rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7488/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=45265, q=3388 ncpus=2)
task:syz.6.457       state:R  running task     stack:26648 pid:7488  tgid:7488  ppid:6121   task_flags:0x40044c flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5258 [inline]
 __schedule+0x150e/0x5070 kernel/sched/core.c:6866
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7193
 irqentry_exit+0x5d8/0x660 kernel/entry/common.c:216
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x16c/0x340 kernel/locking/lockdep.c:5872
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 f4 66 25 11 <48> 3b 44 24 58 0f 85 e5 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000ee37078 EFLAGS: 00000206
RAX: ccc50315bfb4ce00 RBX: 0000000000000000 RCX: ccc50315bfb4ce00
RDX: 00000000270d408f RSI: ffffffff8dc92d88 RDI: ffffffff8be246e0
RBP: ffffffff81746f85 R08: ffffffff81746f85 R09: ffffffff8e33f860
R10: ffffc9000ee37238 R11: ffffffff81ade7a0 R12: 0000000000000002
R13: ffffffff8e33f860 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:867 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1195 [inline]
 unwind_next_frame+0xc2/0x23d0 arch/x86/kernel/unwind_orc.c:495
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:57
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556
 slab_free_hook mm/slub.c:2501 [inline]
 slab_free mm/slub.c:6674 [inline]
 kmem_cache_free+0x475/0x620 mm/slub.c:6785
 anon_vma_free mm/rmap.c:136 [inline]
 __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2777
 put_anon_vma include/linux/rmap.h:117 [inline]
 unlink_anon_vmas+0x503/0x670 mm/rmap.c:443
 free_pgtables+0x737/0x9d0 mm/memory.c:414
 exit_mmap+0x431/0xb10 mm/mmap.c:1288
 __mmput+0x118/0x430 kernel/fork.c:1177
 exit_mm+0x1da/0x2c0 kernel/exit.c:581
 do_exit+0x850/0x25b0 kernel/exit.c:959
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1112
 get_signal+0x1285/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x87/0x4f0 kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline]
 do_syscall_64+0x2d0/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcdfe1c2005
RSP: 002b:00007fcdfeffbf80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007fcdfe3e6180 RCX: 00007fcdfe1c2005
RDX: 00007fcdfeffbfc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fcdfe213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007fcdfe3e6218 R14: 00007fcdfe3e6180 R15: 00007ffd6a97d0a8
 </TASK>