rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=0f2c/1/0x4000000000000000 softirq=34359/34362 fqs=141
rcu: 	(detected by 1, t=10502 jiffies, g=28661, q=1286 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 9798 Comm: syz.4.1080 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:check_preemption_disabled+0x17/0x120
Code: 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 41 56 53 48 83 ec 10 65 48 8b 05 de 64 43 07 48 89 44 24 08 <65> 8b 05 e6 64 43 07 65 8b 0d db 64 43 07 f7 c1 ff ff ff 7f 74 23
RSP: 0018:ffffc900000077e0 EFLAGS: 00000082
RAX: cd785744ced48800 RBX: 0000000000000083 RCX: cd785744ced48800
RDX: 0000000000000001 RSI: ffffffff8dd8c8ae RDI: ffffffff8c03d4e0
RBP: ffff888109a68b58 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: 0000000000000001
R13: 0000000000000001 R14: ffff88804b027ad8 R15: ffff888109a68000
FS:  00007f5e885986c0(0000) GS:ffff8880b8403000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000000000 CR3: 000000010cc5e000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 lock_release+0x27a/0x3e0
 _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+0x3b8/0x500
 __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:read_seqbegin+0x0/0x200
Code: 41 5e 41 5f 5d e9 90 c2 41 09 cc e8 3a e4 80 ff e9 43 ff ff ff 0f 1f 44 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 57 41 56 41 54 53 48 83 e4 e0 48 81 ec
RSP: 0018:ffffc900063bf818 EFLAGS: 00000a06
RAX: 1ffff92000c77f35 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc90007eb1000 RSI: 0000000000000156 RDI: 0000000000000157
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff823f6cd6
R10: dffffc0000000000 R11: ffffed10095820a5 R12: ffffc900063bf9a8
R13: 1ffff92000c77f34 R14: dffffc0000000000 R15: ffffc900063bf9a0
 lookup_mnt+0xf9/0x570
 __traverse_mounts+0x1c1/0x5e0
 step_into+0x4f2/0xe80
 link_path_walk+0x77b/0xea0
 __filename_parentat+0x246/0x670
 filename_create+0xd2/0x3c0
 do_mkdirat+0xa0/0x590
 __x64_sys_mkdirat+0x87/0xa0
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5e8778ec29
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:00007f5e88598038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f5e879d5fa0 RCX: 00007f5e8778ec29
RDX: 00000000000001ff RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f5e87811e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5e879d6038 R14: 00007f5e879d5fa0 R15: 00007ffe6323e1f8
 </TASK>
rcu: rcu_preempt kthread starved for 10220 jiffies! g28661 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:27224 pid:16    tgid:16    ppid:2      task_flags:0x208040 flags:0x00080000
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+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
CPU: 1 UID: 0 PID: 9221 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:__sanitizer_cov_trace_pc+0x37/0x70
Code: 08 d0 c1 92 65 8b 15 c8 79 01 11 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 7c 16 00 00 00 74 2c 8b 91 58 16 00 00 <83> fa 02 75 21 48 8b 91 60 16 00 00 48 8b 32 48 8d 7e 01 8b 89 5c
RSP: 0000:ffffc900037776f8 EFLAGS: 00000246
RAX: ffffffff81b4e79b RBX: 1ffff11009608441 RCX: ffff888105cc9d00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90003777880 R08: ffffffff8fc34277 R09: 1ffffffff1f8684e
R10: dffffc0000000000 R11: fffffbfff1f8684f R12: ffff88804b042208
R13: dffffc0000000000 R14: ffff88813663b200 R15: 0000000000000000
FS:  000055556a042500(0000) GS:ffff8881a3a03000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055556a05d5c8 CR3: 00000001075b8000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 smp_call_function_many_cond+0xd4b/0x12d0
 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+0x1033/0x5400
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0xa7c/0x1380
 exc_page_fault+0x82/0x100
 asm_exc_page_fault+0x26/0x30
RIP: 0033:0x7f3abc94d08f
Code: 8d 34 19 48 39 d5 48 89 75 60 0f 95 c2 48 29 d8 48 83 c1 10 0f b6 d2 48 83 c8 01 48 c1 e2 02 48 09 da 48 83 ca 01 48 89 51 f8 <48> 89 46 08 eb 80 48 8d 0d d1 e8 0e 00 48 8d 15 d5 fa 0e 00 bf 01
RSP: 002b:00007ffdc9253c10 EFLAGS: 00010206
RAX: 0000000000018a41 RBX: 0000000000008040 RCX: 000055556a055590
RDX: 0000000000008041 RSI: 000055556a05d5c0 RDI: 0000000000000004
RBP: 00007f3abcba7cc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000001000 R11: 0000000000000802 R12: 0000000000008030
R13: 0000000000000076 R14: 00007f3abcba7d20 R15: 0000000000000000
 </TASK>
