4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Andrey Ryabinin <aryabi...@virtuozzo.com>

commit be3606ff739d1c1be36389f8737c577ad87e1f57 upstream.

The kernel doesn't boot with both PROFILE_ANNOTATED_BRANCHES=y and KASAN=y
options selected. With branch profiling enabled we end up calling
ftrace_likely_update() before kasan_early_init(). ftrace_likely_update() is
built with KASAN instrumentation, so calling it before kasan has been
initialized leads to crash.

Use DISABLE_BRANCH_PROFILING define to make sure that we don't call
ftrace_likely_update() from early code before kasan_early_init().

Fixes: ef7f0d6a6ca8 ("x86_64: add KASan support")
Reported-by: Fengguang Wu <fengguang...@intel.com>
Signed-off-by: Andrey Ryabinin <aryabi...@virtuozzo.com>
Cc: kasan-...@googlegroups.com
Cc: Alexander Potapenko <gli...@google.com>
Cc: Andrew Morton <a...@linux-foundation.org>
Cc: l...@01.org
Cc: Dmitry Vyukov <dvyu...@google.com>
Link: http://lkml.kernel.org/r/20170313163337.1704-1-aryabi...@virtuozzo.com
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 arch/x86/kernel/head64.c    |    1 +
 arch/x86/mm/kasan_init_64.c |    1 +
 2 files changed, 2 insertions(+)

--- a/arch/x86/kernel/head64.c
+++ b/arch/x86/kernel/head64.c
@@ -4,6 +4,7 @@
  *  Copyright (C) 2000 Andrea Arcangeli <and...@suse.de> SuSE
  */
 
+#define DISABLE_BRANCH_PROFILING
 #include <linux/init.h>
 #include <linux/linkage.h>
 #include <linux/types.h>
--- a/arch/x86/mm/kasan_init_64.c
+++ b/arch/x86/mm/kasan_init_64.c
@@ -1,3 +1,4 @@
+#define DISABLE_BRANCH_PROFILING
 #define pr_fmt(fmt) "kasan: " fmt
 #include <linux/bootmem.h>
 #include <linux/kasan.h>


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