mvpp2: fix pointer check

priv->page_pool is an array, so comparing against it will always return true.
Do a meaningful check by checking priv->page_pool[0] instead.
While at it, clear the page_pool pointers on deallocation, or when an
allocation error happens during init.

Reported-by: Colin Ian King <colin.king@canonical.com>
Fixes: c2d6fe6163de ("mvpp2: XDP TX support")
Signed-off-by: Matteo Croce <mcroce@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index d8e238e..6a3f356 100644 (file)
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -548,8 +548,10 @@ static int mvpp2_bm_pool_destroy(struct device *dev, struct mvpp2 *priv,
        val |= MVPP2_BM_STOP_MASK;
        mvpp2_write(priv, MVPP2_BM_POOL_CTRL_REG(bm_pool->id), val);
 
-       if (priv->percpu_pools)
+       if (priv->percpu_pools) {
                page_pool_destroy(priv->page_pool[bm_pool->id]);
+               priv->page_pool[bm_pool->id] = NULL;
+       }
 
        dma_free_coherent(dev, bm_pool->size_bytes,
                          bm_pool->virt_addr,
@@ -609,8 +611,15 @@ static int mvpp2_bm_init(struct device *dev, struct mvpp2 *priv)
                                                       mvpp2_pools[pn].buf_num,
                                                       mvpp2_pools[pn].pkt_size,
                                                       dma_dir);
-                       if (IS_ERR(priv->page_pool[i]))
+                       if (IS_ERR(priv->page_pool[i])) {
+                               int j;
+
+                               for (j = 0; j < i; j++) {
+                                       page_pool_destroy(priv->page_pool[j]);
+                                       priv->page_pool[j] = NULL;
+                               }
                                return PTR_ERR(priv->page_pool[i]);
+                       }
                }
        }
 
@@ -4486,7 +4495,7 @@ static int mvpp2_check_pagepool_dma(struct mvpp2_port *port)
        if (!priv->percpu_pools)
                return err;
 
-       if (!priv->page_pool)
+       if (!priv->page_pool[0])
                return -ENOMEM;
 
        for (i = 0; i < priv->port_count; i++) {