From: Jussi Maki <joamaki@gmail.com>
Date: Sat, 31 Jul 2021 05:57:36 +0000
Subject: net, core: Allow netdev_lower_get_next_private_rcu in bh context
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Patch-mainline: v5.15-rc1
Git-commit: 689186699931313c7a42462602bd5c03eef77f9f
References: jsc#PED-1377

For the XDP bonding slave lookup to work in the NAPI poll context in which
the redudant rcu_read_lock() has been removed we have to follow the same
approach as in 694cea395fde ("bpf: Allow RCU-protected lookups to happen
from bh context") and modify the WARN_ON to also check rcu_read_lock_bh_held().

Signed-off-by: Jussi Maki <joamaki@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20210731055738.16820-6-joamaki@gmail.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 net/core/dev.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -7534,7 +7534,7 @@ void *netdev_lower_get_next_private_rcu(
 {
 	struct netdev_adjacent *lower;
 
-	WARN_ON_ONCE(!rcu_read_lock_held());
+	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
 
 	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);