diff --git a/hw/s390x/css.c b/hw/s390x/css.c
index c03bb20..2bda7d0 100644
--- a/hw/s390x/css.c
+++ b/hw/s390x/css.c
@@ -20,29 +20,231 @@
 #include "hw/s390x/css.h"
 #include "trace.h"
 #include "hw/s390x/s390_flic.h"
+#include "hw/s390x/s390-virtio-ccw.h"
 
 typedef struct CrwContainer {
     CRW crw;
     QTAILQ_ENTRY(CrwContainer) sibling;
 } CrwContainer;
 
+static const VMStateDescription vmstate_crw = {
+    .name = "s390_crw",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT16(flags, CRW),
+        VMSTATE_UINT16(rsid, CRW),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
+static const VMStateDescription vmstate_crw_container = {
+    .name = "s390_crw_container",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_STRUCT(crw, CrwContainer, 0, vmstate_crw, CRW),
+        VMSTATE_END_OF_LIST()
+    },
+};
+
 typedef struct ChpInfo {
     uint8_t in_use;
     uint8_t type;
     uint8_t is_virtual;
 } ChpInfo;
 
+static const VMStateDescription vmstate_chp_info = {
+    .name = "s390_chp_info",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(in_use, ChpInfo),
+        VMSTATE_UINT8(type, ChpInfo),
+        VMSTATE_UINT8(is_virtual, ChpInfo),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 typedef struct SubchSet {
     SubchDev *sch[MAX_SCHID + 1];
     unsigned long schids_used[BITS_TO_LONGS(MAX_SCHID + 1)];
     unsigned long devnos_used[BITS_TO_LONGS(MAX_SCHID + 1)];
 } SubchSet;
 
