On 01/20/2017 10:00 AM, Dr. Greg Wettstein wrote: > 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. > > Cc: <[email protected]> # 4.1-
4.1+, I believe. > Suggested-by: Daniel De Graaf <[email protected]> > Signed-off-by: Dr. Greg Wettstein <[email protected]> Reviewed-by: Boris Ostrovsky <[email protected]> > --- > 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 3111f2778079..d1478f7b3f97 100644 > --- a/drivers/char/tpm/xen-tpmfront.c > +++ b/drivers/char/tpm/xen-tpmfront.c > @@ -201,7 +201,7 @@ 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; >
