Hi, This is v5 of the series to allow unique build ids in the kernel. As a reminder of the context: "" In Fedora, the debug information is packaged separately (foo-debuginfo) and can be installed separately. There's been a long standing issue where only one version of a debuginfo info package can be installed at a time. Mark Wielaard made an effort for Fedora 27 to allow parallel installation of debuginfo (see https://fedoraproject.org/wiki/Changes/ParallelInstallableDebuginfo for more details) Part of the requirement to allow this to work is that build ids are unique between builds. The existing upstream rpm implementation ensures this by re-calculating the build-id using the version and release as a seed. This doesn't work 100% for the kernel because of the vDSO which is its own binary and doesn't get updated. After poking holes in a few of my ideas, there was a discussion with some people from the binutils team about adding --build-id-salt to let ld do the calculation debugedit is doing. There was a counter proposal made to add in the salt while building. The easiest proposal was to add an item in the linker script vs. linking in an object since we need the salt to go in every module as well as the kernel and vmlinux. "" v5 uses the approach suggested by Masahiro Yamada which uses the existing ELF note macro to more easily add the salt (vs previous approaches which tried to adjust via linker section). If arch maintainers are okay, I'd like acks for this so this can go through the kbuild tree. Thanks, Laura Laura Abbott (4): kbuild: Add build salt to the kernel and modules x86: Add build salt to the vDSO powerpc: Add build salt to the vDSO arm64: Add build salt to the vDSO arch/arm64/kernel/vdso/note.S | 3 +++ arch/powerpc/kernel/vdso32/note.S | 3 +++ arch/x86/entry/vdso/vdso-note.S | 3 +++ arch/x86/entry/vdso/vdso32/note.S | 3 +++ include/linux/build-salt.h | 20 ++++++++++++++++++++ init/Kconfig | 9 +++++++++ init/version.c | 3 +++ scripts/mod/modpost.c | 3 +++ 8 files changed, 47 insertions(+) create mode 100644 include/linux/build-salt.h -- 2.17.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
