diff --git a/Documentation/netlink/specs/psp.yaml b/Documentation/netlink/specs/psp.yaml
index e9c2ee7e28e0..f3266763c325 100644
--- a/Documentation/netlink/specs/psp.yaml
+++ b/Documentation/netlink/specs/psp.yaml
@@ -38,6 +38,8 @@ attribute-sets:
         doc: |
           ifindex of the main netdevice linked to the PSP device,
           or the ifindex to associate with the PSP device.
+          Only reported to the network namespace the main netdevice
+          lives in, an ifindex has no meaning outside of it.
         type: u32
       -
         name: psp-versions-cap
diff --git a/net/psp/psp_nl.c b/net/psp/psp_nl.c
index f91665748dde..b57366b5e032 100644
--- a/net/psp/psp_nl.c
+++ b/net/psp/psp_nl.c
@@ -294,13 +294,16 @@ psp_nl_dev_fill(struct psp_dev *psd, struct sk_buff *rsp,
 		return -EMSGSIZE;
 
 	if (nla_put_u32(rsp, PSP_A_DEV_ID, psd->id) ||
-	    nla_put_u32(rsp, PSP_A_DEV_IFINDEX, psd->main_netdev->ifindex) ||
 	    nla_put_u32(rsp, PSP_A_DEV_PSP_VERSIONS_CAP, psd->caps->versions) ||
 	    nla_put_u32(rsp, PSP_A_DEV_PSP_VERSIONS_ENA, psd->config.versions))
 		goto err_cancel_msg;
 
 	if (cur_net == dev_net(psd->main_netdev)) {
-		/* Primary device - dump assoc list */
+		/* Primary device - report the netdev, dump assoc list. */
+		if (nla_put_u32(rsp, PSP_A_DEV_IFINDEX,
+				psd->main_netdev->ifindex))
+			goto err_cancel_msg;
+
 		err = psp_nl_fill_assoc_dev_list(psd, rsp, cur_net, NULL);
 		if (err)
 			goto err_cancel_msg;