rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P2176/1:b..l
rcu: 	(detected by 1, t=10503 jiffies, g=70617, q=1135 ncpus=2)
task:kworker/1:2     state:R  running task     stack:20928 pid:2176  tgid:2176  ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events ovs_dp_masks_rebalance
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5354 [inline]
 __schedule+0x165c/0x5520 kernel/sched/core.c:6966
 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7294
 irqentry_exit+0x5e4/0x700 kernel/entry/common.c:240
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:orc_find arch/x86/kernel/unwind_orc.c:228 [inline]
RIP: 0010:unwind_next_frame+0x201/0x2550 arch/x86/kernel/unwind_orc.c:510
Code: 05 01 00 00 48 c7 c0 00 00 00 81 4d 89 e7 49 29 c7 49 c1 ef 08 8b 15 5e 19 c5 0c 8d 42 ff 44 39 f8 0f 86 73 04 00 00 44 89 f8 <4c> 8d 2c 85 b8 04 77 91 4c 89 e8 48 c1 e8 03 0f b6 04 28 84 c0 48
RSP: 0018:ffffc900066f7418 EFLAGS: 00000212
RAX: 000000000000778c RBX: 0000000000000001 RCX: 0000000080000000
RDX: 00000000000abe43 RSI: ffffffff8c2a9240 RDI: ffffffff8c2a9200
RBP: dffffc0000000000 R08: ffffffff81776256 R09: ffffffff8e95d260
R10: ffffc900066f7548 R11: fffff52000cdeeb5 R12: ffffffff81778cd6
R13: 1ffff92000cdeea9 R14: ffffc900066f7548 R15: 000000000000778c
 __unwind_start+0x5b8/0x760 arch/x86/kernel/unwind_orc.c:787
 unwind_start arch/x86/include/asm/unwind.h:64 [inline]
 arch_stack_walk+0xe3/0x150 arch/x86/kernel/stacktrace.c:24
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 save_stack+0x122/0x230 mm/page_owner.c:165
 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 __free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943
 __slab_free+0x274/0x2c0 mm/slub.c:5605
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x99/0x100 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:5292 [inline]
 __kmalloc_noprof+0x35c/0x760 mm/slub.c:5304
 kmalloc_noprof include/linux/slab.h:954 [inline]
 ovs_flow_masks_rebalance+0xf9/0xc30 net/openvswitch/flow_table.c:1112
 ovs_dp_masks_rebalance+0x56/0xe0 net/openvswitch/datapath.c:2562
 process_one_work kernel/workqueue.c:3302 [inline]
 process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
 kthread+0x388/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>