Re: [PATCH] pstore: migrate to crypto acomp interface (take 2)

Kees Cook
2022-10-17T20:20:13Z

On Mon, Oct 17, 2022 at 09:45:08PM +0200, Ard Biesheuvel wrote:
> On Mon, 17 Oct 2022 at 21:40, Kees Cook <keescook@chromium.org> wrote:
> > Okay, so strictly speaking, eliminating the per-CPU allocation is an
> > improvement. Keeping scomp and doing in-place compression will let
> > pstore use "any" compressions method.
>
> I'm not following the point you are making here.

Sorry, I mean to say that if I leave scomp in pstore, nothing is "worse"
(i.e. the per-cpu allocation is present in both scomp and acomp). i.e.
no regression either way, but if we switch to a distinct library call,
it's an improvement on the memory utilization front.

> > Is there a crypto API that does _not_ preallocate the per-CPU stuff?
> > Because, as you say, it's a huge amount of memory on the bigger
> > systems...
>
> The library interface for each of the respective algorithms.

Where is the crypto API for just using the library interfaces, so I
don't have to be tied to a specific algo?

--
Kees Cook