On 9/22/17 12:10 AM, Florian Westphal wrote:
> Switch it to rcu.
>
> rtnl_link_slave_info_fill on to other hand does need rtnl mutex for now so
> add an annotation to its caller as a reminder.
>
> Signed-off-by: Florian Westphal <f...@strlen.de>
> ---
> Change since v1:
> - don't add ASSERT_RTNL to rtnl_link_slave_info_fill and
> rtnl_link_info_fill they are only called via rtnl_link_fill.
>
> net/core/rtnetlink.c | 12 +++++++++---
> 1 file changed, 9 insertions(+), 3 deletions(-)
>
> diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
> index 590823f70cc3..e6f9e36d9d5a 100644
> --- a/net/core/rtnetlink.c
> +++ b/net/core/rtnetlink.c
> @@ -522,11 +522,15 @@ static size_t rtnl_link_get_af_size(const struct
> net_device *dev,
> static bool rtnl_have_link_slave_info(const struct net_device *dev)
> {
> struct net_device *master_dev;
> + bool ret = false;
>
> - master_dev = netdev_master_upper_dev_get((struct net_device *) dev);
> + rcu_read_lock();
> +
> + master_dev = netdev_master_upper_dev_get_rcu((struct net_device *)dev);
> if (master_dev && master_dev->rtnl_link_ops)
> - return true;
> - return false;
> + ret = true;
> + rcu_read_unlock();
> + return ret;
> }
>
> static int rtnl_link_slave_info_fill(struct sk_buff *skb,
> @@ -598,6 +602,8 @@ static int rtnl_link_fill(struct sk_buff *skb, const
> struct net_device *dev)
> struct nlattr *linkinfo;
> int err = -EMSGSIZE;
>
> + ASSERT_RTNL();
Rather than sprinkling the ASSERT_RTNL why not just add a comment above
the function which is done in many places. Since this is really meant as
your notes as you remove rtnl usage a comment serves the same purpose.
> +
> linkinfo = nla_nest_start(skb, IFLA_LINKINFO);
> if (linkinfo == NULL)
> goto out;
>
Reviewed-by: David Ahern <dsah...@gmail.com>
