rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	0-...!: (0 ticks this GP) idle=c1e4/1/0x4000000000000000 softirq=41339/41339 fqs=0
rcu: 	(detected by 1, t=10505 jiffies, g=31909, q=187 ncpus=2)
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 10354 Comm: syz.5.1230 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+0x152/0x3e0
Code: 89 64 24 14 45 89 e5 85 c0 0f 84 dd 00 00 00 48 85 ed 0f 84 19 01 00 00 83 7d 24 00 0f 85 ea 01 00 00 8b 45 20 3d 00 00 20 00 <48> 8b 5c 24 08 8b 54 24 14 72 25 89 c1 81 e1 00 00 e0 ff 25 ff ff
RSP: 0018:ffffc90000007818 EFLAGS: 00000083
RAX: 00000000000c4067 RBX: 000000000000000f RCX: 9fc5062c85460b00
RDX: 0000000000010000 RSI: ffff88804b027a98 RDI: ffff8881262f0b68
RBP: ffff8881262f0b68 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff52000000f00 R12: 0000000000000003
R13: 0000000000000003 R14: ffff88804b027a98 R15: ffff8881262f0000
FS:  00007fc2ef7e16c0(0000) GS:ffff8880b8611000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2d20eff8 CR3: 0000000121dfe000 CR4: 00000000000006f0
DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000
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:mtree_range_walk+0x466/0x840
Code: 2f 0f b6 c3 4d 8d 34 c6 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 08 4c 89 f7 e8 2d 1d b1 f6 49 8b 06 <48> 89 44 24 30 e8 20 43 08 00 41 89 c6 31 ff 89 c6 e8 14 fe 4c f6
RSP: 0018:ffffc90007d4f320 EFLAGS: 00000246
RAX: ffff888023843e0c RBX: 0000000000000000 RCX: dffffc0000000000
RDX: ffffc90007e09000 RSI: 00000000000137fe RDI: ffffc90007d4f440
RBP: ffff888107cbab40 R08: ffff8881262f0000 R09: 0000000000000004
R10: 0000000000000003 R11: 0000000000000002 R12: 0000000000000000
R13: 00007fc2ecbf7fff R14: ffff88801fbaee50 R15: ffff88801fbaee00
 mt_find+0x23f/0x5f0
 find_vma+0xe7/0x160
 lock_mm_and_find_vma+0x5f/0x300
 do_user_addr_fault+0x331/0x1390
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
RIP: 0010:rep_movs_alternative+0x75/0x90
Code: 05 c3 cc cc cc cc 48 8b 06 48 89 07 48 8d 47 08 48 83 e0 f8 48 29 f8 48 01 c7 48 01 c6 48 29 c1 48 89 c8 48 c1 e9 03 83 e0 07 <f3> 48 a5 89 c1 85 c9 75 91 c3 cc cc cc cc 48 8d 0c c8 eb 86 cc cc
RSP: 0018:ffffc90007d4f798 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888034068028 RCX: 000000000000055c
RDX: 0000000000000001 RSI: 000020000011d000 RDI: ffff88803406d520
RBP: ffffc90007d4f910 R08: ffff88803406ffff R09: 1ffff1100680dfff
R10: dffffc0000000000 R11: ffffed100680e000 R12: 1ffff92000fa9f77
R13: 0000200000117b08 R14: ffffc90007d4fbc8 R15: 0000000000007fd8
 _copy_from_iter+0x24f/0x1790
 mptcp_sendmsg+0xd6e/0x1970
 __sock_sendmsg+0x19c/0x270
 sock_write_iter+0x258/0x330
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fc2ee98ec29
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:00007fc2ef7e1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007fc2eebd5fa0 RCX: 00007fc2ee98ec29
RDX: 000000011ffffce1 RSI: 0000200000000080 RDI: 0000000000000006
RBP: 00007fc2eea11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fc2eebd6038 R14: 00007fc2eebd5fa0 R15: 00007fff6c14ed68
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10504 jiffies! g31909 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=15990
rcu: rcu_preempt kthread starved for 10505 jiffies! g31909 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>