+static const VMStateDescription vmstate_scsw = {
+    .name = "s390_scsw",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT16(flags, SCSW),
+        VMSTATE_UINT16(ctrl, SCSW),
+        VMSTATE_UINT32(cpa, SCSW),
+        VMSTATE_UINT8(dstat, SCSW),
+        VMSTATE_UINT8(cstat, SCSW),
+        VMSTATE_UINT16(count, SCSW),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_pmcw = {
+    .name = "s390_pmcw",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(intparm, PMCW),
+        VMSTATE_UINT16(flags, PMCW),
+        VMSTATE_UINT16(devno, PMCW),
+        VMSTATE_UINT8(lpm, PMCW),
+        VMSTATE_UINT8(pnom, PMCW),
+        VMSTATE_UINT8(lpum, PMCW),
+        VMSTATE_UINT8(pim, PMCW),
+        VMSTATE_UINT16(mbi, PMCW),
+        VMSTATE_UINT8(pom, PMCW),
+        VMSTATE_UINT8(pam, PMCW),
+        VMSTATE_UINT8_ARRAY(chpid, PMCW, 8),
+        VMSTATE_UINT32(chars, PMCW),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_schib = {
+    .name = "s390_schib",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_STRUCT(pmcw, SCHIB, 0, vmstate_pmcw, PMCW),
+        VMSTATE_STRUCT(scsw, SCHIB, 0, vmstate_scsw, SCSW),
+        VMSTATE_UINT64(mba, SCHIB),
+        VMSTATE_UINT8_ARRAY(mda, SCHIB, 4),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+
+static const VMStateDescription vmstate_ccw1 = {
+    .name = "s390_ccw1",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(cmd_code, CCW1),
+        VMSTATE_UINT8(flags, CCW1),
+        VMSTATE_UINT16(count, CCW1),
+        VMSTATE_UINT32(cda, CCW1),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_ciw = {
+    .name = "s390_ciw",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(type, CIW),
+        VMSTATE_UINT8(command, CIW),
+        VMSTATE_UINT16(count, CIW),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static const VMStateDescription vmstate_sense_id = {
+    .name = "s390_sense_id",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(reserved, SenseId),
+        VMSTATE_UINT16(cu_type, SenseId),
+        VMSTATE_UINT8(cu_model, SenseId),
+        VMSTATE_UINT16(dev_type, SenseId),
+        VMSTATE_UINT8(dev_model, SenseId),
+        VMSTATE_UINT8(unused, SenseId),
+        VMSTATE_STRUCT_ARRAY(ciw, SenseId, MAX_CIWS, 0, vmstate_ciw, CIW),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static int subch_dev_post_load(void *opaque, int version_id);
+static void subch_dev_pre_save(void *opaque);
+
+const VMStateDescription vmstate_subch_dev = {
+    .name = "s390_subch_dev",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .post_load = subch_dev_post_load,
+    .pre_save = subch_dev_pre_save,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8_EQUAL(cssid, SubchDev),
+        VMSTATE_UINT8_EQUAL(ssid, SubchDev),
+        VMSTATE_UINT16(migrated_schid, SubchDev),
+        VMSTATE_UINT16_EQUAL(devno, SubchDev),
+        VMSTATE_BOOL(thinint_active, SubchDev),
+        VMSTATE_STRUCT(curr_status, SubchDev, 0, vmstate_schib, SCHIB),
+        VMSTATE_UINT8_ARRAY(sense_data, SubchDev, 32),
+        VMSTATE_UINT64(channel_prog, SubchDev),
+        VMSTATE_STRUCT(last_cmd, SubchDev, 0, vmstate_ccw1, CCW1),
+        VMSTATE_BOOL(last_cmd_valid, SubchDev),
+        VMSTATE_STRUCT(id, SubchDev, 0, vmstate_sense_id, SenseId),
+        VMSTATE_BOOL(ccw_fmt_1, SubchDev),
+        VMSTATE_UINT8(ccw_no_data_cnt, SubchDev),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static int css_get_ind_addr(QEMUFile *f, void *pv, size_t size,
+                            VMStateField *field)
+{
+    int32_t len;
+    IndAddr **ind_addr = pv;
+
+    len = qemu_get_be32(f);
+    if (len != 0) {
+        *ind_addr = get_indicator(qemu_get_be64(f), len);
+    } else {
+        qemu_get_be64(f);
+        *ind_addr = NULL;
+    }
+    return 0;
+}
+
+static int css_put_ind_addr(QEMUFile *f, void *pv, size_t size,
+                            VMStateField *field, QJSON *vmdesc)
+{
+    IndAddr *ind_addr = *(IndAddr **) pv;
+
+    if (ind_addr != NULL) {
+        qemu_put_be32(f, ind_addr->len);
+        qemu_put_be64(f, ind_addr->addr);
+    } else {
+        qemu_put_be32(f, 0);
+        qemu_put_be64(f, 0UL);
+    }
+    return 0;
+}
+
+const VMStateInfo vmstate_info_ind_addr = {
+    .name = "s390_ind_addr",
+    .get = css_get_ind_addr,
+    .put = css_put_ind_addr
+};
+
 typedef struct CssImage {
     SubchSet *sch_set[MAX_SSID + 1];
     ChpInfo chpids[MAX_CHPID + 1];
 } CssImage;
 
+static const VMStateDescription vmstate_css_img = {
+    .name = "s390_css_img",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        /* Subchannel sets have no relevant state. */
+        VMSTATE_STRUCT_ARRAY(chpids, CssImage, MAX_CHPID + 1, 0,
+                             vmstate_chp_info, ChpInfo),
+        VMSTATE_END_OF_LIST()
+    }
+
+};
+
 typedef struct IoAdapter {
     uint32_t id;
     uint8_t type;
@@ -60,10 +262,34 @@ typedef struct ChannelSubSys {
     uint64_t chnmon_area;
     CssImage *css[MAX_CSSID + 1];
     uint8_t default_cssid;
+    /* don't migrate */
     IoAdapter *io_adapters[CSS_IO_ADAPTER_TYPE_NUMS][MAX_ISC + 1];
+    /* don't migrate */
     QTAILQ_HEAD(, IndAddr) indicator_addresses;
 } ChannelSubSys;
 
