rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7233/1:b..l P5831/1:b..l
rcu: 	(detected by 0, t=10503 jiffies, g=18765, q=1340354 ncpus=2)
task:syz-executor    state:R  running task     stack:21064 pid:5831  tgid:5831  ppid:5825   task_flags:0x400140 flags:0x00080000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5340 kernel/sched/core.c:6907
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7234
 irqentry_exit+0x599/0x620 kernel/entry/common.c:239
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__page_table_check_zero+0x154/0x3e0 mm/page_table_check.c:-1
Code: c1 fd 06 4c 89 ef e8 7b f4 ff ff 48 85 c0 0f 84 b8 01 00 00 49 89 c7 4c 89 64 24 08 49 ff c5 bf 20 00 00 00 8b 5c 24 04 89 de <e8> 27 9e 89 ff 89 d8 48 89 44 24 10 b8 01 00 00 00 89 d9 d3 e0 48
RSP: 0018:ffffc90003947778 EFLAGS: 00000202
RAX: ffff88801ee6c960 RBX: 0000000000000001 RCX: ffff88807ecf1e40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000020
RBP: dffffc0000000000 R08: ffffffff823c087a R09: ffffffff8e7602e0
R10: dffffc0000000000 R11: ffffed1006d3cf26 R12: ffffffff823c087a
R13: 0000000000077c1f R14: 0000000000000000 R15: ffff88801ee6c960
 page_table_check_free include/linux/page_table_check.h:46 [inline]
 __free_pages_prepare mm/page_alloc.c:1434 [inline]
 __free_frozen_pages+0xc3b/0xdb0 mm/page_alloc.c:2978
 __slab_free+0x263/0x2b0 mm/slub.c:5532
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5219 [inline]
 __kmalloc_noprof+0x35c/0x760 mm/slub.c:5231
 kmalloc_noprof include/linux/slab.h:966 [inline]
 kzalloc_noprof include/linux/slab.h:1204 [inline]
 tomoyo_encode2 security/tomoyo/realpath.c:45 [inline]
 tomoyo_encode+0x28b/0x550 security/tomoyo/realpath.c:80
 tomoyo_realpath_from_path+0x58d/0x5d0 security/tomoyo/realpath.c:283
 tomoyo_get_realpath security/tomoyo/file.c:151 [inline]
 tomoyo_path_perm+0x283/0x560 security/tomoyo/file.c:827
 security_inode_getattr+0x12b/0x310 security/security.c:1869
 vfs_getattr fs/stat.c:259 [inline]
 vfs_fstat fs/stat.c:281 [inline]
 __do_sys_newfstat fs/stat.c:551 [inline]
 __se_sys_newfstat fs/stat.c:546 [inline]
 __x64_sys_newfstat+0x13b/0x270 fs/stat.c:546
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f0e6799aca7
RSP: 002b:00007ffdcdafd618 EFLAGS: 00000206 ORIG_RAX: 0000000000000005
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f0e6799aca7
RDX: 0000000000000000 RSI: 00007ffdcdafd620 RDI: 0000000000000003
RBP: 00007ffdcdafe80c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 00007ffdcdafe820
R13: 00007f0e67a31ef0 R14: 00000000000339cc R15: 00007ffdcdafe860
 </TASK>
task:syz.4.305       state:R  running task     stack:24352 pid:7233  tgid:7233  ppid:5829   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0x1585/0x5340 kernel/sched/core.c:6907
 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:7091
 preempt_schedule_thunk+0x16/0x30 arch/x86/entry/thunk.S:12
 __raw_spin_unlock include/linux/spinlock_api_smp.h:169 [inline]
 _raw_spin_unlock+0x3f/0x50 kernel/locking/spinlock.c:186
 spin_unlock include/linux/spinlock.h:389 [inline]
 insert_page mm/memory.c:2398 [inline]
 vm_insert_page+0x458/0x620 mm/memory.c:2547
 kcov_mmap+0xc9/0x140 kernel/kcov.c:514
 vfs_mmap include/linux/fs.h:2070 [inline]
 mmap_file mm/internal.h:167 [inline]
 __mmap_new_file_vma mm/vma.c:2468 [inline]
 __mmap_new_vma mm/vma.c:2532 [inline]
 __mmap_region mm/vma.c:2759 [inline]
 mmap_region+0x18fe/0x2240 mm/vma.c:2837
 do_mmap+0xc39/0x10c0 mm/mmap.c:559
 vm_mmap_pgoff+0x2c9/0x4f0 mm/util.c:581
 ksys_mmap_pgoff+0x51e/0x760 mm/mmap.c:605
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f59c899c392
RSP: 002b:00007fff9819b7f8 EFLAGS: 00000206 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f59c5ff2000 RCX: 00007f59c899c392
RDX: 0000000000000003 RSI: 0000000000400000 RDI: 00007f59c5ff2000
RBP: 0000000000000011 R08: 00000000000000dd R09: 0000000000000000
R10: 0000000000000011 R11: 0000000000000206 R12: 0000000000000003
R13: 0000000000000003 R14: 0000000000000000 R15: 00007f59c8c15fa0
 </TASK>