From: Jiaxun Yang jiaxun.yang@flygoat.com
[ Upstream commit ff487d41036035376e47972c7c522490b839ab37 ]
LLD failed to link vmlinux with 64bit load address for 32bit ELF while bfd will strip 64bit address into 32bit silently. To fix LLD build, we should truncate load address provided by platform into 32bit for 32bit kernel.
Signed-off-by: Jiaxun Yang jiaxun.yang@flygoat.com Link: https://github.com/ClangBuiltLinux/linux/issues/786 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=25784 Reviewed-by: Fangrui Song maskray@google.com Reviewed-by: Kees Cook keescook@chromium.org Tested-by: Nathan Chancellor natechancellor@gmail.com Cc: Maciej W. Rozycki macro@linux-mips.org Tested-by: Nick Desaulniers ndesaulniers@google.com Signed-off-by: Thomas Bogendoerfer tsbogend@alpha.franken.de Signed-off-by: Sasha Levin sashal@kernel.org --- arch/mips/Makefile | 13 ++++++++++++- arch/mips/boot/compressed/Makefile | 2 +- arch/mips/kernel/vmlinux.lds.S | 2 +- 3 files changed, 14 insertions(+), 3 deletions(-)
diff --git a/arch/mips/Makefile b/arch/mips/Makefile index 1a6bac7b076f..25f3bfef9b39 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -256,12 +256,23 @@ ifdef CONFIG_64BIT endif endif
+# When linking a 32-bit executable the LLVM linker cannot cope with a +# 32-bit load address that has been sign-extended to 64 bits. Simply +# remove the upper 32 bits then, as it is safe to do so with other +# linkers. +ifdef CONFIG_64BIT + load-ld = $(load-y) +else + load-ld = $(subst 0xffffffff,0x,$(load-y)) +endif + KBUILD_AFLAGS += $(cflags-y) KBUILD_CFLAGS += $(cflags-y) -KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y) +KBUILD_CPPFLAGS += -DVMLINUX_LOAD_ADDRESS=$(load-y) -DLINKER_LOAD_ADDRESS=$(load-ld) KBUILD_CPPFLAGS += -DDATAOFFSET=$(if $(dataoffset-y),$(dataoffset-y),0)
bootvars-y = VMLINUX_LOAD_ADDRESS=$(load-y) \ + LINKER_LOAD_ADDRESS=$(load-ld) \ VMLINUX_ENTRY_ADDRESS=$(entry-y) \ PLATFORM="$(platform-y)" ifdef CONFIG_32BIT diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile index 2f77e250b91d..0fa91c981658 100644 --- a/arch/mips/boot/compressed/Makefile +++ b/arch/mips/boot/compressed/Makefile @@ -87,7 +87,7 @@ ifneq ($(zload-y),) VMLINUZ_LOAD_ADDRESS := $(zload-y) else VMLINUZ_LOAD_ADDRESS = $(shell $(obj)/calc_vmlinuz_load_addr \ - $(obj)/vmlinux.bin $(VMLINUX_LOAD_ADDRESS)) + $(obj)/vmlinux.bin $(LINKER_LOAD_ADDRESS)) endif
vmlinuzobjs-y += $(obj)/piggy.o diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S index 2d965d91fee4..612b2b301280 100644 --- a/arch/mips/kernel/vmlinux.lds.S +++ b/arch/mips/kernel/vmlinux.lds.S @@ -49,7 +49,7 @@ SECTIONS /* . = 0xa800000000300000; */ . = 0xffffffff80300000; #endif - . = VMLINUX_LOAD_ADDRESS; + . = LINKER_LOAD_ADDRESS; /* read-only */ _text = .; /* Text and read-only data */ .text : {