rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P19091/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=91165, q=1599256 ncpus=2)
task:syz.2.4142      state:R  running task     stack:25440 pid:19091 tgid:19091 ppid:19093  task_flags:0x40044c flags:0x01004024
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5360 [inline]
 __schedule+0x1798/0x4cc0 kernel/sched/core.c:6964
 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7291
 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:lock_acquire+0x175/0x360 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 0b 23 26 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc9000428f0b8 EFLAGS: 00000206
RAX: cc13ca57d52d4a00 RBX: 0000000000000000 RCX: cc13ca57d52d4a00
RDX: 0000000000000000 RSI: ffffffff8ddae1af RDI: ffffffff8c036f00
RBP: ffffffff8173bd25 R08: 0000000000000000 R09: ffffffff8173bd25
R10: ffffc9000428f278 R11: ffffffff81ac3160 R12: 0000000000000002
R13: ffffffff8e33c820 R14: 0000000000000000 R15: 0000000000000246
 rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 rcu_read_lock include/linux/rcupdate.h:841 [inline]
 class_rcu_constructor include/linux/rcupdate.h:1169 [inline]
 unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5b/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2474 [inline]
 slab_free mm/slub.c:6181 [inline]
 kmem_cache_free+0x19a/0x690 mm/slub.c:6292
 anon_vma_chain_free mm/rmap.c:146 [inline]
 unlink_anon_vmas+0x614/0x670 mm/rmap.c:446
 free_pgtables+0x72b/0x9c0 mm/memory.c:413
 exit_mmap+0x43c/0xb40 mm/mmap.c:1291
 __mmput+0x118/0x430 kernel/fork.c:1148
 exit_mm+0x1da/0x2c0 kernel/exit.c:582
 do_exit+0x648/0x2300 kernel/exit.c:954
 do_group_exit+0x21c/0x2d0 kernel/exit.c:1107
 get_signal+0x1286/0x1340 kernel/signal.c:3034
 arch_do_signal_or_restart+0x9a/0x750 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x75/0x130 kernel/entry/common.c:40
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f74df7c1465
RSP: 002b:00007f74e05eef80 EFLAGS: 00000393 ORIG_RAX: 00000000000000db
RAX: ffffffffffffffda RBX: 00007f74df9d5fa0 RCX: 00007f74df7c1465
RDX: 00007f74e05eefc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f74df811e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000393 R12: 0000000000000000
R13: 00007f74df9d6038 R14: 00007f74df9d5fa0 R15: 00007ffd10bd55b8
 </TASK>