rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P17544/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=71485, q=447 ncpus=2)
task:syz.9.3200      state:R  running task     stack:23480 pid:17544 tgid:17541 ppid:16936  task_flags:0x400140 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
 copy_pmd_range+0x68c6/0x71d0
 copy_page_range+0xc14/0x1270
 dup_mmap+0xf57/0x1ac0
 copy_mm+0x13c/0x4b0
 copy_process+0x1706/0x3c00
 kernel_clone+0x21e/0x840
 __x64_sys_clone+0x18b/0x1e0
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f04d918ec29
RSP: 002b:00007f04d9f87fe8 EFLAGS: 00000206 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 00007f04d93d5fa0 RCX: 00007f04d918ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000008010e000
RBP: 00007f04d9211e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f04d93d6038 R14: 00007f04d93d5fa0 R15: 00007ffdbc6e5ba8
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10496 jiffies! g71485 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=35035
rcu: rcu_preempt kthread starved for 10497 jiffies! g71485 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:27160 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 17570 Comm: syz.3.3208 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:validate_chain+0xa4/0x2140
Code: c6 de cd a9 8d e8 dc a5 e5 ff 90 0f 0b 90 90 90 48 bb eb 83 b5 80 46 86 c8 61 49 0f af df 48 c1 eb 2d 48 8b 04 dd 40 73 64 93 <48> 85 c0 0f 94 c1 48 83 c0 f8 0f 94 c2 08 ca 0f 84 24 01 00 00 e8
RSP: 0018:ffffc90000007638 EFLAGS: 00000006
RAX: ffffffff93a89018 RBX: 000000000002c50a RCX: 0000000000040000
RDX: 0000000000000001 RSI: ffff88802293c470 RDI: ffff88802293b980
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff81ada58b
R10: dffffc0000000000 R11: ffffed1009604f51 R12: 0000000000000001
R13: ffff88802293c470 R14: ffff88802293c470 R15: d6bf87c490213bdc
FS:  00007f2a9ffb16c0(0000) GS:ffff8880b8615000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000003c9c2000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 __lock_acquire+0xab9/0xd20
 lock_acquire+0x120/0x360
 _raw_spin_lock_irqsave+0xa7/0xf0
 hrtimer_try_to_cancel+0x22b/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:unwind_next_frame+0xb0/0x2390
Code: 32 02 00 00 89 84 24 84 00 00 00 4c 89 bc 24 90 00 00 00 e8 f2 57 34 00 4c 8d 3d 00 00 00 00 48 c7 c7 e0 a0 13 8e 31 f6 31 d2 <b9> 02 00 00 00 45 31 c0 45 31 c9 41 57 e8 7e 9b 2a 00 48 83 c4 08
RSP: 0018:ffffc90004487858 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff8172fa38 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e13a0e0
RBP: dffffc0000000000 R08: ffffc90004487901 R09: 0000000000000000
R10: ffffc90004487988 R11: fffff52000890f3d R12: 1ffff92000890f31
R13: ffffc900044879c0 R14: ffffc90004487988 R15: ffffffff8172d195
 __unwind_start+0x5b9/0x760
 arch_stack_walk+0xe4/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_slab_alloc+0x6c/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 getname_flags+0xb8/0x540
 do_sys_openat2+0xbc/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2a9f18ec29
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:00007f2a9ffb1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f2a9f3d5fa0 RCX: 00007f2a9f18ec29
RDX: 0000000000200002 RSI: 0000200000000200 RDI: ffffffffffffffff
RBP: 00007f2a9f211e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f2a9f3d6038 R14: 00007f2a9f3d5fa0 R15: 00007ffd036d87a8
 </TASK>
