FAILED: patch "[PATCH] i40e: Fix NULL pointer dereference in i40e_dbg_dump_desc" failed to apply to 4.19-stable tree

The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 23ec111bf3549aae37140330c31a16abfc172421 Mon Sep 17 00:00:00 2001
From: Norbert Zulinski <[email protected]>
Date: Mon, 22 Nov 2021 12:29:05 +0100
Subject: [PATCH] i40e: Fix NULL pointer dereference in i40e_dbg_dump_desc

When trying to dump VFs VSI RX/TX descriptors using debugfs there was a crash
due to NULL pointer dereference in i40e_dbg_dump_desc. Added a check to i40e_dbg_dump_desc that checks if VSI type is correct for dumping RX/TX descriptors.

index 291e61ac3e44..2c1b1da1220e 100644
@@ -553,6 +553,14 @@ static void i40e_dbg_dump_desc(int cnt, int vsi_seid, int ring_id, int desc_n,
 		dev_info(&pf->pdev->dev, "vsi %d not found\n", vsi_seid);
 		return;
 	}
+	if (vsi->type != I40E_VSI_MAIN &&
+	    vsi->type != I40E_VSI_FDIR &&
+	    vsi->type != I40E_VSI_VMDQ2) {
+		dev_info(&pf->pdev->dev,
+			 "vsi %d type %d descriptor rings not available\n",
+			 vsi_seid, vsi->type);
+		return;
+	}
 	if (type == RING_TYPE_XDP && !i40e_enabled_xdp_vsi(vsi)) {
 		dev_info(&pf->pdev->dev, "XDP not enabled on VSI %d\n", vsi_seid);
 		return;