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Message-ID: <41466b65a30a351d57869042e9f130cdb68aab5b.camel@HansenPartnership.com>
Subject: Re: [PATCH] tpm: Disable TCG_TPM2_HMAC by default
From: James Bottomley <James.Bottomley@HansenPartnership.com>
To: Jarkko Sakkinen <jarkko@kernel.org>, linux-integrity@vger.kernel.org
Cc: keyrings@vger.kernel.org, Vitor Soares <ivitro@gmail.com>, Peter Huewe
	 <peterhuewe@gmx.de>, Jason Gunthorpe <jgg@ziepe.ca>, open list
	 <linux-kernel@vger.kernel.org>
Date: Mon, 20 May 2024 10:50:28 -0400
In-Reply-To: <20240518113424.13486-1-jarkko@kernel.org>
References: <20240518113424.13486-1-jarkko@kernel.org>
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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@gmail.com>
> Closes:
> https://lore.kernel.org/linux-integrity/bf67346ef623ff3c452c4f968b7d900911e250c3.camel@gmail.com/#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