Re: [PATCH] tpm: Disable TCG_TPM2_HMAC by default

[James Bottomley]

On Sat, 2024-05-18 at 14:34 +0300, Jarkko Sakkinen wrote:
> Causes performance drop in initialization so needs to be opt-in.
> Distributors are capable of opt-in enabling this. Could be also
> handled by kernel-command line in the future.
> 
> Reported-by: Vitor Soares <ivitro@xxxxxxxxx>
> Closes:
> https://lore.kernel.org/linux-integrity/bf67346ef623ff3c452c4f968b7d900911e250c3.camel@xxxxxxxxx/#t

Hey, there's no response on that thread verifying the primary
generation is the culprit.  Could we at least wait for a reply before
taking such drastic action based on surmise?

I'd be really surprised if it is primary generation.  If I used an RSA
primary it would be a problem (My oldest TPM takes a couple of minutes
to generate one) but the longest I've seen an EC primary take to
generate is still less than a second.

James