Commit 797b6086 authored by Halil Pasic's avatar Halil Pasic Committed by Cornelia Huck
Browse files

virtio-ccw: Check the number of vqs in CCW_CMD_SET_IND 



We cannot support more than 64 virtqueues with the 64 bits provided by
classic indicators. If a driver tries to setup classic indicators
(which it is free to do even for virtio-1 devices) for a device with
more than 64 virtqueues, we should reject the attempt so that the
driver does not end up with an unusable device.

This is in preparation for bumping the number of supported virtqueues
on the ccw transport.

Signed-off-by: default avatarHalil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent d2256070

hw/s390x/virtio-ccw.c

+7 −0
Original line number Diff line number Diff line
@@ -35,6 +35,8 @@ 
#include "trace.h"

#include "hw/s390x/css-bridge.h"



#define NR_CLASSIC_INDICATOR_BITS 64



static void virtio_ccw_bus_new(VirtioBusState *bus, size_t bus_size,

                               VirtioCcwDevice *dev);
@@ -509,6 +511,11 @@ static int virtio_ccw_cb(SubchDev *sch, CCW1 ccw) 
            ret = -ENOSYS;

            break;

        }

        if (virtio_get_num_queues(vdev) > NR_CLASSIC_INDICATOR_BITS) {

            /* More queues than indicator bits --> trigger a reject */

            ret = -ENOSYS;

            break;

        }

        if (!ccw.cda) {

            ret = -EFAULT;

        } else {