[PATCH 3.19.y-ckt 25/47] arm64: errata: Add -mpc-relative-literal-loads to build flags

[Kamal Mostafa]

3.19.8-ckt15 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: dann frazier <dann.frazier@xxxxxxxxxxxxx>

commit 67dfa1751ce71e629aad7c438e1678ad41054677 upstream.

GCC6 (and Linaro's 2015.12 snapshot of GCC5) has a new default that uses
adrp/ldr or adrp/add to address literal pools. When CONFIG_ARM64_ERRATUM_843419
is enabled, modules built with this toolchain fail to load:

  module libahci: unsupported RELA relocation: 275

This patch fixes the problem by passing '-mpc-relative-literal-loads'
to the compiler.

Fixes: df057cc7b4fa ("arm64: errata: add module build workaround for erratum #843419")
BugLink: http://bugs.launchpad.net/bugs/1533009
Acked-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Suggested-by: Christophe Lyon <christophe.lyon@xxxxxxxxxx>
Signed-off-by: Dann Frazier <dann.frazier@xxxxxxxxxxxxx>
Signed-off-by: Will Deacon <will.deacon@xxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
 arch/arm64/Makefile | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 7cf8a29..9bc0a40 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -20,6 +20,7 @@ LIBGCC 		:= $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name)
 KBUILD_DEFCONFIG := defconfig
 
 KBUILD_CFLAGS	+= -mgeneral-regs-only
+KBUILD_CFLAGS	+= $(call cc-option, -mpc-relative-literal-loads)
 ifeq ($(CONFIG_CPU_BIG_ENDIAN), y)
 KBUILD_CPPFLAGS	+= -mbig-endian
 AS		+= -EB
-- 
1.9.1