arm64: remove no-op -p linker flag

(commit 1a381d4a0a9a0f999a13faaba22bf6b3fc80dcb9 upstream)

Linking the ARM64 defconfig kernel with LLVM lld fails with the error:

  ld.lld: error: unknown argument: -p
  Makefile:1015: recipe for target 'vmlinux' failed

Without this flag, the ARM64 defconfig kernel successfully links with
lld and boots on Dragonboard 410c.

After digging through binutils source and changelogs, it turns out that
-p is only relevant to ancient binutils installations targeting 32-bit
ARM.  binutils accepts -p for AArch64 too, but it's always been
undocumented and silently ignored.  A comment in
ld/emultempl/aarch64elf.em explains that it's "Only here for backwards
compatibility".

Since this flag is a no-op on ARM64, we can safely drop it.

Acked-by: Will Deacon <will.deacon@arm.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Hackmann <ghackmann@google.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[sw0312.kim: cherry-pick stable linux-4.9.y commit 272991176af2 for gcc 9 build]
Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Change-Id: I47c82851c886f2b1d3af3e65ef7e7131ea877b62

diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index c2da45967059d212d0d28e69fcf03190df213b8d..62ab3539f6998094b3f66ce1a670e3515b07789e 100644 (file)
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -10,7 +10,7 @@
 #
 # Copyright (C) 1995-2001 by Russell King
 
-LDFLAGS_vmlinux        :=-p --no-undefined -X
+LDFLAGS_vmlinux        :=--no-undefined -X
 CPPFLAGS_vmlinux.lds = -DTEXT_OFFSET=$(TEXT_OFFSET)
 GZFLAGS                :=-9