Re: [PATCH] perf(message): avoid buffer copy during command parsing

[Jarkko Sakkinen <jarkko@kernel.org>]

On Sun, Aug 31, 2025 at 06:19:22PM +0300, Jarkko Sakkinen wrote:
> On Sun, Aug 31, 2025 at 06:01:45PM +0300, Jarkko Sakkinen wrote:
> > `tpm_parse_command` copies handles and parameters to a fixed-size temporary
> > 4 KiB buffer on the stack before invoking a command parser.
> > 
> > Introduce `TpmParseCommandBody` trait implemented by `tpm_struct!`,
> > providing accessors for handles and parameters in the original command
> > buffer, thus zeroing out the large stack allocation.
> > 
> > Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
> > ---
> > I plan to backport this also to 0.10.x branch, given signficancy.
> 
> This is something left out of initial stretch, which I've had in my mind
> for some time. I postponed this change because stability was a priority
> over performance at the time.
> 
> For the sake of symmetry I want to also rename `TpmHeaderCommand` as
> `TpmCommandBuild`, make `TpmHeader` decoupled from that trait, and
> finally change the constraint in `tpm_build_command` from `C:
> TpmHeaderCommand` to `C: TpmHeader + TpmCommandBuild`.
> 
> This patch does not include that style change, given that it is first of
> all logically distinct and further cannot be backported to the 0.10.x
> branch.

As this is just backlog and dead obvious fix, I'll also apply this to
the main branch and backport to the 0.11.x branch.

BR, Jarkko