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    SubjectRe: 5.3 boot regression caused by 5.3 TPM changes
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    Hi,

    On 04-08-19 17:33, Ard Biesheuvel wrote:
    > Hi Hans,
    >
    > On Sun, 4 Aug 2019 at 13:00, Hans de Goede <hdegoede@redhat.com> wrote:
    >>
    >> Hi All,
    >>
    >> While testing 5.3-rc2 on an Irbis TW90 Intel Cherry Trail based
    >> tablet I noticed that it does not boot on this device.
    >>
    >> A git bisect points to commit 166a2809d65b ("tpm: Don't duplicate
    >> events from the final event log in the TCG2 log")
    >>
    >> And I can confirm that reverting just that single commit makes
    >> the TW90 boot again.
    >>
    >> This machine uses AptIO firmware with base component versions
    >> of: UEFI 2.4 PI 1.3. I've tried to reproduce the problem on
    >> a Teclast X80 Pro which is also CHT based and also uses AptIO
    >> firmware with the same base components. But it does not reproduce
    >> there. Neither does the problem reproduce on a CHT tablet using
    >> InsideH20 based firmware.
    >>
    >> Note that these devices have a software/firmware TPM-2.0
    >> implementation, they do not have an actual TPM chip.
    >>
    >> Comparing TPM firmware setting between the 2 AptIO based
    >> tablets the settings are identical, but the troublesome
    >> TW90 does have some more setting then the X80, it has
    >> the following settings which are not shown on the X80:
    >>
    >> Active PCR banks: SHA-1 (read only)
    >> Available PCR banks: SHA-1,SHA256 (read only)
    >> TPM2.0 UEFI SPEC version: TCG_2 (other possible setting: TCG_1_2
    >> Physical Presence SPEC ver: 1.2 (other possible setting: 1.3)
    >>
    >> I have the feeling that at least the first 2 indicate that
    >> the previous win10 installation has actually used the
    >> TPM, where as on the X80 the TPM is uninitialized.
    >> Note this is just a hunch I could be completely wrong.
    >>
    >> I would be happy to run any commands to try and debug this
    >> or to build a kernel with some patches to gather more info.
    >>
    >> Note any kernel patches to printk some debug stuff need
    >> to be based on 5.3 with 166a2809d65b reverted, without that
    >> reverted the device will not boot, and thus I cannot collect
    >> logs without it reverted.
    >>
    >
    > Are you booting a 64-bit kernel on 32-bit firmware?

    Yes you are right, I must say that this is somewhat surprising
    most Cherry Trail devices do use 64 bit firmware (where as Bay Trail
    typically uses 32 bit). But I just checked efibootmgr output and it
    says it is booting: \EFI\FEDORA\SHIMIA32.EFI so yeah 32 bit firmware.

    Recent Fedora releases take care of this so seamlessly I did not
    even realize...

    Regards,

    Hans

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