hostap: Protect against initialization interrupt
Use an irq spinlock to hold off the IRQ handler until
enough early card init is complete such that the handler
can run without faulting.
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/hostap/hostap_cs.c b/drivers/net/wireless/hostap/hostap_cs.c
index db72461..29b31a6 100644
--- a/drivers/net/wireless/hostap/hostap_cs.c
+++ b/drivers/net/wireless/hostap/hostap_cs.c
@@ -594,6 +594,7 @@
local_info_t *local;
int ret = 1;
struct hostap_cs_priv *hw_priv;
+ unsigned long flags;
PDEBUG(DEBUG_FLOW, "prism2_config()\n");
@@ -625,9 +626,15 @@
local->hw_priv = hw_priv;
hw_priv->link = link;
+ /*
+ * Make sure the IRQ handler cannot proceed until at least
+ * dev->base_addr is initialized.
+ */
+ spin_lock_irqsave(&local->irq_init_lock, flags);
+
ret = pcmcia_request_irq(link, prism2_interrupt);
if (ret)
- goto failed;
+ goto failed_unlock;
/*
* This actually configures the PCMCIA socket -- setting up
@@ -636,11 +643,13 @@
*/
ret = pcmcia_request_configuration(link, &link->conf);
if (ret)
- goto failed;
+ goto failed_unlock;
dev->irq = link->irq;
dev->base_addr = link->io.BasePort1;
+ spin_unlock_irqrestore(&local->irq_init_lock, flags);
+
/* Finally, report what we've done */
printk(KERN_INFO "%s: index 0x%02x: ",
dev_info, link->conf.ConfigIndex);
@@ -667,6 +676,8 @@
return ret;
+ failed_unlock:
+ spin_unlock_irqrestore(&local->irq_init_lock, flags);
failed:
kfree(hw_priv);
prism2_release((u_long)link);