powerpc: ftrace, added missing icache flush

Impact: fix to PowerPC code modification

After modifying code it is essential to flush the icache. This patch
adds the missing flush.
Reported-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/powerpc/kernel/ftrace.c

@@ -271,6 +271,9 @@ __ftrace_make_nop(struct module *mod,
 	if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
 		return -EPERM;
 
+
+	flush_icache_range(ip, ip + 8);
+
 	return 0;
 }
 
@@ -342,6 +345,8 @@ __ftrace_make_nop(struct module *mod,
 	if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
 		return -EPERM;
 
+	flush_icache_range(ip, ip + 8);
+
 	return 0;
 }
 #endif /* PPC64 */
@@ -438,6 +443,8 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 	if (probe_kernel_write((void *)ip, op, MCOUNT_INSN_SIZE * 2))
 		return -EPERM;
 
+	flush_icache_range(ip, ip + 8);
+
 	return 0;
 }
 #else
@@ -481,6 +488,8 @@ __ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 	if (probe_kernel_write((void *)ip, &op, MCOUNT_INSN_SIZE))
 		return -EPERM;
 
+	flush_icache_range(ip, ip + 8);
+
 	return 0;
 }
 #endif /* CONFIG_PPC64 */