rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	1-...!: (0 ticks this GP) idle=831c/1/0x4000000000000000 softirq=13479/13479 fqs=0
rcu: 	(detected by 0, t=10502 jiffies, g=6289, q=262 ncpus=2)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 5909 Comm: syz.2.3 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:lock_release+0xaa/0x3e0
Code: 92 41 83 bf ec 0a 00 00 00 0f 85 1e 02 00 00 49 81 3e 20 a3 64 93 0f 84 11 02 00 00 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 <48> 8b 5c 24 20 fa 48 c7 c7 53 e5 9c 8d e8 64 61 dd 09 65 ff 05 0d
RSP: 0018:ffffc900001e0818 EFLAGS: 00000087
RAX: 0000000000000000 RBX: 0000000000000802 RCX: e8433f5720520e00
RDX: 0000000000010000 RSI: ffffffff8be34260 RDI: ffffffff8be34220
RBP: ffffc900001e0918 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200003c100 R12: dffffc0000000000
R13: ffffffff81ada91e R14: ffff888136627a98 R15: ffff88801db11cc0
FS:  00007f762afd56c0(0000) GS:ffff8881a3c12000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000100000001 CR3: 0000000028ea6000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 _raw_spin_unlock_irqrestore+0x70/0x110
 hrtimer_try_to_cancel+0x3be/0x420
 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:_raw_spin_unlock_irqrestore+0xa8/0x110
Code: 74 05 e8 2b 0c 4a f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> e3 b0 12 f6 65 8b 05 6c 81 23 07 85 c0 74 40 48 c7 04 24 0e 36
RSP: 0018:ffffc900039afa40 EFLAGS: 00000206
RAX: e8433f5720520e00 RBX: 0000000000000a06 RCX: e8433f5720520e00
RDX: 0000000000000006 RSI: ffffffff8d9baa25 RDI: 0000000000000001
RBP: ffffc900039afad0 R08: ffffffff8fa3b237 R09: 1ffffffff1f47646
R10: dffffc0000000000 R11: fffffbfff1f47647 R12: dffffc0000000000
R13: ffff88811d830ab8 R14: ffffffff99d90a70 R15: 1ffff92000735f48
 debug_object_activate+0x2e2/0x420
 kvfree_call_rcu+0x4f/0x410
 do_ip_setsockopt+0x287a/0x2d00
 ip_setsockopt+0x66/0x110
 smc_setsockopt+0x232/0xab0
 do_sock_setsockopt+0x17c/0x1b0
 __x64_sys_setsockopt+0x13f/0x1b0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f762cd8ec29
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:00007f762afd5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f762cfd6090 RCX: 00007f762cd8ec29
RDX: 0000000000000004 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00007f762ce11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f762cfd6128 R14: 00007f762cfd6090 R15: 00007ffe8dad3618
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g6289 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0
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:27224 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:
CPU: 0 UID: 0 PID: 5845 Comm: syz-executor 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:smp_call_function_many_cond+0xd38/0x12d0
Code: 89 ee 83 e6 01 31 ff e8 b6 63 0b 00 41 83 e5 01 49 bd 00 00 00 00 00 fc ff df 75 07 e8 61 5f 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 45 5f 0b 00 eb e4 44
RSP: 0000:ffffc9000323f720 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11026cc7f61 RCX: ffff888105ca8000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc9000323f8a0 R08: ffffffff8fa3b237 R09: 1ffffffff1f47646
R10: dffffc0000000000 R11: fffffbfff1f47647 R12: ffff88813663fb08
R13: dffffc0000000000 R14: ffff88804b03b1c0 R15: 0000000000000001
FS:  0000555570c6d500(0000) GS:ffff8880b8612000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1066da2608 CR3: 000000002453a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80
 flush_tlb_mm_range+0x6b1/0x12d0
 ptep_clear_flush+0x120/0x170
 do_wp_page+0x1bc2/0x5800
 __handle_mm_fault+0x1033/0x5440
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0xa81/0x1390
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f1066b66e60
Code: 08 48 8b 06 48 83 c6 08 49 89 c1 4d 01 c1 73 1a 49 31 c1 4d 09 c1 49 ff c1 75 0f 48 89 02 48 83 c2 08 e9 73 ff ff ff 0f 1f 00 <88> 02 84 c0 74 12 48 ff c2 88 22 84 e4 74 09 48 ff c2 48 c1 e8 10
RSP: 002b:00007ffd6950cc78 EFLAGS: 00010296
RAX: 66007265746c6966 RBX: 00007f1066da2608 RCX: 0000000000000000
RDX: 00007f1066da2608 RSI: 00007f1066c13230 RDI: 00007f1066da2608
RBP: 00007f1066c13228 R08: fefefefefefefeff R09: ff00000000000000
R10: 00007f1066da1f88 R11: 0000000000000202 R12: 0000000000000003
R13: 00007f1066da1280 R14: 0000000000000003 R15: 00007ffd6950d370
 </TASK>
