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 5977884b008e..a4a06d173858 100644 --- a/arch/mips/Makefile +++ b/arch/mips/Makefile @@ -279,12 +279,23 @@ 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="$(its-y)" diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile index baa34e4deb78..516e593a8ee9 100644 --- a/arch/mips/boot/compressed/Makefile +++ b/arch/mips/boot/compressed/Makefile @@ -87,7 +87,7 @@ ifneq ($(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 UIMAGE_LOADADDR = $(VMLINUZ_LOAD_ADDRESS)
diff --git a/arch/mips/kernel/vmlinux.lds.S b/arch/mips/kernel/vmlinux.lds.S index 36f2e860ba3e..be63fff95b2a 100644 --- a/arch/mips/kernel/vmlinux.lds.S +++ b/arch/mips/kernel/vmlinux.lds.S @@ -50,7 +50,7 @@ SECTIONS /* . = 0xa800000000300000; */ . = 0xffffffff80300000; #endif - . = VMLINUX_LOAD_ADDRESS; + . = LINKER_LOAD_ADDRESS; /* read-only */ _text = .; /* Text and read-only data */ .text : {