Commit 72d0556d authored by David Gibson's avatar David Gibson Committed by Jarkko Sakkinen

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: 18b3670d ("tpm: ibmvtpm: Add support for TPM2")
Signed-off-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
parent 82efeb16
...@@ -683,13 +683,6 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, ...@@ -683,13 +683,6 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
if (rc) if (rc)
goto init_irq_cleanup; goto init_irq_cleanup;
if (!strcmp(id->compat, "IBM,vtpm20")) {
chip->flags |= TPM_CHIP_FLAG_TPM2;
rc = tpm2_get_cc_attrs_tbl(chip);
if (rc)
goto init_irq_cleanup;
}
if (!wait_event_timeout(ibmvtpm->crq_queue.wq, if (!wait_event_timeout(ibmvtpm->crq_queue.wq,
ibmvtpm->rtce_buf != NULL, ibmvtpm->rtce_buf != NULL,
HZ)) { HZ)) {
...@@ -697,6 +690,13 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, ...@@ -697,6 +690,13 @@ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
goto init_irq_cleanup; goto init_irq_cleanup;
} }
if (!strcmp(id->compat, "IBM,vtpm20")) {
chip->flags |= TPM_CHIP_FLAG_TPM2;
rc = tpm2_get_cc_attrs_tbl(chip);
if (rc)
goto init_irq_cleanup;
}
return tpm_chip_register(chip); return tpm_chip_register(chip);
init_irq_cleanup: init_irq_cleanup:
do { do {
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment