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SubjectRe: [PATCHv2] tpm: ibmvtpm: Wait for ready buffer before probing for TPM2 attributes
On Fri, Jun 19, 2020 at 01:30:40PM +1000, David Gibson wrote:
> 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: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>

/Jarkko

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