2.6.37-stable review patch.  If anyone has any objections, please let us know.

------------------

From: Stanislaw Gruszka <[email protected]>

commit 4e5518ca53be29c1ec3c00089c97bef36bfed515 upstream.

pcmcia_request_irq() and pcmcia_enable_device() are intended
to be called from process context (first function allocate memory
with GFP_KERNEL, second take a mutex). We can not take spin lock
and call them.

It's safe to move spin lock after pcmcia_enable_device() as we
still hold off IRQ until dev->base_addr is 0 and driver will
not proceed with interrupts when is not ready.

Patch resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=643758

Reported-and-tested-by: [email protected]
Signed-off-by: Stanislaw Gruszka <[email protected]>
Signed-off-by: John W. Linville <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/net/wireless/hostap/hostap_cs.c |   15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

--- a/drivers/net/wireless/hostap/hostap_cs.c
+++ b/drivers/net/wireless/hostap/hostap_cs.c
@@ -518,22 +518,21 @@ static int prism2_config(struct pcmcia_d
        hw_priv->link = link;
 
        /*
-        * Make sure the IRQ handler cannot proceed until at least
-        * dev->base_addr is initialized.
+        * We enable IRQ here, but IRQ handler will not proceed
+        * until dev->base_addr is set below. This protect us from
+        * receive interrupts when driver is not initialized.
         */
-       spin_lock_irqsave(&local->irq_init_lock, flags);
-
        ret = pcmcia_request_irq(link, prism2_interrupt);
        if (ret)
-               goto failed_unlock;
+               goto failed;
 
        ret = pcmcia_enable_device(link);
        if (ret)
-               goto failed_unlock;
+               goto failed;
 
+       spin_lock_irqsave(&local->irq_init_lock, flags);
        dev->irq = link->irq;
        dev->base_addr = link->resource[0]->start;
-
        spin_unlock_irqrestore(&local->irq_init_lock, flags);
 
        local->shutdown = 0;
@@ -546,8 +545,6 @@ static int prism2_config(struct pcmcia_d
 
        return ret;
 
- failed_unlock:
-       spin_unlock_irqrestore(&local->irq_init_lock, flags);
  failed:
        kfree(hw_priv);
        prism2_release((u_long)link);


_______________________________________________
stable mailing list
[email protected]
http://linux.kernel.org/mailman/listinfo/stable

Reply via email to