2015-04-06 20:21:07

by Malcolm Priestley

[permalink] [raw]
Subject: [PATCH] staging: vt6655: device_intr check for vif on while loop

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 <[email protected]>
---
drivers/staging/vt6655/device_main.c | 21 ++++++++-------------
1 file changed, 8 insertions(+), 13 deletions(-)

diff --git a/drivers/staging/vt6655/device_main.c b/drivers/staging/vt6655/device_main.c
index 4bb4f8e..5b3de43 100644
--- a/drivers/staging/vt6655/device_main.c
+++ b/drivers/staging/vt6655/device_main.c
@@ -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);

--
2.1.0