RE: [PATCH v2] tpm: add longer timeouts for creation commands.

From: Winkler, Tomas
Date: Tue Feb 06 2018 - 15:52:14 EST


>
> On Sun, Jan 28, 2018 at 10:17:39AM +0200, Tomas Winkler wrote:
> > TPM2_CC_Create(0x153) and TPM2_CC_CreatePrimary (0x131) involve
> > generation of crypto keys which can be a computationally intensive task.
> > The timeout is set to 3min.
> >
> > Signed-off-by: Tomas Winkler <tomas.winkler@xxxxxxxxx>
>
> This is still NAK because we need some kind of reference for the new value.
> Is that also right value for ARM64/TrustZone based TPMs?

The SPEC itself, doesn't define the timeout, except for specific commands,
also the current 'undefined' number is born in air, I wonder if you can provide the reference as well.
If I would suggest to shorten the number that would maybe a problem for other implementation,
but I don't see how the increase in timeout is adverse another implementations.
Key generation is computational intensive task because of generation of a prime number, so this is really
dependent on device capabilities, so there is no better source of definition that HW itself.

Thanks
Tomas