Hi, On Mon, 2021-10-25 at 15:09 -0400, Ben Cotton wrote: > https://fedoraproject.org/wiki/Changes/Package_information_on_ELF_objects I like this idea. It will be really useful when multiple distros adopt it. > === New system: `.note.package` === > > The new note is created and propagated similarly to > `.note.gnu.build-id`. The difference is that we inject the > information > about package ''nevra'' from the build system. > > The implementation is very simple: `%{build_ldflags}` are extended > with a command to insert a custom note as a separate section in an > ELF > object. See [ > https://github.com/systemd/package-notes/blob/main/hello.spec > hello.spec] for an example. This is done in the default macros, so > all > packages that use the prescribed link flags will be affected. > > The note is a compact json string. This allows the format to be > trivially extensible (new fields can be added at will), easy to > process (json is extremely popular and parsers are widely available). > Using a single field rather than a set of separated notes is more > space-efficient. With multiple fields the padding and alignment > requirements cause unnecessary overhead. > > The system was designed with cross-distro collaboration and is > flexible enough to identify binaries from different packaging formats > and build systems (rpms, debs, custom binaries). > > See https://systemd.io/COREDUMP_PACKAGE_METADATA/ for detailed > description of the format. It isn't immediately clear to me which of the key's will be included. The format describes 6 standard ones: type, os, osVersion, name, version, osCpe and debugInfoUrl. But the example given later only shows type, name, version and osCpe. To me the debugInfoUrl is the most interesting because combined with the already existing build-id note it allows automagic fetching of the debuginfo and sources (and the debuginfod server could tell you the type, name and version of the archive, so in theory you don't have to include those fields, but they might still be useful if you cannot access the debuginfod url). One ELF technicality I don't see described is the alignment and padding of the ELF NOTE. Normally on GNU systems ELF NOTEs are aligned on 4 bytes (for both 32/64 bit ELF files). But the recent .note.gnu.property NOTEs are aligned on 4 bytes for 32bit systems, but 8 bytes on 64bit systems (this is causing some interesting issues trying to combine those NOTEs...). What alignment/padding will this new ELF note have? Thanks, Mark _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/devel@xxxxxxxxxxxxxxxxxxxxxxx Do not reply to spam on the list, report it: https://pagure.io/fedora-infrastructure
