If UNUSED_KSYMS_WHITELIST is a file generated before Kbuild runs, and the source tree is in a read-only filesystem, the developer must put the file somewhere and specify an absolute path to UNUSED_KSYMS_WHITELIST. This worked, but if IKCONFIG=y, an absolute path is embedded into .config and eventually into vmlinux, causing the build to be less reproducible when building on a different machine. This patch makes the handling of UNUSED_KSYMS_WHITELIST to be similar to MODULE_SIG_KEY. First, check if UNUSED_KSYMS_WHITELIST is an absolute path, just as before this patch. If so, use the path as is. If it is a relative path, use wildcard to check the existence of the file below objtree first. If it does not exist, fall back to the original behavior of adding $(srctree)/ before the value. After this patch, the developer can put the generated file in objtree, then use a relative path against objtree in .config, eradicating any absolute paths that may be evaluated differently on different machines. Signed-off-by: Yifan Hong <elsk@xxxxxxxxxx> --- V1 -> V2: properly handle absolute paths by treating them as-is. kernel/module/Kconfig | 2 +- scripts/Makefile.modpost | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig index f3e0329337f6..cb8377a18927 100644 --- a/kernel/module/Kconfig +++ b/kernel/module/Kconfig @@ -392,7 +392,7 @@ config UNUSED_KSYMS_WHITELIST exported at all times, even in absence of in-tree users. The value to set here is the path to a text file containing the list of symbols, one per line. The path can be absolute, or relative to the kernel - source tree. + source or obj tree. config MODULES_TREE_LOOKUP def_bool y diff --git a/scripts/Makefile.modpost b/scripts/Makefile.modpost index 739402f45509..36952638bbc6 100644 --- a/scripts/Makefile.modpost +++ b/scripts/Makefile.modpost @@ -94,7 +94,7 @@ targets += .vmlinux.objs ifdef CONFIG_TRIM_UNUSED_KSYMS ksym-wl := $(CONFIG_UNUSED_KSYMS_WHITELIST) -ksym-wl := $(if $(filter-out /%, $(ksym-wl)),$(srctree)/)$(ksym-wl) +ksym-wl := $(if $(filter-out /%, $(ksym-wl)),$(if $(wildcard $(ksym-wl)),,$(srctree)/))$(ksym-wl) modpost-args += -t $(addprefix -u , $(ksym-wl)) modpost-deps += $(ksym-wl) endif -- 2.44.0.478.gd926399ef9-goog
