From ff487d41036035376e47972c7c522490b839ab37 Mon Sep 17 00:00:00 2001 From: Jiaxun Yang Date: Wed, 6 May 2020 13:52:45 +0800 Subject: MIPS: Truncate link address into 32bit for 32bit kernel 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 Link: https://github.com/ClangBuiltLinux/linux/issues/786 Link: https://sourceware.org/bugzilla/show_bug.cgi?id=25784 Reviewed-by: Fangrui Song Reviewed-by: Kees Cook Tested-by: Nathan Chancellor Cc: Maciej W. Rozycki Tested-by: Nick Desaulniers Signed-off-by: Thomas Bogendoerfer --- arch/mips/Makefile | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'arch/mips/Makefile') diff --git a/arch/mips/Makefile b/arch/mips/Makefile index e1c44aed8156..b6ee29e4565a 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -288,12 +288,23 @@ 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)" \ ITS_INPUTS="$(its-y)" -- cgit v1.2.3