From 87925151191b64d9623e63ccf11e517eacc99d7d Mon Sep 17 00:00:00 2001 From: Edward Cree Date: Thu, 27 Jun 2024 16:33:51 +0100 Subject: net: ethtool: add a mutex protecting RSS contexts While this is not needed to serialise the ethtool entry points (which are all under RTNL), drivers may have cause to asynchronously access dev->ethtool->rss_ctx; taking dev->ethtool->rss_lock allows them to do this safely without needing to take the RTNL. Signed-off-by: Edward Cree Reviewed-by: Przemek Kitszel Link: https://patch.msgid.link/7f9c15eb7525bf87af62c275dde3a8570ee8bf0a.1719502240.git.ecree.xilinx@gmail.com Signed-off-by: Jakub Kicinski --- net/core/dev.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/core') diff --git a/net/core/dev.c b/net/core/dev.c index 2daed4464c08..385c4091aa77 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -10338,6 +10338,7 @@ int register_netdevice(struct net_device *dev) /* rss ctx ID 0 is reserved for the default context, start from 1 */ xa_init_flags(&dev->ethtool->rss_ctx, XA_FLAGS_ALLOC1); + mutex_init(&dev->ethtool->rss_lock); spin_lock_init(&dev->addr_list_lock); netdev_set_addr_lockdep_class(dev); @@ -11243,6 +11244,7 @@ static void netdev_rss_contexts_free(struct net_device *dev) struct ethtool_rxfh_context *ctx; unsigned long context; + mutex_lock(&dev->ethtool->rss_lock); xa_for_each(&dev->ethtool->rss_ctx, context, ctx) { struct ethtool_rxfh_param rxfh; @@ -11262,6 +11264,7 @@ static void netdev_rss_contexts_free(struct net_device *dev) kfree(ctx); } xa_destroy(&dev->ethtool->rss_ctx); + mutex_unlock(&dev->ethtool->rss_lock); } /** @@ -11374,6 +11377,8 @@ void unregister_netdevice_many_notify(struct list_head *head, if (dev->netdev_ops->ndo_uninit) dev->netdev_ops->ndo_uninit(dev); + mutex_destroy(&dev->ethtool->rss_lock); + if (skb) rtmsg_ifinfo_send(skb, dev, GFP_KERNEL, portid, nlh); -- cgit v1.2.3