xen vtpm: Initialize the comms ring with zeroes.

Initialize the ring with zeroes on the backend side and on the
frontend set the 'unused' member to zeroes.

Signed-off-by: Stefan Berger <stefanb@us.ibm.com>
linux-2.6.18-xen changeset:   374:fedc10fba9f1d5ec0c72dbcbca87e508222b4c48
linux-2.6.18-xen date:        Tue Jan 08 09:55:29 2008 +0000

diff --git a/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c b/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c
index 5488217463e581b2a9c332ffcff4d13c9a7b8bab..32ef6ef1be0fe2ffef9693c9e1a5b9d208e0dfbb 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c
+++ b/linux-2.6-xen-sparse/drivers/char/tpm/tpm_xen.c
@@ -618,6 +618,7 @@ static int tpm_xmit(struct tpm_private *tp,
                tx = &tp->tx->ring[i].req;
                tx->addr = virt_to_machine(txb->data);
                tx->size = txb->len;
+               tx->unused = 0;
 
                DPRINTK("First 4 characters sent by TPM-FE are "
                        "0x%02x 0x%02x 0x%02x 0x%02x\n",

diff --git a/linux-2.6-xen-sparse/drivers/xen/tpmback/interface.c b/linux-2.6-xen-sparse/drivers/xen/tpmback/interface.c
index 3ae227a01bbe7bfa2d4e75ae0ed0c03832b4c212..604f69eb88ed554d9738513477a529d8a05815fd 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/tpmback/interface.c
+++ b/linux-2.6-xen-sparse/drivers/xen/tpmback/interface.c
@@ -126,6 +126,7 @@ int tpmif_map(tpmif_t *tpmif, unsigned long shared_page, unsigned int evtchn)
        }
 
        tpmif->tx = (tpmif_tx_interface_t *)tpmif->tx_area->addr;
+       memset(tpmif->tx, 0, PAGE_SIZE);
 
        err = bind_interdomain_evtchn_to_irqhandler(
                tpmif->domid, evtchn, tpmif_be_int, 0, tpmif->devname, tpmif);