Re: [PATCH] tpm_crb: fix fTPM on AMD Zen+ CPUs
From: Jarkko Sakkinen
Date: Sat Sep 07 2019 - 19:58:33 EST
On Sun, 2019-09-08 at 00:49 +0300, Jarkko Sakkinen wrote:
> On Wed, 2019-09-04 at 22:03 +0300, ivan.lazeev@xxxxxxxxx wrote:
> > From: Ivan Lazeev <ivan.lazeev@xxxxxxxxx>
> >
> > Bug link: https://bugzilla.kernel.org/show_bug.cgi?id=195657
> >
> > cmd/rsp buffers are expected to be in the same ACPI region.
> > For Zen+ CPUs BIOS's might report two different regions, some of
> > them also report region sizes inconsistent with values from TPM
> > registers.
> >
> > Work around the issue by storing ACPI regions declared for the
> > device in a list, then using it to find entry corresponding
> > to each buffer. Use information from the entry to map each resource
> > at most once and make buffer size consistent with the length of the
> > region.
> >
> > Signed-off-by: Ivan Lazeev <ivan.lazeev@xxxxxxxxx>
>
> Can you add the relevant pieces of /proc/iomem output to the commit
> message so we can see the memory configuration? I don't have the
> hardware available where this kind of situation occurs.
Here in particular this is more than relevant because given that this
patch fixes the issue for you, it seems that you don't have the regions
marked as NVS regions.
/Jarkko