elf_reader: emit UnspecifiedPrograms into CollectionSpec
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ti-mo
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UnspecifiedPrograms into CollectionSpec
| @@ -286,7 +286,11 @@ func NewCollectionWithOptions(spec *CollectionSpec, opts CollectionOptions) (*Co | |||
| } | |||
| } | |||
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| for progName := range spec.Programs { | |||
| for progName, prog := range spec.Programs { | |||
| if prog.Type == UnspecifiedProgram { | |||
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I feel like this would be the expected behaviour, and should keep things backwards-compatible. Instead of filtering UnspecifiedPrograms out of the CollectionSpec, filter them out on their way into the kernel.
Any other ideas to accomplish this?
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Hmm. What happens if a prog array points at an UnspecifiedProgram?
Seems OK on the surface.
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Probably worth documenting this.
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The lazy-loader doesn't take this code path afaik, but the kernel should complain about an invalid program. Good point, will investigate.
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FWIW I think returning an error when a programarray references unspecifiedprogram is OK.
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I've added an explicit UnspecifiedProgram check to (collectionLoader).loadProgram() since there's not much point in trying to let the kernel load these progs. An explicit check also prevents possible dependent maps etc. from getting lazy-loaded, so some work is saved overall.
I've tested putting btf_map_init.c's tail_main() into .text, and it turns out this check isn't tripped currently, since loadProgram() operates on cs.Programs, which .text is not allowed to emit programs into. Maybe in a future patch it will, or into a cs.Functions field, etc. but in the meantime I think it doesn't hurt to have the check there.
| @@ -286,7 +286,11 @@ func NewCollectionWithOptions(spec *CollectionSpec, opts CollectionOptions) (*Co | |||
| } | |||
| } | |||
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| for progName := range spec.Programs { | |||
| for progName, prog := range spec.Programs { | |||
| if prog.Type == UnspecifiedProgram { | |||
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Hmm. What happens if a prog array points at an UnspecifiedProgram?
Seems OK on the surface.
eBPF programs emitted to sections with unknown prefixes were previously withheld from CollectionSpec.Programs. Add a ProgramSpec.SectionName field to allow the caller to determine (Attach)Type manually, and include all programs that were explicitly assigned to an ELF section. Signed-off-by: Timo Beckers <timo@isovalent.com>
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eBPF programs emitted to sections with unknown prefixes were previously withheld from CollectionSpec.Programs. Add a ProgramSpec.SectionName field to allow the caller to determine (Attach)Type manually, and include all programs that were explicitly assigned to an ELF section.