Commit ec7353a1 authored by Cornelia Huck's avatar Cornelia Huck
Browse files

css: mss/mcss-e vs. migration 



Our main channel_subsys structure is not a device (yet), but we need
to setup mss/mcss-e again if the guest had enabled it before. Use
a hack that should catch most configurations (assuming that the guest
will have enabled at least one device in higher subchannel sets or
channel subsystems if it enabled the functionality.)

Signed-off-by: default avatarCornelia Huck <cornelia.huck@de.ibm.com>
parent fa8b0ca5

hw/s390x/css.c

+15 −0
Original line number Diff line number Diff line
@@ -1464,6 +1464,21 @@ int subch_device_load(SubchDev *s, QEMUFile *f) 
    }

    s->ccw_fmt_1 = qemu_get_byte(f);

    s->ccw_no_data_cnt = qemu_get_byte(f);

    /*

     * Hack alert. We don't migrate the channel subsystem status (no

     * device!), but we need to find out if the guest enabled mss/mcss-e.

     * If the subchannel is enabled, it certainly was able to access it,

     * so adjust the max_ssid/max_cssid values for relevant ssid/cssid

     * values. This is not watertight, but better than nothing.

     */

    if (s->curr_status.pmcw.flags & PMCW_FLAGS_MASK_ENA) {

        if (s->ssid) {

            channel_subsys->max_ssid = MAX_SSID;

        }

        if (s->cssid != channel_subsys->default_cssid) {

            channel_subsys->max_cssid = MAX_CSSID;

        }

    }

    return 0;

}