[PATCH] powerpc: Fix PowerMac IRQ handling bug
The port to genirq & the new powerpc interrupt model in 2.6.18 introduced a
bug in the legacy PowerMac PIC code (used on older machines) because of a
typo potentially causing hangs due to interrupt storms. This fixes it,
along with a performance issue causing us to do spurrious retriggers after
masking an interrupt.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/powerpc/platforms/powermac/pic.c b/arch/powerpc/platforms/powermac/pic.c
index 060789e..39f7ddb 100644
--- a/arch/powerpc/platforms/powermac/pic.c
+++ b/arch/powerpc/platforms/powermac/pic.c
@@ -87,8 +87,8 @@
static void pmac_mask_and_ack_irq(unsigned int virq)
{
unsigned int src = irq_map[virq].hwirq;
- unsigned long bit = 1UL << (virq & 0x1f);
- int i = virq >> 5;
+ unsigned long bit = 1UL << (src & 0x1f);
+ int i = src >> 5;
unsigned long flags;
spin_lock_irqsave(&pmac_pic_lock, flags);
@@ -175,7 +175,7 @@
spin_lock_irqsave(&pmac_pic_lock, flags);
__clear_bit(src, ppc_cached_irq_mask);
- __pmac_set_irq_mask(src, 0);
+ __pmac_set_irq_mask(src, 1);
spin_unlock_irqrestore(&pmac_pic_lock, flags);
}