[3.13.y.z extended stable] Patch "powerpc: Fix 64 bit builds with binutils 2.24" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    powerpc: Fix 64 bit builds with binutils 2.24

to the linux-3.13.y-queue branch of the 3.13.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11.4.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 5eb2be0dc238e7b4ade3ef0c3cb3cbfd404a8244 Mon Sep 17 00:00:00 2001
From: Guenter Roeck <linux at roeck-us.net>
Date: Thu, 15 May 2014 09:33:42 -0700
Subject: powerpc: Fix 64 bit builds with binutils 2.24

commit 7998eb3dc700aaf499f93f50b3d77da834ef9e1d upstream.

With binutils 2.24, various 64 bit builds fail with relocation errors
such as

arch/powerpc/kernel/built-in.o: In function `exc_debug_crit_book3e':
	(.text+0x165ee): relocation truncated to fit: R_PPC64_ADDR16_HI
	against symbol `interrupt_base_book3e' defined in .text section
	in arch/powerpc/kernel/built-in.o
arch/powerpc/kernel/built-in.o: In function `exc_debug_crit_book3e':
	(.text+0x16602): relocation truncated to fit: R_PPC64_ADDR16_HI
	against symbol `interrupt_end_book3e' defined in .text section
	in arch/powerpc/kernel/built-in.o

The assembler maintainer says:

 I changed the ABI, something that had to be done but unfortunately
 happens to break the booke kernel code.  When building up a 64-bit
 value with lis, ori, shl, oris, ori or similar sequences, you now
 should use @high and @higha in place of @h and @ha.  @h and @ha
 (and their associated relocs R_PPC64_ADDR16_HI and R_PPC64_ADDR16_HA)
 now report overflow if the value is out of 32-bit signed range.
 ie. @h and @ha assume you're building a 32-bit value. This is needed
 to report out-of-range -mcmodel=medium toc pointer offsets in @toc at h
 and @toc at ha expressions, and for consistency I did the same for all
 other @h and @ha relocs.

Replacing @h with @high in one strategic location fixes the relocation
errors. This has to be done conditionally since the assembler either
supports @h or @high but not both.

Signed-off-by: Guenter Roeck <linux at roeck-us.net>
Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 arch/powerpc/Makefile              | 4 +++-
 arch/powerpc/include/asm/ppc_asm.h | 7 ++++++-
 2 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index 0f4344e..8289e2b 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -149,7 +149,9 @@ endif

 CFLAGS-$(CONFIG_TUNE_CELL) += $(call cc-option,-mtune=cell)

-KBUILD_CPPFLAGS	+= -Iarch/$(ARCH)
+asinstr := $(call as-instr,lis 9$(comma)foo at high,-DHAVE_AS_ATHIGH=1)
+
+KBUILD_CPPFLAGS	+= -Iarch/$(ARCH) $(asinstr)
 KBUILD_AFLAGS	+= -Iarch/$(ARCH)
 KBUILD_CFLAGS	+= -msoft-float -pipe -Iarch/$(ARCH) $(CFLAGS-y)
 CPP		= $(CC) -E $(KBUILD_CFLAGS)
diff --git a/arch/powerpc/include/asm/ppc_asm.h b/arch/powerpc/include/asm/ppc_asm.h
index f595b98..7c04486 100644
--- a/arch/powerpc/include/asm/ppc_asm.h
+++ b/arch/powerpc/include/asm/ppc_asm.h
@@ -306,11 +306,16 @@ n:
  *      ld	rY,ADDROFF(name)(rX)
  */
 #ifdef __powerpc64__
+#ifdef HAVE_AS_ATHIGH
+#define __AS_ATHIGH high
+#else
+#define __AS_ATHIGH h
+#endif
 #define LOAD_REG_IMMEDIATE(reg,expr)		\
 	lis     reg,(expr)@highest;		\
 	ori     reg,reg,(expr)@higher;	\
 	rldicr  reg,reg,32,31;		\
-	oris    reg,reg,(expr)@h;		\
+	oris    reg,reg,(expr)@__AS_ATHIGH;	\
 	ori     reg,reg,(expr)@l;

 #define LOAD_REG_ADDR(reg,name)			\
--
1.9.1