Patch "powerpc: Fix compiling a BE kernel with a powerpc64le toolchain" has been added to the 4.9-stable tree

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

powerpc: Fix compiling a BE kernel with a powerpc64le toolchain

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:
powerpc-fix-compiling-a-be-kernel-with-a-powerpc64le-toolchain.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 <[email protected]> know about it.

From: Nicholas Piggin <[email protected]>
Date: Sun, 27 Nov 2016 13:46:20 +1100
Subject: powerpc: Fix compiling a BE kernel with a powerpc64le toolchain

From: Nicholas Piggin <[email protected]>

[ Upstream commit 4dc831aa88132f835cefe876aa0206977c4d7710 ]

GCC can compile with either endian, but the default ABI version is set based on the default endianness of the toolchain. Alan Modra says:

you need both -mbig and -mabi=elfv1 to make a powerpc64le gcc generate powerpc64 code

The opposite is true for powerpc64 when generating -mlittle it requires -mabi=elfv2 to generate v2 ABI, which we were already doing.

This change adds ABI annotations together with endianness for all cases, LE and BE. This fixes the case of building a BE kernel with a toolchain that is LE by default.

---
 arch/powerpc/Makefile |   11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

@@ -72,8 +72,15 @@ GNUTARGET	:= powerpc
 MULTIPLEWORD	:= -mmultiple
 endif
 
-cflags-$(CONFIG_CPU_BIG_ENDIAN)		+= $(call cc-option,-mbig-endian)
+ifdef CONFIG_PPC64
+cflags-$(CONFIG_CPU_BIG_ENDIAN)		+= $(call cc-option,-mabi=elfv1)
+cflags-$(CONFIG_CPU_BIG_ENDIAN)		+= $(call cc-option,-mcall-aixdesc)
+aflags-$(CONFIG_CPU_BIG_ENDIAN)		+= $(call cc-option,-mabi=elfv1)
+aflags-$(CONFIG_CPU_LITTLE_ENDIAN)	+= -mabi=elfv2
+endif
+
 cflags-$(CONFIG_CPU_LITTLE_ENDIAN)	+= -mlittle-endian
+cflags-$(CONFIG_CPU_BIG_ENDIAN)		+= $(call cc-option,-mbig-endian)
 ifneq ($(cc-name),clang)
   cflags-$(CONFIG_CPU_LITTLE_ENDIAN)	+= -mno-strict-align
 endif

@@ -113,7 +120,9 @@ ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
 CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv2,$(call cc-option,-mcall-aixdesc))
 AFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv2)
 else
+CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv1)
 CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mcall-aixdesc)
+AFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mabi=elfv1)
 endif
 CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mcmodel=medium,$(call cc-option,-mminimal-toc))
 CFLAGS-$(CONFIG_PPC64)	+= $(call cc-option,-mno-pointers-to-nested-functions)

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/powerpc-64s-initialize-isav3-mmu-registers-before-setting-partition-table.patch queue-4.9/powerpc-fix-compiling-a-be-kernel-with-a-powerpc64le-toolchain.patch