+static const VMStateDescription vmstate_css = {
+    .name = "s390_css",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (VMStateField[]) {
+        VMSTATE_QTAILQ_V(pending_crws, ChannelSubSys, 1, vmstate_crw_container,
+                         CrwContainer, sibling),
+        VMSTATE_BOOL(sei_pending, ChannelSubSys),
+        VMSTATE_BOOL(do_crw_mchk, ChannelSubSys),
+        VMSTATE_BOOL(crws_lost, ChannelSubSys),
+        /* These were kind of migrated by virtio */
+        VMSTATE_UINT8(max_cssid, ChannelSubSys),
+        VMSTATE_UINT8(max_ssid, ChannelSubSys),
+        VMSTATE_BOOL(chnmon_active, ChannelSubSys),
+        VMSTATE_UINT64(chnmon_area, ChannelSubSys),
+        VMSTATE_ARRAY_OF_POINTER_TO_STRUCT(css, ChannelSubSys, MAX_CSSID + 1,
+                0, vmstate_css_img, CssImage),
+        VMSTATE_UINT8(default_cssid, ChannelSubSys),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
 static ChannelSubSys channel_subsys = {
     .pending_crws = QTAILQ_HEAD_INITIALIZER(channel_subsys.pending_crws),
     .do_crw_mchk = true,
@@ -75,6 +301,56 @@ static ChannelSubSys channel_subsys = {
         QTAILQ_HEAD_INITIALIZER(channel_subsys.indicator_addresses),
 };
 
+static void subch_dev_pre_save(void *opaque)
+{
+    SubchDev *s = opaque;
+
+    /* Prepare remote_schid for save */
+    s->migrated_schid = s->schid;
+}
+
+static int subch_dev_post_load(void *opaque, int version_id)
+{
+
+    SubchDev *s = opaque;
+
+    /* Re-assign the subchannel to remote_schid if necessary */
+    if (s->migrated_schid != s->schid) {
+        if (css_find_subch(true, s->cssid, s->ssid, s->schid) == s) {
+            /*
+             * Cleanup the slot before moving to s->migrated_schid provided
+             * it still belongs to us, i.e. it was not changed by previous
+             * invocation of this function.
+             */
+            css_subch_assign(s->cssid, s->ssid, s->schid, s->devno, NULL);
+        }
+        /* It's OK to re-assign without a prior de-assign. */
+        s->schid = s->migrated_schid;
+        css_subch_assign(s->cssid, s->ssid, s->schid, s->devno, s);
+    }
+
+    if (css_migration_enabled()) {
+        /* No compat voodoo to do ;) */
+        return 0;
+    }
+    /*
+     * Hack alert. If we don't migrate the channel subsystem status
+     * we still 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;
+}
+
 IndAddr *get_indicator(hwaddr ind_addr, int len)
 {
     IndAddr *indicator;
diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h
index f1f0d7f..6a451b2 100644
--- a/include/hw/s390x/css.h
+++ b/include/hw/s390x/css.h
@@ -87,6 +87,7 @@ struct SubchDev {
     bool ccw_fmt_1;
     bool thinint_active;
     uint8_t ccw_no_data_cnt;
+    uint16_t migrated_schid; /* used for missmatch detection */
     /* transport-provided data: */
     int (*ccw_cb) (SubchDev *, CCW1);
     void (*disable_cb)(SubchDev *);
@@ -94,14 +95,21 @@ struct SubchDev {
     void *driver_data;
 };
 
+extern const VMStateDescription vmstate_subch_dev;
+
 typedef struct IndAddr {
     hwaddr addr;
     uint64_t map;
     unsigned long refcnt;
-    int len;
+    int32_t len;
     QTAILQ_ENTRY(IndAddr) sibling;
 } IndAddr;
 
+extern const VMStateInfo vmstate_info_ind_addr;
+
+#define VMSTATE_PTR_TO_IND_ADDR(_f, _s)                                   \
+    VMSTATE_SINGLE(_f, _s, 1 , vmstate_info_ind_addr, IndAddr*)
+
 IndAddr *get_indicator(hwaddr ind_addr, int len);
 void release_indicator(AdapterInfo *adapter, IndAddr *indicator);
 int map_indicator(AdapterInfo *adapter, IndAddr *indicator);
