Functionality of the xen-tpmfront driver was lost secondary to the introduction of xenbus multi-page support in the following commit: ccc9d90a9a8b5c4ad7e9708ec41f75ff9e98d61d xenbus_client: Extend interface to support multi-page ring In this commit a pointer to the shared page address was being passed to the xenbus_grant_ring() function rather then the address of the shared page itself. This resulted in a situation where the driver would attach to the vtpm-stubdom but any attempt to send a command to the stub domain would timeout. A diagnostic finding for this regression is the following error message being generated when the xen-tpmfront driver probes for a device: <3>vtpm vtpm-0: tpm_transmit: tpm_send: error -62 <3>vtpm vtpm-0: A TPM error (-62) occurred attempting to determine the timeouts This fix is relevant to all kernels from 4.1 forward which is the release in which multi-page xenbus support was introduced. Daniel De Graaf formulated the fix by code inspection after the regression point was located. Signed-off-by: Dr. Greg Wettstein <greg@xxxxxxxxxxxx> --- drivers/char/tpm/xen-tpmfront.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/char/tpm/xen-tpmfront.c b/drivers/char/tpm/xen-tpmfront.c index 5aaa268..dd83a07 100644 --- a/drivers/char/tpm/xen-tpmfront.c +++ b/drivers/char/tpm/xen-tpmfront.c @@ -203,7 +203,7 @@ static int setup_ring(struct xenbus_device *dev, struct tpm_private *priv) return -ENOMEM; } - rv = xenbus_grant_ring(dev, &priv->shr, 1, &gref); + rv = xenbus_grant_ring(dev, priv->shr, 1, &gref); if (rv < 0) return rv; -- 2.2.2 -- -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html