ARM: 8867/1: vdso: pass --be8 to linker if necessary

[ Upstream commit c5d0e49e8d8f1a23034fdf8e935afc0c8f7ae27d ]

The commit fe00e50b2db8 ("ARM: 8858/1: vdso: use $(LD) instead of $(CC)
to link VDSO") removed the passing of CFLAGS, since ld doesn't take
those directly. However, prior, big-endian ARM was relying on gcc to
translate its -mbe8 option into ld's --be8 option. Lacking this, ld
generated be32 code, making the VDSO generate SIGILL when called by
userspace.

This commit passes --be8 if CONFIG_CPU_ENDIAN_BE8 is enabled.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>

arch/arm/vdso/Makefile

@@ -10,9 +10,10 @@ obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
 ccflags-y := -fPIC -fno-common -fno-builtin -fno-stack-protector
 ccflags-y += -DDISABLE_BRANCH_PROFILING
 
-ldflags-y = -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
+ldflags-$(CONFIG_CPU_ENDIAN_BE8) := --be8
+ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \
 	    -z max-page-size=4096 -z common-page-size=4096 \
-	    -nostdlib -shared \
+	    -nostdlib -shared $(ldflags-y) \
 	    $(call ld-option, --hash-style=sysv) \
 	    $(call ld-option, --build-id) \
 	    -T