From: Dr. Greg Wettstein Date: Mon, 17 Sep 2018 22:53:33 +0000 (-0400) Subject: tpm: Restore functionality to xen vtpm driver. X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=e487a0f52301293152a6f8c4e217f2a11dd808e3;p=openwrt%2Fstaging%2Fblogic.git tpm: Restore functionality to xen vtpm driver. Functionality of the xen-tpmfront driver was lost secondary to the introduction of xenbus multi-page support in commit ccc9d90a9a8b ("xenbus_client: Extend interface to support multi-page ring"). In this commit pointer to location of where the shared page address is stored 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. Fixes: ccc9d90a9a8b ("xenbus_client: Extend interface to support multi-page ring") Signed-off-by: Dr. Greg Wettstein [boris: Updated commit message, added Fixes tag] Signed-off-by: Boris Ostrovsky Cc: stable@vger.kernel.org # v4.1+ Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- diff --git a/drivers/char/tpm/xen-tpmfront.c b/drivers/char/tpm/xen-tpmfront.c index 911475d36800..b150f87f38f5 100644 --- a/drivers/char/tpm/xen-tpmfront.c +++ b/drivers/char/tpm/xen-tpmfront.c @@ -264,7 +264,7 @@ 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;