rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (1 GPs behind) idle=0e64/1/0x4000000000000000 softirq=33296/33297 fqs=0
rcu: 	(detected by 1, t=10506 jiffies, g=24137, q=285 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9006 Comm: syz.3.906 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+0x29a/0x3e0
Code: c7 a5 a5 ba 8d e8 66 9b dd 09 b8 ff ff ff ff 65 0f c1 05 09 a9 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
RSP: 0018:ffffc90000007818 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000087 RCX: c176e873038e6900
RDX: 0000000000000000 RSI: ffffffff8dbaa5a5 RDI: ffffffff8be34480
RBP: ffff88810dc527b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: 0000000000000000
R13: 0000000000000000 R14: ffff88804b027a98 R15: ffff88810dc51cc0
FS:  00007fb582f746c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffce17df000 CR3: 0000000028582000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000082 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:dentry_free+0x0/0x150
Code: 84 ff 48 83 c4 28 5b 41 5c 41 5d 41 5e 41 5f 5d c3 cc cc cc cc cc 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <55> 41 57 41 56 41 54 53 48 89 fb 49 bf 00 00 00 00 00 fc ff df e8
RSP: 0018:ffffc90003207d00 EFLAGS: 00000287
RAX: ffffffff823ae19a RBX: ffff88802d1a4000 RCX: 0000000000080000
RDX: ffffc90003449000 RSI: 000000000000015b RDI: ffff88802d1a4000
RBP: 0000000000000000 R08: ffff88802d1a40bb R09: 1ffff11005a34817
R10: dffffc0000000000 R11: ffffed1005a34818 R12: ffff88802d1a40b8
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000
 __dentry_kill+0x4d2/0x660
 dput+0x19f/0x2b0
 __fput+0x68e/0xa70
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb58218ec29
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:00007fb582f74038 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: 0000000000000000 RBX: 00007fb5823d5fa0 RCX: 00007fb58218ec29
RDX: 0000000000032120 RSI: 0000200000000000 RDI: 0000000000000006
RBP: 00007fb582211e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb5823d6038 R14: 00007fb5823d5fa0 R15: 00007ffc206ebca8
 </TASK>
rcu: rcu_preempt kthread starved for 10506 jiffies! g24137 f0x0 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:26920 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: 1 UID: 0 PID: 9005 Comm: syz.3.906 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_single+0x3ae/0x590
Code: e6 01 31 ff e8 83 7a 0b 00 41 83 e6 01 75 11 e8 38 76 0b 00 4d 89 fe eb 3f e8 2e 76 0b 00 eb 3c 4d 89 fe f3 90 43 0f b6 04 2c <84> c0 75 0f f7 03 01 00 00 00 74 1d e8 11 76 0b 00 eb e6 89 d9 80
RSP: 0018:ffffc90003bcfa40 EFLAGS: 00000293
RAX: 0000000000000000 RBX: ffffc90003bcfa88 RCX: ffff88810dc50000
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003bcfb30 R08: ffffc90003bcf8e7 R09: 1ffff92000779f1c
R10: dffffc0000000000 R11: fffff52000779f1d R12: 1ffff92000779f51
R13: dffffc0000000000 R14: 1ffff92000779f4c R15: 1ffff92000779f4c
FS:  000055557f0fe500(0000) GS:ffff8881a3c11000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555564fdf5c8 CR3: 0000000028582000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 event_function_call+0x326/0x970
 perf_event_release_kernel+0x15d/0x510
 perf_release+0x38/0x50
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 exit_to_user_mode_loop+0xec/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb58218ec29
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:00007ffc206ebe08 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007fb5823d7da0 RCX: 00007fb58218ec29
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 00007fb5823d7da0 R08: 0000000000010924 R09: 0000001e206ec0ff
R10: 00007fb5823d7cb0 R11: 0000000000000246 R12: 0000000000029b22
R13: 00007fb5823d6180 R14: ffffffffffffffff R15: 00007ffc206ebf20
 </TASK>
