syzbot

rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P7173/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=27005, q=168109 ncpus=2)
task:udevd           state:R  running task     stack:26856 pid:7173  tgid:7173  ppid:5200   task_flags:0x400140 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5397 [inline]
 __schedule+0x116a/0x5dd0 kernel/sched/core.c:6786
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:7109
 irqentry_exit+0x36/0x90 kernel/entry/common.c:307
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:lock_acquire+0x62/0x350 kernel/locking/lockdep.c:5875
Code: 76 37 12 83 f8 07 0f 87 bc 02 00 00 89 c0 48 0f a3 05 32 b6 10 0f 0f 82 74 02 00 00 8b 35 1a e8 10 0f 85 f6 0f 85 8d 00 00 00 <48> 8b 44 24 30 65 48 2b 05 c9 75 37 12 0f 85 c7 02 00 00 48 83 c4
RSP: 0018:ffffc900030b7748 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffffffff8e5c4e00 RCX: 000000006481f9f7
RDX: 0000000000000000 RSI: ffffffff8de0adb5 RDI: ffffffff8c157460
RBP: 0000000000000002 R08: 9e0ff3f8210f2cbc R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 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:1248 [inline]
 __free_frozen_pages+0x7fe/0x1180 mm/page_alloc.c:2706
 discard_slab mm/slub.c:2717 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3186
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/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:4148 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4204
 getname_flags.part.0+0x4c/0x550 fs/namei.c:146
 getname_flags+0x93/0xf0 include/linux/audit.h:322
 getname include/linux/fs.h:2907 [inline]
 getname_maybe_null include/linux/fs.h:2914 [inline]
 getname_maybe_null include/linux/fs.h:2911 [inline]
 path_setxattrat+0x27a/0x2a0 fs/xattr.c:705
 __do_sys_lsetxattr fs/xattr.c:754 [inline]
 __se_sys_lsetxattr fs/xattr.c:750 [inline]
 __x64_sys_lsetxattr+0xc9/0x140 fs/xattr.c:750
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f561191d57a
RSP: 002b:00007ffd1a0911a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00005584e4267700 RCX: 00007f561191d57a
RDX: 00005584e4267700 RSI: 00007f561202929c RDI: 00007ffd1a091cf0
RBP: 00005584e40258d0 R08: 0000000000000000 R09: 00005584e402a450
R10: 000000000000001b R11: 0000000000000246 R12: 00007ffd1a091cf0
R13: 0000000000000001 R14: 00005584ac5e86d7 R15: 00005584e4279870
 </TASK>