Re: [patch 1/2] powerpc: rmb fix

quoted

 #define mb()   __asm__ __volatile__ ("sync" : : : "memory")
-#define rmb()  __asm__ __volatile__ (__stringify(LWSYNC) : : : 
"memory")
+#define rmb()  __asm__ __volatile__ ("sync" : : : "memory")
 #define wmb()  __asm__ __volatile__ ("sync" : : : "memory")
 #define read_barrier_depends()  do { } while(0)

@@ -42,7 +42,7 @@
 #ifdef __KERNEL__
 #ifdef CONFIG_SMP
 #define smp_mb()	mb()
-#define smp_rmb()	rmb()
+#define smp_rmb()	__asm__ __volatile__ (__stringify(LWSYNC) : : : 

"memory")
 #define smp_wmb()	eieio()
 #define smp_read_barrier_depends()	read_barrier_depends()
 #else

I had to think about this one for awhile.  It looks at first glance to 
be the right
thing to do.  But I do wonder how long rmb() has been lwsync

Since the {ppc,ppc64} -> powerpc merge.

and if as a practical matter that has caused any problems?

It has not as far as I know.

If this isn't causing any problems maybe there
is some loigic we are overlooking?

The I/O accessor functions enforce the necessary ordering
already I believe.


Segher