Hi. 2018-07-04 8:21 GMT+09:00 Laura Abbott <labbott@xxxxxxxxxx>: > > 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. > "" I think this information is helpful to explain the background of this work, but the cover letter cannot be committed in git. Could you add this in 1/4 please? If I read only the simple log in 1/4, I would wonder why it is useful... > 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 -- Best Regards Masahiro Yamada -- 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
