rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P9060/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=57517, q=1014611 ncpus=2)
task:syz.0.782       state:R  running task     stack:26616 pid:9060  tgid:9060  ppid:5860   task_flags:0x40044c flags:0x00004004
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:unwind_next_frame+0x374/0x2390 arch/x86/kernel/unwind_orc.c:505
Code: ea 48 01 d2 48 01 f2 48 bd 00 00 00 00 00 fc ff df 0f 84 37 01 00 00 4c 8d 62 04 4c 8d 6a 05 4c 89 e0 48 c1 e8 03 0f b6 04 28 <84> c0 0f 85 6d 19 00 00 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 0f
RSP: 0018:ffffc9000ddd6f78 EFLAGS: 00000a03
RAX: 0000000000000000 RBX: ffffffff8ff5d4c8 RCX: ffffffff8ff5d4d0
RDX: ffffffff9070ff8a RSI: ffffffff9070fee8 RDI: ffffffff8c0503a0
RBP: dffffc0000000000 R08: 000000000000001f R09: ffffffff81740d25
R10: ffffc9000ddd7098 R11: ffffffff81ac8160 R12: ffffffff9070ff8e
R13: ffffffff9070ff8f R14: ffffc9000ddd7048 R15: ffffffff8ff5d4cc
 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:56
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:559
 __call_rcu_common kernel/rcu/tree.c:3123 [inline]
 call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3243
 slab_free_hook mm/slub.c:2438 [inline]
 slab_free mm/slub.c:6181 [inline]
 kmem_cache_free+0x4b4/0x690 mm/slub.c:6292
 anon_vma_free mm/rmap.c:136 [inline]
 __put_anon_vma+0x12b/0x2d0 mm/rmap.c:2781
 put_anon_vma include/linux/rmap.h:117 [inline]
 unlink_anon_vmas+0x503/0x670 mm/rmap.c:443
 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]
 ret_from_fork+0x53f/0x870 arch/x86/kernel/process.c:167
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
vkms_vblank_simulate: vblank timer overrun