Messages in this thread | | | From | Laura Abbott <> | Subject | [PATCHv3 0/2] Salted build ids via linker sections | Date | Tue, 22 May 2018 17:19:37 -0700 |
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Hi,
This is v3 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 about adding some extra information via a .comment which will affect the build id calculation but just get stripped out. ""
I mentioned in the previous version that there were problems with sporadic build failures. v3 switches to generating the linker script directly instead of a header + a linker script to avoid this problem. I also dropped the Kconfig completely (I can add it back as a guard if this seems not small enough to want all the time). I've also dropped the RFC tag since it's well formed enough at this point.
Laura Abbott (2): kbuild: Introduce build-salt linker script x86/vdso: Add build salt to the vDSO
Makefile | 4 +++- arch/x86/entry/vdso/Makefile | 4 +++- scripts/.gitignore | 1 + scripts/Makefile | 9 ++++++++- scripts/gensalt | 22 ++++++++++++++++++++++ scripts/link-vmlinux.sh | 3 ++- 6 files changed, 39 insertions(+), 4 deletions(-) create mode 100755 scripts/gensalt
-- 2.17.0
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