From: Michael Buesch <mb@bu3sch.de>
Date: Sat, 17 Jun 2006 13:19:05 +0000 (+0200)
Subject: [PATCH] bcm43xx: workaround init_board vs. IRQ race
X-Git-Tag: v2.6.18-rc1~6^2~27
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a1d79aaaa564abc19b7bf3a024bb371fa7648a15;p=linux-2.6

[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>
---

diff --git a/drivers/net/wireless/bcm43xx/bcm43xx_main.c b/drivers/net/wireless/bcm43xx/bcm43xx_main.c
index d8f5600578..673ab11d92 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();