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Date:   Thu, 1 Apr 2021 15:17:45 +0200 (CEST)
From:   Richard Weinberger <richard@nod.at>
To:     Sumit Garg <sumit.garg@linaro.org>
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        Jarkko Sakkinen <jarkko@kernel.org>,
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Subject: Re: [PATCH v1 0/3] KEYS: trusted: Introduce support for NXP
 CAAM-based trusted keys
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Thread-Topic: KEYS: trusted: Introduce support for NXP CAAM-based trusted keys
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Sumit,

----- Ursprüngliche Mail -----
> Von: "Sumit Garg" <sumit.garg@linaro.org>
> IIUC, this would require support for multiple trusted keys backends at
> runtime but currently the trusted keys subsystem only supports a
> single backend which is selected via kernel module parameter during
> boot.
> 
> So the trusted keys framework needs to evolve to support multiple
> trust sources at runtime but I would like to understand the use-cases
> first. IMO, selecting the best trust source available on a platform
> for trusted keys should be a one time operation, so why do we need to
> have other backends available at runtime as well?

I thought about devices with a TPM-Chip and CAAM.
IMHO allowing only one backend at the same time is a little over simplified. 

Thanks,
//richard