Re: [PATCH] ima: remove ACPI dependency

David Safford
2009-10-27T15:59:47Z

On Tue, 2009-10-27 at 09:58 -0400, Eric Paris wrote:
> On Mon, Oct 26, 2009 at 9:26 AM, Mimi Zohar <zohar@linux.vnet.ibm.com> wrote:
> > Remove ACPI dependency on systems without a TPM enabled.
>
> I'm confused why you need ACPI at all. The TPM code doesn't require
> ACPI (I wish it did but Alan Cox Nak'd that patch). I don't see acpi
> anywhere in the ima code. What's the problem we are solving? Why
> does IMA care about ACPI at all? And aren't you really just dropping
> the build requirement on TCG_TPM? Is that a great idea?
>
> -Eric

This is discussed in the LSM thread:
http://marc.info/?l=linux-security-module&m=125322062401677&w=2

Basically, if running on a system with a TPM, IMA wants the TPM
boot measurement log, which the TPM driver can only get through
ACPI. If the platform does not have a TPM, then IMA does not
need ACPI.

dave