Re: [tpmdd-devel] [PATCH] tpm: remove chip_num parameter from in-kernel API

[PrasannaKumar Muralidharan]

On 24 October 2017 at 23:07, Jason Gunthorpe
<jgunthorpe@xxxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, Oct 24, 2017 at 10:02:00AM -0700, Dmitry Torokhov wrote:
>> tpm-rng is abomination that should be kicked out as soon as possible.
>> It wrecks havoc with the power management (TPM chip drivers may go
>> into suspend state, but tpm_rng does not do any power management and
>> happily forwards requests to suspended hardware) and may be available
>> when there is no TPM at all yet (the drivers have not been probed yet,
>> or have gotten a deferral, etc).
>
> Makes sense
>
>> TPM core should register HWRNGs when chips are ready.
>
> The main thing I've wanted from the TPM RNG is
> 'add_early_randomness'..
>
> We can certainly provide a TPM interface to hwrng, it seems
> reasonable.
>
> Excep that we already have a user api in /dev/tpm to access the
> tpm RNG, is the duplication a problem?

I tried to do that via the rfc we discussed previously. It may not be
the right way but I wanted to start the discussion via the rfc.

Thanks,
PrasannaKumar