Add "Map" kbuild option, so that "make Map=1" would save vmlinux linker map into vmlinux.map, which is quite useful during making kernel changes related to how the kernel is composed.
KBUILD_SAVE_LINK_MAP flag is exported and architectures supporting compressed kernel images might respect it and produce arch/*/boot/compressed/vmlinux.map for the decompressor code as well. Signed-off-by: Vasily Gorbik <[email protected]> --- .gitignore | 1 + Makefile | 14 ++++++++++++++ 2 files changed, 15 insertions(+) diff --git a/.gitignore b/.gitignore index 97ba6b79834c..1d2308e597ad 100644 --- a/.gitignore +++ b/.gitignore @@ -44,6 +44,7 @@ *.xz Module.symvers modules.builtin +vmlinux.map # # Top-level generic files diff --git a/Makefile b/Makefile index 7a3c4548162b..f1790deae03b 100644 --- a/Makefile +++ b/Makefile @@ -176,6 +176,14 @@ ifndef KBUILD_CHECKSRC KBUILD_CHECKSRC = 0 endif +# Use 'make Map=1' to enable saving linker map file(s): +# vmlinux.map for vmlinux, +# (arch/*/boot/compressed/vmlinux.map for arch/*/boot/compressed/vmlinux) + +ifeq ("$(origin Map)", "command line") + export KBUILD_SAVE_LINK_MAP := $(Map) +endif + # Use make M=dir to specify directory of external module to build # Old syntax make ... SUBDIRS=$PWD is still supported # Setting the environment variable KBUILD_EXTMOD take precedence @@ -838,6 +846,11 @@ ifeq ($(CONFIG_STRIP_ASM_SYMS),y) LDFLAGS_vmlinux += $(call ld-option, -X,) endif +ifdef KBUILD_SAVE_LINK_MAP +LDFLAGS_vmlinux += -Map=vmlinux.map +CLEAN_FILES += vmlinux.map +endif + # insure the checker run with the right endianness CHECKFLAGS += $(if $(CONFIG_CPU_BIG_ENDIAN),-mbig-endian,-mlittle-endian) @@ -1434,6 +1447,7 @@ help: @echo ' 2: warnings which occur quite often but may still be relevant' @echo ' 3: more obscure warnings, can most likely be ignored' @echo ' Multiple levels can be combined with W=12 or W=123' + @echo ' make Map=1 [targets] Save vmlinux linker map file(s)' @echo '' @echo 'Execute "make" or "make all" to build all targets marked with [*] ' @echo 'For further info see the ./README file' -- 2.18.0.13.gd42ae10
