rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
	(detected by 0, t=10502 jiffies, g=205921, q=1133)
rcu: All QSes seen, last rcu_preempt kthread activity 10502 (4295108978-4295098476), jiffies_till_next_fqs=1, root ->qsmask 0x0
rcu: rcu_preempt kthread starved for 10502 jiffies! g205921 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->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:R  running task     stack:28696 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4965 [inline]
 __schedule+0xa9a/0x4940 kernel/sched/core.c:6246
 schedule+0xd2/0x260 kernel/sched/core.c:6319
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1966
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2139
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 10683 Comm: syz-executor.0 Not tainted 5.15.0-rc5-next-20211015-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1ae/0x220 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_check_gp_kthread_starvation.cold+0x1fb/0x200 kernel/rcu/tree_stall.h:458
 print_other_cpu_stall kernel/rcu/tree_stall.h:563 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:706 [inline]
 rcu_pending kernel/rcu/tree.c:3889 [inline]
 rcu_sched_clock_irq+0x2125/0x2200 kernel/rcu/tree.c:2608
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:unwind_next_frame+0x1360/0x1ca0 arch/x86/kernel/unwind_orc.c:600
Code: 44 24 20 e9 cf fd ff ff 4c 8b 64 24 60 49 8d 78 02 48 b9 00 00 00 00 00 fc ff df 49 8d 56 50 48 89 f8 48 c1 e8 03 0f b6 34 08 <49> 8d 40 03 49 89 c1 49 c1 e9 03 41 0f b6 0c 09 49 89 f9 41 83 e1
RSP: 0018:ffffc9000305f388 EFLAGS: 00000a02
RAX: 1ffffffff1c2c261 RBX: 1ffff9200060be79 RCX: dffffc0000000000
RDX: ffffc9000305f4b0 RSI: 0000000000000000 RDI: ffffffff8e161308
RBP: 0000000000000001 R08: ffffffff8e161306 R09: 0000000000000001
R10: fffff5200060be99 R11: 0000000000088089 R12: ffffc9000305f8c0
R13: ffffc9000305f4a1 R14: ffffc9000305f460 R15: ffffffff8e16130a
 arch_stack_walk+0x7d/0xe0 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8c/0xc0 kernel/stacktrace.c:122
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free mm/kasan/common.c:328 [inline]
 __kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:1700 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1726
 slab_free mm/slub.c:3491 [inline]
 kfree+0xf6/0x560 mm/slub.c:4539
 tty_free_file drivers/tty/tty_io.c:220 [inline]
 tty_open+0x7e0/0x1000 drivers/tty/tty_io.c:2149
 chrdev_open+0x266/0x770 fs/char_dev.c:414
 do_dentry_open+0x4c8/0x11d0 fs/open.c:822
 do_open fs/namei.c:3428 [inline]
 path_openat+0x1c9a/0x2740 fs/namei.c:3561
 do_filp_open+0x1aa/0x400 fs/namei.c:3588
 do_sys_openat2+0x16d/0x4d0 fs/open.c:1200
 do_sys_open fs/open.c:1216 [inline]
 __do_sys_openat fs/open.c:1232 [inline]
 __se_sys_openat fs/open.c:1227 [inline]
 __x64_sys_openat+0x13f/0x1f0 fs/open.c:1227
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7ff61cde1a39
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 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff61a357188 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007ff61cee4f60 RCX: 00007ff61cde1a39
RDX: 0000000000000802 RSI: 0000000020000840 RDI: ffffffffffffff9c
RBP: 00007ff61ce3bc5f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd8797278f R14: 00007ff61a357300 R15: 0000000000022000
 </TASK>
----------------
Code disassembly (best guess):
   0:	44 24 20             	rex.R and $0x20,%al
   3:	e9 cf fd ff ff       	jmpq   0xfffffdd7
   8:	4c 8b 64 24 60       	mov    0x60(%rsp),%r12
   d:	49 8d 78 02          	lea    0x2(%r8),%rdi
  11:	48 b9 00 00 00 00 00 	movabs $0xdffffc0000000000,%rcx
  18:	fc ff df
  1b:	49 8d 56 50          	lea    0x50(%r14),%rdx
  1f:	48 89 f8             	mov    %rdi,%rax
  22:	48 c1 e8 03          	shr    $0x3,%rax
  26:	0f b6 34 08          	movzbl (%rax,%rcx,1),%esi
* 2a:	49 8d 40 03          	lea    0x3(%r8),%rax <-- trapping instruction
  2e:	49 89 c1             	mov    %rax,%r9
  31:	49 c1 e9 03          	shr    $0x3,%r9
  35:	41 0f b6 0c 09       	movzbl (%r9,%rcx,1),%ecx
  3a:	49 89 f9             	mov    %rdi,%r9
  3d:	41                   	rex.B
  3e:	83                   	.byte 0x83
  3f:	e1                   	.byte 0xe1