[PATCH net] ethtool: mark netlink policy as __ro_after_init

[PATCH net] ethtool: mark netlink policy as __ro_after_init

[Jakub Kicinski]

Like all genl families ethtool_genl_family needs to not
be a straight up constant, because it's modified/initialized
by genl_register_family(). After init, however, it's only
passed to genlmsg_put() & co. therefore we can mark it
as __ro_after_init.

Since genl_family structure contains function pointers
mark this as a fix.

Fixes: 2b4a8990b7df ("ethtool: introduce ethtool netlink interface")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 net/ethtool/netlink.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 5c2072765be7..0c3f54baec4e 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -866,7 +866,7 @@ static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
 	[ETHNL_MCGRP_MONITOR] = { .name = ETHTOOL_MCGRP_MONITOR_NAME },
 };
 
-static struct genl_family ethtool_genl_family = {
+static struct genl_family ethtool_genl_family __ro_after_init = {
 	.name		= ETHTOOL_GENL_NAME,
 	.version	= ETHTOOL_GENL_VERSION,
 	.netnsok	= true,
-- 
2.26.2

Re: [PATCH net] ethtool: mark netlink policy as __ro_after_init

[Jakub Kicinski]

On Mon, 28 Sep 2020 17:57:18 -0700 Jakub Kicinski wrote:
> Like all genl families ethtool_genl_family needs to not
> be a straight up constant, because it's modified/initialized
> by genl_register_family(). After init, however, it's only
> passed to genlmsg_put() & co. therefore we can mark it
> as __ro_after_init.

Sorry I just realized the subject is off.