This is a note to let you know that I've just added the patch titled
x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-kasan-fix-boot-with-kasan-y-and-profile_annotated_branches-y.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From be3606ff739d1c1be36389f8737c577ad87e1f57 Mon Sep 17 00:00:00 2001
From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Date: Mon, 13 Mar 2017 19:33:37 +0300
Subject: x86/kasan: Fix boot with KASAN=y and PROFILE_ANNOTATED_BRANCHES=y
From: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
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.wu@xxxxxxxxx>
Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: kasan-dev@xxxxxxxxxxxxxxxx
Cc: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: lkp@xxxxxx
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/20170313163337.1704-1-aryabinin@xxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
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 <andrea@xxxxxxx> 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>
Patches currently in stable-queue which might be from aryabinin@xxxxxxxxxxxxx are
queue-4.9/x86-kasan-fix-boot-with-kasan-y-and-profile_annotated_branches-y.patch