Re: [PATCH] tpm: tis: Increase the default for timeouts B and C

[Jonathan McDowell]

On Thu, Apr 03, 2025 at 09:45:21PM +0300, Jarkko Sakkinen wrote:
> On Wed, Apr 02, 2025 at 06:45:40PM +0100, Jonathan McDowell wrote:
> > On Wed, Apr 02, 2025 at 07:21:30PM +0200, Michal Suchanek wrote:
> > > With some Infineon chips the timeouts in tpm_tis_send_data (both B and
> > > C) can reach up to about 2250 ms.
> > >
> > > Extend the timeout duration to accommodate this.
> >
> > The problem here is the bump of timeout_c is going to interact poorly with
> > the Infineon errata workaround, as now we'll wait 4s instead of 200ms to
> > detect the stuck status change.
> >
> > (Also shouldn't timeout_c already end up as 750ms, as it's
> > max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C), and TIS_SHORT_TIMEOUT is 750 vs 200
> > for TPM2_TIMEOUT_C? That doesn't seem to be borne out by your logs, nor my
> > results.)
>
> Just noticed that the commit did not end up having fixes etc. tags:
>
> https://web.git.kernel.org/pub/scm/linux/kernel/git/jarkko/linux-tpmdd.git/commit/?id=de9e33df7762abbfc2a1568291f2c3a3154c6a9d
>
> Should we forward to stable?

It's a TPM bug rather than a kernel issue, so I don't think there's a 
valid Fixes: for it, but it's certainly stable material in my mind.

J.

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