Patch "arm64: opcodes.h: Add arm big-endian config options before including arm header" has been added to the 4.4-stable tree

Patch "arm64: opcodes.h: Add arm big-endian config options before including arm header" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    arm64: opcodes.h: Add arm big-endian config options before including arm header

to the 4.4-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:
     arm64-opcodes.h-add-arm-big-endian-config-options-before-including-arm-header.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From a6002ec5a8c68e69706b2efd6db6d682d0ab672c Mon Sep 17 00:00:00 2001
From: James Morse <james.morse@arm.com>
Date: Thu, 24 Mar 2016 16:54:34 +0000
Subject: arm64: opcodes.h: Add arm big-endian config options before including arm header

From: James Morse <james.morse@arm.com>

commit a6002ec5a8c68e69706b2efd6db6d682d0ab672c upstream.

arm and arm64 use different config options to specify big endian. This
needs taking into account when including code/headers between the two
architectures.

A case in point is PAN, which uses the __instr_arm() macro to output
instructions. The macro comes from opcodes.h, which lives under arch/arm.
On a big-endian build the mismatched config options mean the instruction
isn't byte swapped correctly, resulting in undefined instruction exceptions
during boot:

| alternatives: patching kernel code
| kdevtmpfs[87]: undefined instruction: pc=ffffffc0004505b4
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| kdevtmpfs[87]: undefined instruction: pc=ffffffc00076231c
| Internal error: Oops - undefined instruction: 0 [#1] SMP
| Modules linked in:
| CPU: 0 PID: 87 Comm: kdevtmpfs Not tainted 4.1.16+ #5
| Hardware name: Hisilicon PhosphorHi1382 EVB (DT)
| task: ffffffc336591700 ti: ffffffc3365a4000 task.ti: ffffffc3365a4000
| PC is at dump_instr+0x68/0x100
| LR is at do_undefinstr+0x1d4/0x2a4
| pc : [<ffffffc00076231c>] lr : [<ffffffc0000811d4>] pstate: 604001c5
| sp : ffffffc3365a6450

Reported-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Xuefeng Wang <wxf.wang@hisilicon.com>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/arm64/include/asm/opcodes.h |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/arm64/include/asm/opcodes.h
+++ b/arch/arm64/include/asm/opcodes.h
@@ -1 +1,5 @@
+#ifdef CONFIG_CPU_BIG_ENDIAN
+#define CONFIG_CPU_ENDIAN_BE8 CONFIG_CPU_BIG_ENDIAN
+#endif
+
 #include <../../arm/include/asm/opcodes.h>


Patches currently in stable-queue which might be from james.morse@arm.com are

queue-4.4/arm64-opcodes.h-add-arm-big-endian-config-options-before-including-arm-header.patch