[PATCH] bcm43xx: workaround init_board vs. IRQ race

Place the Init-vs-IRQ workaround before any card register
access, because we might not have the wireless core mapped
at all times in init. So this will result in a Machine Check
caused by a bus error.

Signed-off-by: Michael Buesch <mb@bu3sch.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 14 insertions, 13 deletions

diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_main.c b/drivers/net/wireless/bcm43xx/bcm43xx_main.c
index d8f5600578b4..673ab11d92ab 100644
--- a/drivers/net/wireless/bcm43xx/bcm43xx_main.c
+++ b/drivers/net/wireless/bcm43xx/bcm43xx_main.c
@@ -1885,6 +1885,15 @@ static irqreturn_t bcm43xx_interrupt_handler(int irq, void *dev_id, struct pt_re
 
         spin_lock(&bcm->irq_lock);
 
+        /* Only accept IRQs, if we are initialized properly.
+         * This avoids an RX race while initializing.
+         * We should probably not enable IRQs before we are initialized
+         * completely, but some careful work is needed to fix this. I think it
+         * is best to stay with this cheap workaround for now... .
+         */
+        if (unlikely(bcm43xx_status(bcm) != BCM43xx_STAT_INITIALIZED))
+                goto out;
+
         reason = bcm43xx_read32(bcm, BCM43xx_MMIO_GEN_IRQ_REASON);
         if (reason == 0xffffffff) {
                 /* irq not for us (shared irq) */
@@ -1906,19 +1915,11 @@ static irqreturn_t bcm43xx_interrupt_handler(int irq, void *dev_id, struct pt_re
 
         bcm43xx_interrupt_ack(bcm, reason);
 
-        /* Only accept IRQs, if we are initialized properly.
-         * This avoids an RX race while initializing.
-         * We should probably not enable IRQs before we are initialized
-         * completely, but some careful work is needed to fix this. I think it
-         * is best to stay with this cheap workaround for now... .
-         */
-        if (likely(bcm43xx_status(bcm) == BCM43xx_STAT_INITIALIZED)) {
-                /* disable all IRQs. They are enabled again in the bottom half. */
-                bcm->irq_savedstate = bcm43xx_interrupt_disable(bcm, BCM43xx_IRQ_ALL);
-                /* save the reason code and call our bottom half. */
-                bcm->irq_reason = reason;
-                tasklet_schedule(&bcm->isr_tasklet);
-        }
+        /* disable all IRQs. They are enabled again in the bottom half. */
+        bcm->irq_savedstate = bcm43xx_interrupt_disable(bcm, BCM43xx_IRQ_ALL);
+        /* save the reason code and call our bottom half. */
+        bcm->irq_reason = reason;
+        tasklet_schedule(&bcm->isr_tasklet);
 
 out:
         mmiowb();