[PATCH] powerpc: Fix PowerMac IRQ handling bug
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>
Fri, 1 Sep 2006 04:27:50 +0000 (21:27 -0700)
committerLinus Torvalds <torvalds@g5.osdl.org>
Fri, 1 Sep 2006 18:39:09 +0000 (11:39 -0700)
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>
arch/powerpc/platforms/powermac/pic.c

index 060789e31c6770fa9e74d1aaebbcfe8ca3f74742..39f7ddb554eaf084f079067f9180eeb69f4fe98c 100644 (file)
@@ -87,8 +87,8 @@ static void __pmac_retrigger(unsigned int irq_nr)
 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 @@ static void pmac_mask_irq(unsigned int virq)
 
        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);
 }