===== arch/ppc/Kconfig 1.42 vs edited =====
--- 1.42/arch/ppc/Kconfig	Wed Jul 16 18:38:55 2003
+++ edited/arch/ppc/Kconfig	Fri Jul 18 01:06:59 2003
@@ -1464,6 +1464,14 @@
 	  If you say Y here, various routines which may sleep will become very
 	  noisy if they are called with a spinlock held.	
 
+config DEBUG_CONSISTENT_SYNC
+	bool "Check for unaligned buffers in consistent_sync"
+	depends on DEBUG_KERNEL
+	help
+	    This option enables checking for L1-cache line size alignment of
+	    buffers passed to consistent_sync when DMA direction is set 
+	    to PCI_DMA_FROMDEVICE. Disable for production systems.
+
 config KGDB
 	bool "Include kgdb kernel debugger"
 	depends on DEBUG_KERNEL
===== arch/ppc/mm/cachemap.c 1.13 vs edited =====
--- 1.13/arch/ppc/mm/cachemap.c	Tue May 20 23:19:04 2003
+++ edited/arch/ppc/mm/cachemap.c	Fri Jul 18 01:08:08 2003
@@ -146,6 +146,20 @@
 	case PCI_DMA_NONE:
 		BUG();
 	case PCI_DMA_FROMDEVICE:	/* invalidate only */
+
+#ifdef CONFIG_DEBUG_CONSISTENT_SYNC
+		if (unlikely(start & (L1_CACHE_LINE_SIZE - 1)) || 
+		    unlikely(end & (L1_CACHE_LINE_SIZE - 1)))
+		{
+			static unsigned int count = 0;
+			if (++count < 10){
+				printk(KERN_WARNING
+				    "consistent_sync: 0x%08lx-0x%08lx "
+				    "is not properly aligned\n", start, end);
+				dump_stack();    
+			}	    
+		}        
+#endif
 		invalidate_dcache_range(start, end);
 		break;
 	case PCI_DMA_TODEVICE:		/* writeback only */