--- linux-2.6.16.1/drivers/ide/ide-io.c	2006-03-28 07:49:02.000000000 +0100
+++ linux-2.6.16.1-imac-sky2-rtc/drivers/ide/ide-io.c	2006-05-15 03:24:57.000000000 +0100
@@ -1525,6 +1525,8 @@
 			 * Whack the status register, just in case
 			 * we have a leftover pending IRQ.
 			 */
+			/* Ack the interrupt for ich7 - XXX possible race */
+			hwif->OUTB( (hwif->INB(hwif->dma_status) |4) & ~2, hwif->dma_status);
 			(void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]);
 #endif /* CONFIG_BLK_DEV_IDEPCI */
 		}
@@ -1567,6 +1569,9 @@
 	startstop = handler(drive);
 	spin_lock_irq(&ide_lock);
 
+	/* Ack the interrupt for ich7 - XXX possible race */
+	hwif->OUTB( (hwif->INB(hwif->dma_status) |4) & ~2, hwif->dma_status);
+
 	/*
 	 * Note that handler() may have set things up for another
 	 * interrupt to occur soon, but it cannot happen until