Author: nbd Date: 2015-10-30 16:20:12 +0100 (Fri, 30 Oct 2015) New Revision: 47290
Modified: trunk/include/kernel-defaults.mk trunk/rules.mk trunk/scripts/strip-kmod.sh Log: build: Allow kernel modules to set build ID debug symbol This change adds support for specifying a build ID for kernel modules. This is done by setting PKG_BUILD_ID to a hexadecimal string, which will then be passed to the kernel linker. In addition, when this flag is set, the build ID debug symbol (.note.gnu.build-id) will not be stripped from the kernel module. This symbol is exported in sysfs by the kernel (if the kernel is compiled with CONFIG_KALLSYMS) and so can be used to uniquely identify a version of a kernel module in a running kernel. This is useful for keeping track of different versions of a module when doing experiments and development. Modules that specify the build ID will be ~100 bytes larger (depending on the length of the build ID specified). There is no size difference for kernel modules that do not set this variable. Signed-off-by: Toke H?\195?\184iland-J?\195?\184rgensen <[email protected]> Modified: trunk/include/kernel-defaults.mk =================================================================== --- trunk/include/kernel-defaults.mk 2015-10-30 15:18:22 UTC (rev 47289) +++ trunk/include/kernel-defaults.mk 2015-10-30 15:20:12 UTC (rev 47290) @@ -11,7 +11,8 @@ ARCH="$(LINUX_KARCH)" \ KBUILD_HAVE_NLS=no \ CONFIG_SHELL="$(BASH)" \ - $(if $(findstring c,$(OPENWRT_VERBOSE)),V=1,V='') + $(if $(findstring c,$(OPENWRT_VERBOSE)),V=1,V='') \ + $(if $(PKG_BUILD_ID),LDFLAGS_MODULE=--build-id=0x$(PKG_BUILD_ID)) ifdef CONFIG_STRIP_KERNEL_EXPORTS KERNEL_MAKEOPTS += \ Modified: trunk/rules.mk =================================================================== --- trunk/rules.mk 2015-10-30 15:18:22 UTC (rev 47289) +++ trunk/rules.mk 2015-10-30 15:20:12 UTC (rev 47290) @@ -273,8 +273,9 @@ STRIP:=$(STAGING_DIR_HOST)/bin/sstrip endif endif - RSTRIP:= \ + RSTRIP= \ export CROSS="$(TARGET_CROSS)" \ + $(if $(PKG_BUILD_ID),KEEP_BUILD_ID=1) \ $(if $(CONFIG_KERNEL_KALLSYMS),NO_RENAME=1) \ $(if $(CONFIG_KERNEL_PROFILING),KEEP_SYMBOLS=1); \ NM="$(TARGET_CROSS)nm" \ Modified: trunk/scripts/strip-kmod.sh =================================================================== --- trunk/scripts/strip-kmod.sh 2015-10-30 15:18:22 UTC (rev 47289) +++ trunk/scripts/strip-kmod.sh 2015-10-30 15:20:12 UTC (rev 47290) @@ -18,11 +18,14 @@ ARGS="-x -G __this_module --strip-unneeded" fi +if [ -z "$KEEP_BUILD_ID" ]; then + ARGS="$ARGS -R .note.gnu.build-id" +fi + ${CROSS}objcopy \ -R .comment \ -R .pdr \ -R .mdebug.abi32 \ - -R .note.gnu.build-id \ -R .gnu.attributes \ -R .reginfo \ $ARGS \ _______________________________________________ openwrt-commits mailing list [email protected] https://lists.openwrt.org/cgi-bin/mailman/listinfo/openwrt-commits
