[PATCH] powerpc: fix altivec_unavailable_exception Oopses

altivec_unavailable_exception is called without setting r3... it looks like
the r3 that actually gets passed in as struct pt_regs *regs is the
undisturbed value of r3 at the time the altivec instruction was encountered.
The user actually gets to choose the pt_regs printed in the Oops!

This fixes the oops by passing the correct pt_regs pointer to
altivec_unavailable_exception.
Signed-off-by: Alan Curry <pacman@TheWorld.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/kernel/head_32.S

@@ -714,6 +714,7 @@ AltiVecUnavailable:
 #ifdef CONFIG_ALTIVEC
 	bne	load_up_altivec		/* if from user, just load it up */
 #endif /* CONFIG_ALTIVEC */
+	addi	r3,r1,STACK_FRAME_OVERHEAD
 	EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception)
 
 PerformanceMonitor:

arch/ppc/kernel/head.S

@@ -751,6 +751,7 @@ AltiVecUnavailable:
 #ifdef CONFIG_ALTIVEC
 	bne	load_up_altivec		/* if from user, just load it up */
 #endif /* CONFIG_ALTIVEC */
+	addi	r3,r1,STACK_FRAME_OVERHEAD
 	EXC_XFER_EE_LITE(0xf20, altivec_unavailable_exception)
 
 #ifdef CONFIG_PPC64BRIDGE