[PATCH net] net: stmmac: fix invalid usage of irq_set_affinity_hint

[Qingfang DENG]

The cpumask should not be a local variable, since its pointer is saved
to irq_desc and may be accessed from procfs.
To fix it, store cpumask to the heap.

Fixes: 8deec94c6040 ("net: stmmac: set IRQ affinity hint for multi MSI vectors")
Signed-off-by: Qingfang DENG <dqfext at gmail.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac.h      |  2 ++
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c | 15 ++++++++-------
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac.h b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
index bdbf86cb102a..720e9f2a40d8 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac.h
@@ -77,6 +77,7 @@ struct stmmac_tx_queue {
 	dma_addr_t dma_tx_phy;
 	dma_addr_t tx_tail_addr;
 	u32 mss;
+	cpumask_t cpu_mask;
 };
 
 struct stmmac_rx_buffer {
@@ -114,6 +115,7 @@ struct stmmac_rx_queue {
 		unsigned int len;
 		unsigned int error;
 	} state;
+	cpumask_t cpu_mask;
 };
 
 struct stmmac_channel {
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 8418e795cc21..7b1c1be998e3 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -3469,7 +3469,6 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
 {
 	struct stmmac_priv *priv = netdev_priv(dev);
 	enum request_irq_err irq_err;
-	cpumask_t cpu_mask;
 	int irq_idx = 0;
 	char *int_name;
 	int ret;
@@ -3580,9 +3579,10 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
 			irq_idx = i;
 			goto irq_error;
 		}
-		cpumask_clear(&cpu_mask);
-		cpumask_set_cpu(i % num_online_cpus(), &cpu_mask);
-		irq_set_affinity_hint(priv->rx_irq[i], &cpu_mask);
+		cpumask_set_cpu(i % num_online_cpus(),
+				&priv->dma_conf.rx_queue[i].cpu_mask);
+		irq_set_affinity_hint(priv->rx_irq[i],
+				      &priv->dma_conf.rx_queue[i].cpu_mask);
 	}
 
 	/* Request Tx MSI irq */
@@ -3605,9 +3605,10 @@ static int stmmac_request_irq_multi_msi(struct net_device *dev)
 			irq_idx = i;
 			goto irq_error;
 		}
-		cpumask_clear(&cpu_mask);
-		cpumask_set_cpu(i % num_online_cpus(), &cpu_mask);
-		irq_set_affinity_hint(priv->tx_irq[i], &cpu_mask);
+		cpumask_set_cpu(i % num_online_cpus(),
+				&priv->dma_conf.tx_queue[i].cpu_mask);
+		irq_set_affinity_hint(priv->tx_irq[i],
+				      &priv->dma_conf.tx_queue[i].cpu_mask);
 	}
 
 	return 0;
-- 
2.34.1