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Date:   Tue, 18 Oct 2022 11:10:53 -0300
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Subject: Re: [PATCH 0/5] pstore: Use zstd directly by default for compression
To:     Ard Biesheuvel <ardb@kernel.org>, Kees Cook <keescook@chromium.org>
Cc:     Tony Luck <tony.luck@intel.com>, Nick Terrell <terrelln@fb.com>,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
References: <20221018020519.never.337-kees@kernel.org>
 <CAMj1kXGjF63wK7m8BqC=WX6sA425BTVwQWk9ERN3gG8s==4mjw@mail.gmail.com>
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From:   "Guilherme G. Piccoli" <gpiccoli@igalia.com>
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On 18/10/2022 05:20, Ard Biesheuvel wrote:
> [...]
> So again, I suggest to simply drop this non-feature, and standardize
> on either zlib or zstd using the library interface exclusively. If
> someone present a compelling use case, we can always consider adding
> it back in some form.
> 
> As for the choice of algorithm, given the equal performance using the
> default compression level, and the difference in code size, I don't
> see why zstd should be preferred here. If anything, it only increases
> the likelihood of hitting another error if we are panicking due to
> some memory corruption issue.

I think it's a good argument - would zlib be simpler in code than zstd?
I've checked the zstd patch from Kees - not complex per se, but would be
great if we could have a simple mechanism, without the need of the ifdef
there for example...

Cheers,


Guilherme