ISA: Internet AD comments for draft-ietf-bpf-isa-02

[dthaler]

Internet AD comments for draft-ietf-bpf-isa-02 CC @ekline

• comment syntax:
  • https://github.com/mnot/ietf-comments/blob/main/format.md

Mostly just cosmetic things and a few clarifications questions from a novice. Nothing to hold up IETF LC, though.

Comments

S2.4

• Do you want to use RFC 2119/8174 language anywhere in here? For instance:

  "implementation must support the base32 conformance group and may support"

  -->

  "implementation MUST support the base32 conformance group and MAY support"

S3.1, others

• Consider explicitly including the bit-width of fields in the descriptive text (rather than requiring folks to count "+-+"s). E.g.

  opcode (8 bits) operation to perform, ... specific (5 bits) The format of ...

• src_reg and dst_reg appearing to be 4-bit fields but listed as having a valid decimal range of only 0-10 invites questions about R11-R15, I think.

• "Unused fields shall be cleared to zero" -> "Unused fields SHALL be cleared to zero" (iff. you decide to use 2119/8174)

  This may have already been discussed and rejected; I just cannot recall.

S4.1

• Should Table 5 show that 0xe and 0xf are presently unassigned (and possibly therefore reserved)?

S4.2

• To be clear, one of "ALU TO_LE" and "ALU TO_BE" is likely to be a no-op (depending upon the byte order of the host CPU architecture)?

S4.3

• Should Table 7 show that 0xe and 0xf are presently unassigned (and possibly therefore reserved)?

S4.3.1

• Consider indicating that this is an area for future work / out of scope of this document (since BTF is presently intended to be a separate document).

S5

• Should Table 8 show that 0x7 is presently unassigned (and possibly therefore reserved)?

Nits

S7.1.1

• "included from this group" -> "included by this group"?

[dthaler]

Proposed patch posted at https://mailarchive.ietf.org/arch/msg/bpf/OKVjbo8-GtvAncW7017dthBFYSs/

[dthaler]

S7.1.1 nit fixed in 82767c499db51d8198e7d27cfb812499ff73b610

[dthaler]

Fixed in draft-03