rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P9686/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=26349, q=427 ncpus=2)
task:syz.2.1036      state:R  running task     stack:27288 pid:9686  tgid:9685  ppid:5812   task_flags:0x40054c flags:0x00404006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0x116f/0x5de0 kernel/sched/core.c:6767
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7090
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:check_kcov_mode kernel/kcov.c:185 [inline]
RIP: 0010:write_comp_data+0x3c/0x90 kernel/kcov.c:246
Code: 8b 05 a8 20 e9 11 a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00 0f 00 75 60 a9 00 00 f0 00 75 59 8b 82 3c 16 00 00 85 c0 74 4f <8b> 82 18 16 00 00 83 f8 03 75 44 48 8b 82 20 16 00 00 8b 92 1c 16
RSP: 0018:ffffc90003b678e8 EFLAGS: 00000246
RAX: 0000000080000000 RBX: 0000000000047fc0 RCX: ffffffff822c2dba
RDX: ffff888034228000 RSI: 000000000007ffff RDI: 0000000000000007
RBP: 0000000000000008 R08: 0000000000000007 R09: 000000000007ffff
R10: 0000000000000008 R11: 0000000000000000 R12: ffffea00011ff000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 __nr_to_section include/linux/mmzone.h:1918 [inline]
 __pfn_to_section include/linux/mmzone.h:2060 [inline]
 lookup_page_ext+0x3a/0x190 mm/page_ext.c:251
 page_ext_get+0x58/0x1a0 mm/page_ext.c:539
 __reset_page_owner+0x2b/0x1a0 mm/page_owner.c:294
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1258 [inline]
 __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2721
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3185
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4203
 taskstats_tgid_alloc kernel/taskstats.c:576 [inline]
 taskstats_exit+0x654/0xbe0 kernel/taskstats.c:615
 do_exit+0x85f/0x2c30 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1102
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
 do_syscall_64+0xda/0x260 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7e57b8e969
RSP: 002b:00007f7e559f6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: 0000000000002af7 RBX: 00007f7e57db5fa0 RCX: 00007f7e57b8e969
RDX: 0000000000000002 RSI: 0000200000000840 RDI: 0000000000000007
RBP: 00007f7e57c10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f7e57db5fa0 R15: 00007ffff7ffc548
 </TASK>