b43: Protect sanity check against physical device removal

Fix IRQ mask sanity check for physically pulled device.

Tested-by: Andrew Price <andy@andrewprice.me.uk>
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/net/wireless/b43/main.c b/drivers/net/wireless/b43/main.c
index 130dcd5928b1..86f35827f008 100644
--- a/drivers/net/wireless/b43/main.c
+++ b/drivers/net/wireless/b43/main.c
@@ -3874,6 +3874,7 @@ static struct b43_wldev * b43_wireless_core_stop(struct b43_wldev *dev)
 {
         struct b43_wl *wl = dev->wl;
         struct b43_wldev *orig_dev;
+        u32 mask;
 
 redo:
         if (!dev || b43_status(dev) < B43_STAT_STARTED)
@@ -3920,7 +3921,8 @@ redo:
                         goto redo;
                 return dev;
         }
-        B43_WARN_ON(b43_read32(dev, B43_MMIO_GEN_IRQ_MASK));
+        mask = b43_read32(dev, B43_MMIO_GEN_IRQ_MASK);
+        B43_WARN_ON(mask != 0xFFFFFFFF && mask);
 
         /* Drain the TX queue */
         while (skb_queue_len(&wl->tx_queue))