From: Stefan Assmann <sassmann@kpanic.de>
Date: Mon, 30 Nov 2020 14:12:57 +0100
Subject: i40e: acquire VSI pointer only after VF is initialized
Patch-mainline: v5.11-rc6
Git-commit: 67a3c6b3cc40bb217c3ff947a55053151a00fea0
References: jsc#SLE-8025

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>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c |   11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
@@ -3969,20 +3969,16 @@ int i40e_ndo_set_vf_mac(struct net_devic
 		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)) {
@@ -3991,6 +3987,7 @@ int i40e_ndo_set_vf_mac(struct net_devic
 		ret = -EAGAIN;
 		goto error_param;
 	}
+	vsi = pf->vsi[vf->lan_vsi_idx];
 
 	if (is_multicast_ether_addr(mac)) {
 		dev_err(&pf->pdev->dev,