stmmac: fix sleep inside atomic

We cannot use spinlock when kmalloc is invoked with
GFP_KERNEL flag because it can sleep.
So this patch reviews the usage of spinlock within the
stmmac_resume function avoing this bug.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 5 deletions

diff --git a/drivers/net/stmmac/stmmac_main.c b/drivers/net/stmmac/stmmac_main.c
index bbb7951b9c4c..ea0461eb2dbe 100644
--- a/drivers/net/stmmac/stmmac_main.c
+++ b/drivers/net/stmmac/stmmac_main.c
@@ -1865,15 +1865,15 @@ static int stmmac_resume(struct platform_device *pdev)
         if (!netif_running(dev))
                 return 0;
 
-        spin_lock(&priv->lock);
-
         if (priv->shutdown) {
                 /* Re-open the interface and re-init the MAC/DMA
-                   and the rings. */
+                   and the rings (i.e. on hibernation stage) */
                 stmmac_open(dev);
-                goto out_resume;
+                return 0;
         }
 
+        spin_lock(&priv->lock);
+
         /* Power Down bit, into the PM register, is cleared
          * automatically as soon as a magic packet or a Wake-up frame
          * is received. Anyway, it's better to manually clear
@@ -1901,7 +1901,6 @@ static int stmmac_resume(struct platform_device *pdev)
 
         netif_start_queue(dev);
 
-out_resume:
         spin_unlock(&priv->lock);
         return 0;
 }