[PATCH AUTOSEL 5.12 26/49] riscv: Use -mno-relax when using lld linker

Sasha Levin
2021-06-07T16:13:59Z

From: Khem Raj <raj.khem@gmail.com>

[ Upstream commit ec3a5cb61146c91f0f7dcec8b7e7157a4879a9ee ]

lld does not implement the RISCV relaxation optimizations like GNU ld
therefore disable it when building with lld, Also pass it to
assembler when using external GNU assembler ( LLVM_IAS != 1 ), this
ensures that relevant assembler option is also enabled along. if these
options are not used then we see following relocations in objects

0000000000000000 R_RISCV_ALIGN *ABS*+0x0000000000000002

These are then rejected by lld
ld.lld: error: capability.c:(.fixup+0x0): relocation R_RISCV_ALIGN requires unimplemented linker relaxation; recompile with -mno-relax but the .o is already compiled with -mno-relax

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/riscv/Makefile | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index 1368d943f1f3..5243bf2327c0 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -38,6 +38,15 @@ else
KBUILD_LDFLAGS += -melf32lriscv
endif

+ifeq ($(CONFIG_LD_IS_LLD),y)
+ KBUILD_CFLAGS += -mno-relax
+ KBUILD_AFLAGS += -mno-relax
+ifneq ($(LLVM_IAS),1)
+ KBUILD_CFLAGS += -Wa,-mno-relax
+ KBUILD_AFLAGS += -Wa,-mno-relax
+endif
+endif
+
# ISA string setting
riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima
riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima
--
2.30.2