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H A Dtpm_ibmvtpm.cdiff 72d0556dca39f45eca6c4c085e9eb0fc70aec025 Fri Jun 19 05:30:40 CEST 2020 David Gibson <david@gibson.dropbear.id.au> tpm: ibmvtpm: Wait for ready buffer before probing for TPM2 attributes

The tpm2_get_cc_attrs_tbl() call will result in TPM commands being issued,
which will need the use of the internal command/response buffer. But,
we're issuing this *before* we've waited to make sure that buffer is
allocated.

This can result in intermittent failures to probe if the hypervisor / TPM
implementation doesn't respond quickly enough. I find it fails almost
every time with an 8 vcpu guest under KVM with software emulated TPM.

To fix it, just move the tpm2_get_cc_attrs_tlb() call after the
existing code to wait for initialization, which will ensure the buffer
is allocated.

Fixes: 18b3670d79ae9 ("tpm: ibmvtpm: Add support for TPM2")
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>