Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (162 commits)
  tracing/kprobes: unregister_trace_probe needs to be called under mutex
  perf: expose event__process function
  perf events: Fix mmap offset determination
  perf, powerpc: fsl_emb: Restore setting perf_sample_data.period
  perf, powerpc: Convert the FSL driver to use local64_t
  perf tools: Don't keep unreferenced maps when unmaps are detected
  perf session: Invalidate last_match when removing threads from rb_tree
  perf session: Free the ref_reloc_sym memory at the right place
  x86,mmiotrace: Add support for tracing STOS instruction
  perf, sched migration: Librarize task states and event headers helpers
  perf, sched migration: Librarize the GUI class
  perf, sched migration: Make the GUI class client agnostic
  perf, sched migration: Make it vertically scrollable
  perf, sched migration: Parameterize cpu height and spacing
  perf, sched migration: Fix key bindings
  perf, sched migration: Ignore unhandled task states
  perf, sched migration: Handle ignored migrate out events
  perf: New migration tool overview
  tracing: Drop cpparg() macro
  perf: Use tracepoint_synchronize_unregister() to flush any pending tracepoint call
  ...

Fix up trivial conflicts in Makefile and drivers/cpufreq/cpufreq.c

1 files changed, 17 insertions, 16 deletions

diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 675879b65ce..1bfb6cf4dd5 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -126,16 +126,22 @@ static void __kprobes synthesize_reljump(void *from, void *to)
 }
 
 /*
- * Check for the REX prefix which can only exist on X86_64
- * X86_32 always returns 0
+ * Skip the prefixes of the instruction.
  */
-static int __kprobes is_REX_prefix(kprobe_opcode_t *insn)
+static kprobe_opcode_t *__kprobes skip_prefixes(kprobe_opcode_t *insn)
 {
+	insn_attr_t attr;
+
+	attr = inat_get_opcode_attribute((insn_byte_t)*insn);
+	while (inat_is_legacy_prefix(attr)) {
+		insn++;
+		attr = inat_get_opcode_attribute((insn_byte_t)*insn);
+	}
 #ifdef CONFIG_X86_64
-	if ((*insn & 0xf0) == 0x40)
-		return 1;
+	if (inat_is_rex_prefix(attr))
+		insn++;
 #endif
-	return 0;
+	return insn;
 }
 
 /*
@@ -272,6 +278,9 @@ static int __kprobes can_probe(unsigned long paddr)
  */
 static int __kprobes is_IF_modifier(kprobe_opcode_t *insn)
 {
+	/* Skip prefixes */
+	insn = skip_prefixes(insn);
+
 	switch (*insn) {
 	case 0xfa:		/* cli */
 	case 0xfb:		/* sti */
@@ -280,13 +289,6 @@ static int __kprobes is_IF_modifier(kprobe_opcode_t *insn)
 		return 1;
 	}
 
-	/*
-	 * on X86_64, 0x40-0x4f are REX prefixes so we need to look
-	 * at the next byte instead.. but of course not recurse infinitely
-	 */
-	if (is_REX_prefix(insn))
-		return is_IF_modifier(++insn);
-
 	return 0;
 }
 
@@ -803,9 +805,8 @@ static void __kprobes resume_execution(struct kprobe *p,
 	unsigned long orig_ip = (unsigned long)p->addr;
 	kprobe_opcode_t *insn = p->ainsn.insn;
 
-	/*skip the REX prefix*/
-	if (is_REX_prefix(insn))
-		insn++;
+	/* Skip prefixes */
+	insn = skip_prefixes(insn);
 
 	regs->flags &= ~X86_EFLAGS_TF;
 	switch (*insn) {