rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=7a44/1/0x4000000000000000 softirq=18958/18958 fqs=0
rcu: 	(detected by 1, t=10502 jiffies, g=10881, q=241 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6462 Comm: syz.0.145 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_acquire+0x79f/0xd20
Code: bb d0 0a 00 00 00 48 89 df 0f 84 17 ff ff ff 48 8b 3c 24 4c 89 f6 ba 07 00 00 00 e9 48 02 00 00 45 8b 66 20 48 83 7c 24 68 00 <4c> 8b 6c 24 10 74 53 83 bf e8 0a 00 00 00 0f 8e f9 00 00 00 31 db
RSP: 0018:ffffc90000006d50 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000002 RCX: ffffffffffffffff
RDX: 00000000ffffc000 RSI: ffff8880227ac4c0 RDI: ffff8880227ab980
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff81adabcb
R10: ffffc90000006be0 R11: ffffffffa000088c R12: 00000000000c6067
R13: 0000000000000002 R14: ffff8880227ac4c0 R15: ffffffffffffffff
FS:  00007f10949376c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c24fd8e CR3: 000000010d9da000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <IRQ>
 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+0x52/0xc0
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:unwind_next_frame+0x1334/0x2390
Code: 0f b6 04 08 84 c0 75 27 49 63 07 4c 01 f8 49 8d 4f 04 4c 39 e0 48 0f 46 e9 49 8d 47 fc 48 0f 47 d8 4d 0f 46 ef 48 39 dd 76 a2 <e9> 7b ef ff ff 44 89 f9 80 e1 07 80 c1 03 38 c1 7c cc 4c 89 ff 48
RSP: 0018:ffffc900000076d8 EFLAGS: 00000212
RAX: ffffffff9027b128 RBX: ffffffff9027b12c RCX: ffffffff9027b130
RDX: ffffffff9027b12c RSI: ffffffff90dbcdee RDI: ffffffff8be34420
RBP: ffffffff9027b130 R08: 0000000000000001 R09: ffffffff8172d195
R10: ffffc90000007440 R11: ffffffffa000088c R12: ffffffff8b7ac019
R13: ffffffff9027b12c R14: ffffc900000077a8 R15: ffffffff9027b12c
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 slab_free_after_rcu_debug+0x60/0x2a0
 rcu_core+0xcab/0x1770
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:preempt_schedule_irq+0xb0/0x150
Code: 24 20 f6 44 24 21 02 74 0c 90 0f 0b 48 f7 03 08 00 00 00 74 64 bf 01 00 00 00 e8 eb ce 13 f6 e8 b6 2b 4b f6 fb bf 01 00 00 00 <e8> 5b ab ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24
RSP: 0018:ffffc90003f97720 EFLAGS: 00000282
RAX: 3c963d28ef4e6d00 RBX: 0000000000000000 RCX: 3c963d28ef4e6d00
RDX: 0000000000000000 RSI: ffffffff8d9baf27 RDI: 0000000000000001
RBP: ffffc90003f977c0 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: 0000000000000000
R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff920007f2ee4
 irqentry_exit+0x6f/0x90
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:fsnotify_open_perm_and_set_mode+0x0/0x610
Code: 00 48 c7 c2 40 0d 9a 8b e8 4d 0c 55 ff e9 64 ff ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <66> 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 20 48 89 fb 49
RSP: 0018:ffffc90003f97888 EFLAGS: 00000246
RAX: ffffffff8233d010 RBX: ffff88810d668a00 RCX: 0000000000000002
RDX: ffff8880227ab980 RSI: 0000000000000000 RDI: ffff88810d668a00
RBP: dffffc0000000000 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: ffff888107376378
R13: ffff88810d668a50 R14: ffff88810d668a48 R15: 0000000000000000
 do_dentry_open+0x474/0x13f0
 vfs_open+0x3b/0x340
 path_openat+0x2ee5/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f1093b8ec29
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:00007f1094937038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f1093dd5fa0 RCX: 00007f1093b8ec29
RDX: 0000000000000000 RSI: 0000200000000180 RDI: ffffffffffffff9c
RBP: 00007f1093c11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1093dd6038 R14: 00007f1093dd5fa0 R15: 00007ffc2b4c8868
 </TASK>
rcu: rcu_preempt kthread starved for 10502 jiffies! g10881 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:26792 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: 6136 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: 0018:ffffc900038af540 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 1ffff11009608341 RCX: ffff88801f8db980
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc900038af6c0 R08: ffffffff8fa3b537 R09: 1ffffffff1f476a6
R10: dffffc0000000000 R11: fffffbfff1f476a7 R12: ffff88804b041a08
R13: dffffc0000000000 R14: ffff88813663b1c0 R15: 0000000000000000
FS:  000055555e836500(0000) GS:ffff8881a3c11000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7db35056c0 CR3: 000000011433a000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 on_each_cpu_cond_mask+0x3f/0x80
 flush_tlb_mm_range+0x6b1/0x12d0
 dup_mmap+0x15a0/0x1ac0
 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: 0033:0x7f7db2785493
Code: 1f 84 00 00 00 00 00 64 48 8b 04 25 10 00 00 00 45 31 c0 31 d2 31 f6 bf 11 00 20 01 4c 8d 90 d0 02 00 00 b8 38 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 89 c2 85 c0 75 2c 64 48 8b 04 25 10 00 00
RSP: 002b:00007fffb77e11b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f7db2785493
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000001200011
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000001
R10: 000055555e8367d0 R11: 0000000000000246 R12: 0000000000000000
R13: 00000000000927c0 R14: 00000000000141c7 R15: 00007fffb77e1350
 </TASK>
