rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=69fc/1/0x4000000000000000 softirq=45967/45967 fqs=0
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P10511/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=34441, q=861 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10518 Comm: syz.3.1072 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+0x2a2/0x3e0
Code: dd 09 b8 ff ff ff ff 65 0f c1 05 09 c9 03 11 83 f8 01 75 51 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 <75> 56 f7 c3 00 02 00 00 74 01 fb 65 48 8b 05 cb 88 03 11 48 3b 44
RSP: 0018:ffffc90000007818 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000087 RCX: 33dd5bb0d9b84100
RDX: 0000000000000001 RSI: ffffffff8dbaacc4 RDI: ffffffff8be34480
RBP: ffff888021804498 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: 0000000000000001
R13: 0000000000000001 R14: ffff88804b027a98 R15: ffff888021803980
FS:  00007f0eacda66c0(0000) GS:ffff8880b860f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000044c0 CR3: 00000001186ea000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000082
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
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:preempt_schedule+0x0/0xc0
Code: 00 00 e8 83 c2 13 f6 c3 cc cc cc cc cc 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 48 89 e5 41 56 53 48 83 e4 e0 48 83 ec 60 65 48 8b
RSP: 0018:ffffc9000267f600 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000201 RCX: 33dd5bb0d9b84100
RDX: 0000000000000006 RSI: ffffffff8d9bb5e6 RDI: ffffffff8be34480
RBP: ffffc9000267f650 R08: ffffffff8fa3c237 R09: 1ffffffff1f47846
R10: dffffc0000000000 R11: fffffbfff1f47847 R12: ffffffff89a1f1f3
R13: dffffc0000000000 R14: dffffc0000000000 R15: 1ffff920004cfecc
 preempt_schedule_thunk+0x16/0x30
 __local_bh_enable_ip+0x13e/0x1c0
 netlink_insert+0xd3/0x1370
 netlink_autobind+0x22e/0x300
 netlink_sendmsg+0x523/0xb30
 __sock_sendmsg+0x21c/0x270
 ____sys_sendmsg+0x505/0x830
 ___sys_sendmsg+0x21f/0x2a0
 __x64_sys_sendmsg+0x19b/0x260
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0eabf8ec29
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:00007f0eacda6038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f0eac1d6090 RCX: 00007f0eabf8ec29
RDX: 0000000000000000 RSI: 0000200000000140 RDI: 0000000000000007
RBP: 00007f0eac011e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f0eac1d6128 R14: 00007f0eac1d6090 R15: 00007ffe5c913c78
 </TASK>
task:syz.5.1070      state:R  running task     stack:24328 pid:10511 tgid:10510 ppid:6099   task_flags:0x40054c flags:0x00004002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 preempt_schedule_common+0x83/0xd0
 preempt_schedule+0xae/0xc0
 preempt_schedule_thunk+0x16/0x30
 _raw_spin_unlock+0x3f/0x50
 unmap_page_range+0x3a79/0x4370
 unmap_vmas+0x399/0x580
 exit_mmap+0x248/0xb50
 __mmput+0x118/0x430
 exit_mm+0x1da/0x2c0
 do_exit+0x648/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa08198ec29
RSP: 002b:00007fa082806fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: fffffffffffffffc RBX: 00007fa081bd5fa0 RCX: 00007fa08198ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000041064400
RBP: 00007fa081a11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007fa081bd6038 R14: 00007fa081bd5fa0 R15: 00007ffd720674d8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10501 jiffies! g34441 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=18085
rcu: rcu_preempt kthread starved for 10502 jiffies! g34441 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:26344 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>
