Commit a14fbcd4 authored May 14, 2020 by Amol Grover Committed by David S. Miller May 14, 2020

ipmr: Fix RCU list debugging warning



ipmr_for_each_table() macro uses list_for_each_entry_rcu()
for traversing outside of an RCU read side critical section
but under the protection of rtnl_mutex. Hence, add the
corresponding lockdep expression to silence the following
false-positive warning at boot:

[    4.319347] =============================
[    4.319349] WARNING: suspicious RCU usage
[    4.319351] 5.5.4-stable #17 Tainted: G            E
[    4.319352] -----------------------------
[    4.319354] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!!

Fixes: f0ad0860 ("ipv4: ipmr: support multiple tables")
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent 95f59bf8

net/ipv4/ipmr.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -110,7 +110,8 @@ static void ipmr_expire_process(struct timer_list *t);

		#ifdef CONFIG_IP_MROUTE_MULTIPLE_TABLES
		#define ipmr_for_each_table(mrt, net) \
		list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list)
		list_for_each_entry_rcu(mrt, &net->ipv4.mr_tables, list, \
		lockdep_rtnl_is_held())

		static struct mr_table ipmr_mr_table_iter(struct net net,
		struct mr_table *mrt)

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