When building with -fstack-protector, gcc emits the __stack_chk_guard and __stack_chk_fail symbols to check for stack stability. These symbols are defined in vmlinux but the generated vmlinux.bin that is used to create the compressed vmlinuz image has no symbol table so the linker can't find these symbols during the final linking phase. As a result of which, we need either to redefine these symbols just for the compressed image or drop the -fstack-protector option when building the compressed image. This patch implements the latter of two options. Fixes the following linking problem: dbg.c:(.text+0x7c): undefined reference to `__stack_chk_guard' dbg.c:(.text+0x80): undefined reference to `__stack_chk_guard' dbg.c:(.text+0xd4): undefined reference to `__stack_chk_guard' dbg.c:(.text+0xec): undefined reference to `__stack_chk_fail' Signed-off-by: Markos Chandras <markos.chandras@xxxxxxxxxx> --- This patch is for the upstream-sfr/mips-for-linux-next tree --- arch/mips/boot/compressed/Makefile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile index bbaa1d4..bb1dbf4 100644 --- a/arch/mips/boot/compressed/Makefile +++ b/arch/mips/boot/compressed/Makefile @@ -18,6 +18,8 @@ BOOT_HEAP_SIZE := 0x400000 # Disable Function Tracer KBUILD_CFLAGS := $(shell echo $(KBUILD_CFLAGS) | sed -e "s/-pg//") +KBUILD_CFLAGS := $(filter-out -fstack-protector, $(KBUILD_CFLAGS)) + KBUILD_CFLAGS := $(LINUXINCLUDE) $(KBUILD_CFLAGS) -D__KERNEL__ \ -DBOOT_HEAP_SIZE=$(BOOT_HEAP_SIZE) -D"VMLINUX_LOAD_ADDRESS_ULL=$(VMLINUX_LOAD_ADDRESS)ull" -- 1.8.2.1
