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Date:   Fri, 07 Oct 2022 19:36:51 -0700
From:   Kees Cook <keescook@chromium.org>
To:     "Guilherme G. Piccoli" <gpiccoli@igalia.com>
CC:     Ard Biesheuvel <ardb@kernel.org>, linux-kernel@vger.kernel.org,
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Subject: =?US-ASCII?Q?Re=3A_=5BPATCH_8/8=5D_efi=3A_pstore=3A_Add_modul?= =?US-ASCII?Q?e_parameter_for_setting_the_record_size?=
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On October 7, 2022 4:29:55 PM PDT, "Guilherme G=2E Piccoli" <gpiccoli@igal=
ia=2Ecom> wrote:
>On 07/10/2022 16:32, Kees Cook wrote:
>> [=2E=2E=2E]
>> Given OVMF showing this as a max, it doesn't seem right to also make
>> this a minimum? Perhaps choose a different minimum to be enforced=2E
>
>Hi Kees! Through my tests, I've noticed low values tend to cause issues
>(didn't go further in the investigation), IIRC even 512 caused problems
>on "deflate" (worked in the others)=2E
>
>I'll try again 512 to see how it goes, but I'm not so sure what would be
>the use of such low values, it does truncate a lot and "pollute" the
>pstore fs with many small files=2E But I can go with any value you/Ard
>think is appropriate (given it works with all compression algorithms
>heh) - currently the minimum of 1024 is enforced in the patch=2E

Right, but not everyone uses compression=2E On the other hand, this was ne=
ver configurable before, so, sure, let's do 1k as a minimum=2E (And a comme=
nt in the source=2E)


--=20
Kees Cook