On Thu, 2026-03-05 at 00:23 +0300, Vladimir Sementsov-Ogievskiy wrote:
> That's the only usage through the whole base. Doesn't
> worth keeping the whole complexity. And 2.7 machines were
> long ago.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
> ---
> hw/s390x/css.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)
Agreed that the two "Bug!" hints aren't helpful, and the devno hint is probably offering more
confusion than anything else.
Reviewed-by: Eric Farman <farman@linux.ibm.com>
>
> diff --git a/hw/s390x/css.c b/hw/s390x/css.c
> index 04ce3178a0b..df5f0bc27f1 100644
> --- a/hw/s390x/css.c
> +++ b/hw/s390x/css.c
> @@ -192,10 +192,6 @@ static const VMStateDescription vmstate_schdev_orb = {
> static int subch_dev_post_load(void *opaque, int version_id);
> static int subch_dev_pre_save(void *opaque);
>
> -const char err_hint_devno[] = "Devno mismatch, tried to load wrong section!"
> - " Likely reason: some sequences of plug and unplug can break"
> - " migration for machine versions prior to 2.7 (known design flaw).";
> -
> const VMStateDescription vmstate_subch_dev = {
> .name = "s390_subch_dev",
> .version_id = 1,
> @@ -203,10 +199,15 @@ const VMStateDescription vmstate_subch_dev = {
> .post_load = subch_dev_post_load,
> .pre_save = subch_dev_pre_save,
> .fields = (const VMStateField[]) {
> - VMSTATE_UINT8_EQUAL(cssid, SubchDev, "Bug!"),
> - VMSTATE_UINT8_EQUAL(ssid, SubchDev, "Bug!"),
> + VMSTATE_UINT8_EQUAL(cssid, SubchDev, NULL),
> + VMSTATE_UINT8_EQUAL(ssid, SubchDev, NULL),
> VMSTATE_UINT16(migrated_schid, SubchDev),
> - VMSTATE_UINT16_EQUAL(devno, SubchDev, err_hint_devno),
> + /*
> + * If devno mismatch on target, it may be due to some
> + * sequences of plug and unplug breaks migration for
> + * machine versions prior to 2.7 (known design flaw).
> + */
> + VMSTATE_UINT16_EQUAL(devno, SubchDev, NULL),
> VMSTATE_BOOL(thinint_active, SubchDev),
> VMSTATE_STRUCT(curr_status, SubchDev, 0, vmstate_schib, SCHIB),
> VMSTATE_UINT8_ARRAY(sense_data, SubchDev, 32),