Re: Linux 2.6.17.1

Michael Buesch
2006-06-20T10:36:16Z

On Tuesday 20 June 2006 12:13, Chris Wright wrote:
> We (the -stable team) are announcing the release of the 2.6.17.1 kernel.

Please consider inclusion of the following patch into 2.6.17.2:

It fixes a possible crash. Might be triggerable in networks with
heavy traffic. I only saw it once so far, though.

--

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>

Index: tmp/drivers/net/wireless/bcm43xx/bcm43xx_main.c
===================================================================
--- tmp.orig/drivers/net/wireless/bcm43xx/bcm43xx_main.c 2006-06-18 18:51:48.000000000 +0200
+++ tmp/drivers/net/wireless/bcm43xx/bcm43xx_main.c 2006-06-18 19:02:19.000000000 +0200
@@ -1870,6 +1870,15 @@

spin_lock(&bcm->_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(!bcm->initialized))
+ goto out;
+
reason = bcm43xx_read32(bcm, BCM43xx_MMIO_GEN_IRQ_REASON);
if (reason == 0xffffffff) {
/* irq not for us (shared irq) */
@@ -1891,20 +1900,11 @@

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(bcm->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();
spin_unlock(&bcm->_lock);

--
Greetings Michael.