netfilter: flowtable: Make sure GC works periodically in idle system

stable inclusion
from stable-5.10.27
commit 4280132339ce99b6521216d8b8e56b1bb462189e
bugzilla: 51493

--------------------------------

[ Upstream commit 740b486a ]

Currently flowtable's GC work is initialized as deferrable, which
means GC cannot work on time when system is idle. So the hardware
offloaded flow may be deleted for timeout, since its used time is
not timely updated.

Resolve it by initializing the GC work as delayed work instead of
deferrable.

Fixes: c29f74e0 ("netfilter: nf_flow_table: hardware offload support")
Signed-off-by: NYinjun Zhang <yinjun.zhang@corigine.com>
Signed-off-by: NLouis Peens <louis.peens@corigine.com>
Signed-off-by: NSimon Horman <simon.horman@netronome.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NSasha Levin <sashal@kernel.org>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Acked-by: N  Weilong Chen <chenweilong@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

net/netfilter/nf_flow_table_core.c

@@ -506,7 +506,7 @@ int nf_flow_table_init(struct nf_flowtable *flowtable)
 {
 	int err;
 
-	INIT_DEFERRABLE_WORK(&flowtable->gc_work, nf_flow_offload_work_gc);
+	INIT_DELAYED_WORK(&flowtable->gc_work, nf_flow_offload_work_gc);
 	flow_block_init(&flowtable->flow_block);
 	init_rwsem(&flowtable->flow_block_lock);