To summarize, when building corboot, .config is copied into the final CBFS archive in coreboot.rom. The current location "/config" is overwritten by whichever prefix built last: fallback or normal. The change puts the prefix in front of .config and "revision" in order to keep them from being clobbered.
BEFORE:
FMAP REGION: COREBOOT Name Offset Type Size Comp cbfs master header 0x0 cbfs header 32 none fallback/romstage 0x80 stage 37916 none fallback/ramstage 0x9500 stage 64699 none fallback/dsdt.aml 0x28b00 raw 12135 none fallback/payload 0x19200 simple elf 60319 none config 0x27e00 raw 403 none revision 0x28000 raw 577 none normal/romstage 0xcff80 stage 50044 none
.... issue: does config and revision belong to fallback or normal?
AFTER:
FMAP REGION: COREBOOT Name Offset Type Size Comp cbfs master header 0x0 cbfs header 32 none fallback/romstage 0x80 stage 37916 none fallback/ramstage 0x9500 stage 64699 none fallback/payload 0x19200 simple elf 60319 none fallback/config 0x27e00 raw 403 none fallback/revision 0x28000 raw 577 none normal/romstage 0xcff80 stage 50044 none normal/ramstage 0xf1400 stage 96840 none normal/postcar 0x108e80 stage 19532 none normal/config 0xcc180 raw 575 none normal/revision 0xcc400 raw 680 none normal/dsdt.aml 0xcc700 raw 12600 none normal/payload 0x12b5c0 simple elf 451681 none .... solution: add prefix!
So, there is some discussion started:
https://review.coreboot.org/c/coreboot/+/42028
So far, after 3 people reviewing, there have been 2 identified users of the .config and "revision" files embedded in CFBS, which may be affected by adding the prefix fallback/normal/<custom>
It was suggested to reach out via the mailing list, to see if anyone else would be affected by this change.
Regards,
Jeremy