ath10k: add accounting for the extended peer statistics

The 10.4 firmware adds extended peer information to the
firmware's statistics payload. This additional info is
stored as a separate data field and the elements are
stored in their own "peers_extd" list.

These elements can pile up in the same way as the peer
information elements. This is because the
ath10k_wmi_10_4_op_pull_fw_stats() function tries to
pull the same amount (num_peer_stats) for every statistic
data unit.

Fixes: 4a49ae94a448faa ("ath10k: fix 10.4 extended peer stats update")
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>

drivers/net/wireless/ath/ath10k/debug.c

@@ -400,6 +400,7 @@ void ath10k_debug_fw_stats_process(struct ath10k *ar, struct sk_buff *skb)
 			 * prevent firmware from DoS-ing the host.
 			 */
 			ath10k_fw_stats_peers_free(&ar->debug.fw_stats.peers);
+			ath10k_fw_extd_stats_peers_free(&ar->debug.fw_stats.peers_extd);
 			ath10k_warn(ar, "dropping fw peer stats\n");
 			goto free;
 		}
@@ -410,10 +411,12 @@ void ath10k_debug_fw_stats_process(struct ath10k *ar, struct sk_buff *skb)
 			goto free;
 		}
 
+		if (!list_empty(&stats.peers))
+			list_splice_tail_init(&stats.peers_extd,
+					      &ar->debug.fw_stats.peers_extd);
+
 		list_splice_tail_init(&stats.peers, &ar->debug.fw_stats.peers);
 		list_splice_tail_init(&stats.vdevs, &ar->debug.fw_stats.vdevs);
-		list_splice_tail_init(&stats.peers_extd,
-				      &ar->debug.fw_stats.peers_extd);
 	}
 
 	complete(&ar->debug.fw_stats_complete);