I've noticed that on my Dell workstation as well as our target system when the
tboot module is executing during boot-up, the time between "TBOOT:
TPM:CreatePrimary creating hierarchy handle = 40000007" and the next line,
"TBOOT: TPM:CreatePrimary created object handle = 80000000", as shown on the
console and in the log, can vary between 12 to 48 seconds. Here's a log
snippet to demonstrate what I mean:
TBOOT: tboot: supported alg count = 2
TBOOT: tboot: hash alg = 00000004
TBOOT: tboot: hash alg = 0000000B
TBOOT: TPM:CreatePrimary creating hierarchy handle = 40000007
(system pauses here for anywhere between 12 to 48 seconds)
TBOOT: TPM:CreatePrimary created object handle = 80000000
TBOOT: TPM attribute:
TBOOT: extend policy: 2
TBOOT: current alg id: 0x4
TBOOT: timeout values: A: 750, B: 2000, C: 75000, D: 750
TBOOT: SGX:verify_IA32_se_svn_status is called
There doesn't seem to be any pattern as to how long the pause lasts, nor is
there any correlation with whether the system was just restarted (warm boot) or
started from power-off (cold boot). All other steps in the boot
process-power-on to grub, running grub, executing the kernel, etc.-require the
same (modest) times from one boot to the next. And after that second
CreatePrimary action by tboot, the rest of the tboot process consistently takes
only about 13 seconds. It looks like tboot is initializing the TPM or
something, but one would expect that to consume a consistent amount of time. I
can't tell if the hangup is on the first or second CreatePrimary call; that is,
is each line of the log created at the beginning of a step or at the end, i.e.,
is it pausing at the end of the first CreatePrimary or the beginning of the
second CreatePrimary?
Any ideas as to why there is a delay/pause at this point in booting? Why does
it vary so much? Is this a software issue or a TPM issue?
Peter
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