powerpc: Fix i8259 interrupt driver kernel crash on ML510

This patch fixes a null pointer exception caused by removal of
'ack()' for level interrupts in the Xilinx interrupt driver.  A recent
change to the xilinx interrupt controller removed the ack hook for
level irqs.

Signed-off-by: Roderick Colenbrander <thunderbird2k@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/arch/powerpc/sysdev/xilinx_intc.c b/arch/powerpc/sysdev/xilinx_intc.c
index 3ee1fd3..40edad5 100644 (file)
--- a/arch/powerpc/sysdev/xilinx_intc.c
+++ b/arch/powerpc/sysdev/xilinx_intc.c
@@ -234,7 +234,6 @@ static void xilinx_i8259_cascade(unsigned int irq, struct irq_desc *desc)
                generic_handle_irq(cascade_irq);
 
        /* Let xilinx_intc end the interrupt */
-       desc->chip->ack(irq);
        desc->chip->unmask(irq);
 }