diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2025-04-08 12:59:52 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-04-09 17:01:52 -0700 |
| commit | 03df156dd3a6d5992f17682cd5c3b11e5ffdae02 (patch) | |
| tree | bae9c0980d13aaec830ddfc17a5605068db1d6df /net/core/xdp.c | |
| parent | netdev: don't hold rtnl_lock over nl queue info get when possible (diff) | |
| download | linux-03df156dd3a6d5992f17682cd5c3b11e5ffdae02.tar.gz linux-03df156dd3a6d5992f17682cd5c3b11e5ffdae02.zip | |
xdp: double protect netdev->xdp_flags with netdev->lock
Protect xdp_features with netdev->lock. This way pure readers
no longer have to take rtnl_lock to access the field.
This includes calling NETDEV_XDP_FEAT_CHANGE under the lock.
Looks like that's fine for bonding, the only "real" listener,
it's the same as ethtool feature change.
In terms of normal drivers - only GVE need special consideration
(other drivers don't use instance lock or don't support XDP).
It calls xdp_set_features_flag() helper from gve_init_priv() which
in turn is called from gve_reset_recovery() (locked), or prior
to netdev registration. So switch to _locked.
Reviewed-by: Joe Damato <jdamato@fastly.com>
Acked-by: Stanislav Fomichev <sdf@fomichev.me>
Acked-by: Harshitha Ramamurthy <hramamurthy@google.com>
Acked-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://patch.msgid.link/20250408195956.412733-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to '')
| -rw-r--r-- | net/core/xdp.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/net/core/xdp.c b/net/core/xdp.c index f86eedad586a..3cd0db9c9d2d 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -17,6 +17,7 @@ #include <net/page_pool/helpers.h> #include <net/hotdata.h> +#include <net/netdev_lock.h> #include <net/xdp.h> #include <net/xdp_priv.h> /* struct xdp_mem_allocator */ #include <trace/events/xdp.h> @@ -991,17 +992,26 @@ static int __init xdp_metadata_init(void) } late_initcall(xdp_metadata_init); -void xdp_set_features_flag(struct net_device *dev, xdp_features_t val) +void xdp_set_features_flag_locked(struct net_device *dev, xdp_features_t val) { val &= NETDEV_XDP_ACT_MASK; if (dev->xdp_features == val) return; + netdev_assert_locked_or_invisible(dev); dev->xdp_features = val; if (dev->reg_state == NETREG_REGISTERED) call_netdevice_notifiers(NETDEV_XDP_FEAT_CHANGE, dev); } +EXPORT_SYMBOL_GPL(xdp_set_features_flag_locked); + +void xdp_set_features_flag(struct net_device *dev, xdp_features_t val) +{ + netdev_lock(dev); + xdp_set_features_flag_locked(dev, val); + netdev_unlock(dev); +} EXPORT_SYMBOL_GPL(xdp_set_features_flag); void xdp_features_set_redirect_target(struct net_device *dev, bool support_sg) |