Merge branch '100GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/next-queue

Tony Nguyen says:

====================
100GbE Intel Wired LAN Driver Updates 2022-03-03

Jacob Keller says:

This series refactors the ice networking driver VF storage from a simple
static array to a hash table. It also introduces krefs and proper locking
and protection to prevent common use-after-free and concurrency issues.

There are two motivations for this work. First is to make the ice driver
more resilient by preventing a whole class of use-after-free bugs that can
occur around concurrent access to VF structures while removing VFs.

The second is to prepare the ice driver for future virtualization work to
support Scalable IOV, an alternative VF implementation compared to Single
Root IOV. The new VF implementation will allow for more dynamic VF creation
and removal, necessitating a more robust implementation for VF storage that
can't rely on the existing mechanisms to prevent concurrent access
violations.

The first few patches are cleanup and preparatory work needed to make the
conversion to the hash table safe. Following this preparatory work is a
patch to migrate the VF structures and variables to a new sub-structure for
code clarity. Next introduce new interface functions to abstract the VF
storage. Finally, the driver is actually converted to the hash table and
kref implementation.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 8 deletions

diff --git a/drivers/net/ethernet/intel/ice/ice_ethtool.c b/drivers/net/ethernet/intel/ice/ice_ethtool.c
index a3492754d0d3..399625892f9e 100644
--- a/drivers/net/ethernet/intel/ice/ice_ethtool.c
+++ b/drivers/net/ethernet/intel/ice/ice_ethtool.c
@@ -316,16 +316,20 @@ out:
  */
 static bool ice_active_vfs(struct ice_pf *pf)
 {
-	unsigned int i;
-
-	ice_for_each_vf(pf, i) {
-		struct ice_vf *vf = &pf->vf[i];
+	bool active = false;
+	struct ice_vf *vf;
+	unsigned int bkt;
 
-		if (test_bit(ICE_VF_STATE_ACTIVE, vf->vf_states))
-			return true;
+	rcu_read_lock();
+	ice_for_each_vf_rcu(pf, bkt, vf) {
+		if (test_bit(ICE_VF_STATE_ACTIVE, vf->vf_states)) {
+			active = true;
+			break;
+		}
 	}
+	rcu_read_unlock();
 
-	return false;
+	return active;
 }
 
 /**
@@ -1298,7 +1302,7 @@ static int ice_set_priv_flags(struct net_device *netdev, u32 flags)
 	}
 
 	if (test_bit(ICE_FLAG_VF_VLAN_PRUNING, change_flags) &&
-	    pf->num_alloc_vfs) {
+	    ice_has_vfs(pf)) {
 		dev_err(dev, "vf-vlan-pruning: VLAN pruning cannot be changed while VFs are active.\n");
 		/* toggle bit back to previous state */
 		change_bit(ICE_FLAG_VF_VLAN_PRUNING, pf->flags);