i40e: acquire VSI pointer only after VF is initialized

This change simplifies the VF initialization check and also minimizes
the delay between acquiring the VSI pointer and using it. As known by
the commit being fixed, there is a risk of the VSI pointer getting
changed. Therefore minimize the delay between getting and using the
pointer.

Fixes: 9889707b06ac ("i40e: Fix crash caused by stress setting of VF MAC addresses")
Signed-off-by: Stefan Assmann <sassmann@kpanic.de>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Konrad Jankowski <konrad0.jankowski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
index 21ee56420c3aee60f1428ebf2566611addd34c04..7efc61aacb0a5441dfc55e47af32596d3541fbc2 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -4046,20 +4046,16 @@ int i40e_ndo_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
                goto error_param;
 
        vf = &pf->vf[vf_id];
-       vsi = pf->vsi[vf->lan_vsi_idx];
 
        /* When the VF is resetting wait until it is done.
         * It can take up to 200 milliseconds,
         * but wait for up to 300 milliseconds to be safe.
-        * If the VF is indeed in reset, the vsi pointer has
-        * to show on the newly loaded vsi under pf->vsi[id].
+        * Acquire the VSI pointer only after the VF has been
+        * properly initialized.
         */
        for (i = 0; i < 15; i++) {
-               if (test_bit(I40E_VF_STATE_INIT, &vf->vf_states)) {
-                       if (i > 0)
-                               vsi = pf->vsi[vf->lan_vsi_idx];
+               if (test_bit(I40E_VF_STATE_INIT, &vf->vf_states))
                        break;
-               }
                msleep(20);
        }
        if (!test_bit(I40E_VF_STATE_INIT, &vf->vf_states)) {
@@ -4068,6 +4064,7 @@ int i40e_ndo_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
                ret = -EAGAIN;
                goto error_param;
        }
+       vsi = pf->vsi[vf->lan_vsi_idx];
 
        if (is_multicast_ether_addr(mac)) {
                dev_err(&pf->pdev->dev,