lkml.org 
[lkml]   [2023]   [Jul]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/1] tpm: disable hwrng for fTPM on some AMD designs
On Mon, 31 Jul 2023 10:14:05 +0000
"Jarkko Sakkinen" <jarkko@kernel.org> wrote:

> On Fri Jul 28, 2023 at 8:18 PM UTC, Daniil Stas wrote:
> > On Fri, 28 Jul 2023 19:30:18 +0000
> > "Jarkko Sakkinen" <jarkko@kernel.org> wrote:
> >
> > > On Thu Jul 27, 2023 at 3:38 PM UTC, Daniil Stas wrote:
> [...]
> > >
> > > This is needs a bit more elaboration in order to be comprehended.
> > >
> > > Do you mean by "stutter" unexpected delays and when do they
> > > happen?
> > >
> > > BR, Jarkko
> >
> > Yes, unexpected delays. They just happen randomly.
> > You can google "AMD fTPM stuttering", there are a lot of examples.
> > Here is one: https://www.youtube.com/watch?v=TYnRL-x6DVI
>
> What if you make tpm_amd_is_rng_defective() to unconditonally return
> true? Does this make the problem dissappear, or not?
>
> BR, Jarkko

I already tried compiling kernel without CONFIG_HW_RANDOM_TPM enabled,
which does the same.
Yes, it removes the issue.

\
 
 \ /
  Last update: 2023-07-31 12:29    [W:0.175 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site