
rcu: All QSes seen, last rcu_preempt kthread activity 10498 (4295055651-4295045153), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10498 jiffies! g192045 f0x2 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:27648 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_timeout+0x158/0x2c0
 rcu_gp_fqs_loop+0x312/0x11d0
 rcu_gp_kthread+0x9e/0x2b0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 26243 Comm: syz.5.3796 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:smp_call_function_many_cond+0xcf6/0x12c0
Code: 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 6f e2 0b 00 eb 38 f3 90 42 0f b6 04 2b 84 c0 75 11 41 f7 04 24 01 00 00 00 <74> 1e e8 53 e2 0b 00 eb e4 44 89 e1 80 e1 07 80 c1 03 38 c1 7c e2
RSP: 0000:ffffc90008fcf840 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 1ffff11024208559 RCX: 0000000000080000
RDX: ffffc90029f5b000 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90008fcf970 R08: ffffffff9011e8b7 R09: 1ffffffff2023d16
R10: dffffc0000000000 R11: fffffbfff2023d17 R12: ffff888121042ac8
R13: dffffc0000000000 R14: ffff88823c63bf80 R15: 0000000000000000
FS:  00007f7896bc06c0(0000) GS:ffff8882a9462000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f788ba00400 CR3: 00000001a852c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80
 flush_tlb_mm_range+0x5c3/0x10c0
 ptep_clear_flush+0x120/0x170
 do_wp_page+0x3da7/0x4cc0
 handle_mm_fault+0x151d/0x3170
 do_user_addr_fault+0xa73/0x1340
 exc_page_fault+0x6a/0xc0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f7895c53ae3
Code: 1f 84 00 00 00 00 00 3d 00 01 00 00 75 29 45 31 f6 48 83 c4 18 44 89 f0 5b 5d 41 5c 41 5d 41 5e 41 5f c3 0f 1f 40 00 49 8b 0f <44> 88 34 01 49 83 47 10 01 eb 92 66 90 8d 90 ff fe ff ff 83 fa 1c
RSP: 002b:00007f7896bbf470 EFLAGS: 00010202
RAX: 0000000000000400 RBX: 00007f7896bbf530 RCX: 00007f788ba00000
RDX: 00007f7896bbf6d0 RSI: 0000000000000019 RDI: 00007f7896bbf5d0
RBP: 00000000000000f9 R08: 0000000000000008 R09: 00000000000000a7
R10: 00000000000000be R11: 00007f7896bbf530 R12: 0000000000000001
R13: 00007f7895e52600 R14: 0000000000000020 R15: 00007f7896bbf5d0
 </TASK>
