From: Markos Chandras Date: Mon, 1 Jul 2013 09:38:30 +0000 (+0000) Subject: MIPS: Boot: Compressed: Remove -fstack-protector from CFLAGS X-Git-Tag: drm-fsl-dcu-for-next~7145^2~45 X-Git-Url: http://git.agner.ch/gitweb/?p=linux-drm-fsl-dcu.git;a=commitdiff_plain;h=23df34155b29674465813b327647cd79722aa659 MIPS: Boot: Compressed: Remove -fstack-protector from CFLAGS 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' [ralf@linux-mips.org: I'm applying this before the patch that actually adds stack protector support for MIPS. This means, it will not be possible to trigger above error message with any commit from the tree but rather they are what one would hit without this commit.] Signed-off-by: Markos Chandras Cc: linux-mips@linux-mips.org Cc: Markos Chandras Patchwork: https://patchwork.linux-mips.org/patch/5575/ Signed-off-by: Ralf Baechle --- diff --git a/arch/mips/boot/compressed/Makefile b/arch/mips/boot/compressed/Makefile index bbaa1d4beb6d..bb1dbf4abb9d 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"