Re: [PATCH] crypto: ccp: Load the firmware twice when SEV API version < 1.43

From: Jarkko Sakkinen
Date: Sat Aug 06 2022 - 14:15:29 EST


On Thu, Aug 04, 2022 at 03:37:20PM +0200, Harald Hoyer wrote:
> Am 04.08.22 um 15:13 schrieb Tom Lendacky:
> > On 8/3/22 20:02, Jarkko Sakkinen wrote:
> > > From: Jarkko Sakkinen <jarkko@xxxxxxxxxxx>
> > >
> > > SEV-SNP does not initialize to a legit state, unless the firmware is
> > > loaded twice, when SEP API version < 1.43, and the firmware is updated
> > > to a later version. Because of this user space needs to work around
> > > this with "rmmod && modprobe" combo. Fix this by implementing the
> > > workaround to the driver.
> >
> > The SNP hypervisor patches are placing a minimum supported version
> > requirement for the SEV firmware that exceeds the specified version
> > above [1] (for the reason above, as well as some others), so this patch
> > is not needed, NAK.
>
> As described in the "Milan Release Notes.txt" of the AMD firmware update package amd_sev_fam19h_model0xh_1.33.03.zip.
>
> "If upgrading to 1.33.01 or later from something older (picking up
> CSF-1201), it is required that two Download Firmware commands be run to fix
> the "Committed Version" across the firmware. CSF-1201 fixed a bug where the
> committed version in the attestation report was incorrect. Performing a
> single Download Firmware will upgrade the firmware, but performing a second
> one will correct the committed version. This is a one-time upgrade issue.
> "

Reference should be part of the commit message. I'll
update for the next iteration. Thanks for the remark.

BR, Jarkko