Re: tpm_tis TPM2.0 not detected on cold boot

[Mimi Zohar <zohar@linux.ibm.com>]

On Tue, 2019-01-01 at 17:15 +0100, Michael Niewöhner wrote:
> On Mon, 2018-12-31 at 16:17 -0500, Mimi Zohar wrote:
> > On Sun, 2018-12-30 at 14:22 +0100, Michael Niewöhner wrote:
> > 
> > > > difference is that on a cold boot, the TPM takes longer to initialize.
> > > 
> > > Well, as I said. Waiting for 10, 20 or even 60 seconds in the boot manager
> > > does
> > > not solve the problem. So the problem is NOT that the TPM takes longer to
> > > initialize. Even adding a delay of 20 seconds before TPM init does not solve
> > > that while that should be more than enough time.
> > 
> > The purpose of commenting out the TPM2 selftest was to minimize the
> > TPM initialization delay, so that the TPM is ready before IMA.  After
> > James' patch that wasn't needed anymore.
> > 
> > Looking back at this thread, I see you're using systemd-boot, not
> > grub2.  When you commented out the systemd-boot timeout, IMA found the
> > TPM.  The question is why isn't the TPM ready with the timeout before
> > IMA (like above)?  Has systemd-boot done the selftest?
> 
> I am not sure wether systemd-boot touches TPM at all but I get the same
> behaviour with syslinux-efi.

From looking at the source code, it depends on whether systemd was
compiled with ENABLE_TPM enabled(eg. src/boot/efi/boot.c,
src/boot/efi/measure.c, src/boot/efi/stub.c).

Mimi