syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P11775/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=41037, q=841 ncpus=2)
task:syz.8.1306      state:R  running task     stack:28184 pid:11775 tgid:11774 ppid:10359  task_flags:0x400140 flags:0x00004002
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:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5870
Code: fe 0b 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 42 f3 ec 0e 0f 82 74 02 00 00 8b 35 da 22 ed 0e 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 19 fe 0b 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc90004edf858 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e3bf5c0 RCX: 00000000c51d0e44
RDX: 0000000000000000 RSI: ffffffff8dbbbc2f RDI: ffffffff8bf48260
RBP: 0000000000000002 R08: edd8168bcfa0d69c R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 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:1155 [inline]
 unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479
 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x8e/0xc0 kernel/stacktrace.c:122
 save_stack+0x160/0x1f0 mm/page_owner.c:156
 __reset_page_owner+0x84/0x1a0 mm/page_owner.c:308
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x69d/0xff0 mm/page_alloc.c:2725
 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]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_noprof+0x1d4/0x510 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 cgroup_create kernel/cgroup/cgroup.c:5720 [inline]
 cgroup_mkdir+0x2a4/0x1160 kernel/cgroup/cgroup.c:5870
 kernfs_iop_mkdir+0x108/0x190 fs/kernfs/dir.c:1266
 vfs_mkdir+0x590/0x8c0 fs/namei.c:4359
 do_mkdirat+0x304/0x3e0 fs/namei.c:4392
 __do_sys_mkdirat fs/namei.c:4409 [inline]
 __se_sys_mkdirat fs/namei.c:4407 [inline]
 __x64_sys_mkdirat+0x83/0xb0 fs/namei.c:4407
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9144f8e969
RSP: 002b:00007f9145ea5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f91451b5fa0 RCX: 00007f9144f8e969
RDX: 00000000000001ff RSI: 0000200000000040 RDI: ffffffffffffff9c
RBP: 00007f9145010ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f91451b5fa0 R15: 00007fffe461baf8
 </TASK>