staging: vt6655: device_intr check for vif on while loop
authorMalcolm Priestley <tvboxspy@gmail.com>
Mon, 6 Apr 2015 20:19:48 +0000 (21:19 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 30 Apr 2015 14:57:32 +0000 (16:57 +0200)
vif should never be or go null while in loop.

Fixes race condition where interrupts are late and when
interface is not present.

Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/staging/vt6655/device_main.c

index 4bb4f8e..5b3de43 100644 (file)
@@ -1090,7 +1090,7 @@ static  irqreturn_t  device_intr(int irq,  void *dev_instance)
         * update ISR counter
         */
        STAvUpdate802_11Counter(&pDevice->s802_11Counter, &pDevice->scStatistic, dwMIBCounter);
-       while (pDevice->dwIsr != 0) {
+       while (pDevice->dwIsr && pDevice->vif) {
                STAvUpdateIsrStatCounter(&pDevice->scStatistic, pDevice->dwIsr);
                MACvWriteISR(pDevice->PortOffset, pDevice->dwIsr);
 
@@ -1102,8 +1102,7 @@ static  irqreturn_t  device_intr(int irq,  void *dev_instance)
                }
 
                if (pDevice->dwIsr & ISR_TBTT) {
-                       if (pDevice->vif &&
-                           pDevice->op_mode != NL80211_IFTYPE_ADHOC)
+                       if (pDevice->op_mode != NL80211_IFTYPE_ADHOC)
                                vnt_check_bb_vga(pDevice);
 
                        pDevice->bBeaconSent = false;
@@ -1143,19 +1142,15 @@ static  irqreturn_t  device_intr(int irq,  void *dev_instance)
                        max_count += device_tx_srv(pDevice, TYPE_AC0DMA);
 
                if (pDevice->dwIsr & ISR_SOFTTIMER1) {
-                       if (pDevice->vif) {
-                               if (pDevice->vif->bss_conf.enable_beacon)
-                                       vnt_beacon_make(pDevice, pDevice->vif);
-                       }
+                       if (pDevice->vif->bss_conf.enable_beacon)
+                               vnt_beacon_make(pDevice, pDevice->vif);
                }
 
                /* If both buffers available wake the queue */
-               if (pDevice->vif) {
-                       if (AVAIL_TD(pDevice, TYPE_TXDMA0) &&
-                           AVAIL_TD(pDevice, TYPE_AC0DMA) &&
-                           ieee80211_queue_stopped(pDevice->hw, 0))
-                               ieee80211_wake_queues(pDevice->hw);
-               }
+               if (AVAIL_TD(pDevice, TYPE_TXDMA0) &&
+                   AVAIL_TD(pDevice, TYPE_AC0DMA) &&
+                   ieee80211_queue_stopped(pDevice->hw, 0))
+                       ieee80211_wake_queues(pDevice->hw);
 
                MACvReadISR(pDevice->PortOffset, &pDevice->dwIsr);