@samitouri / QOSamiQemu / commits / 33db64cf28

hw/ide: restore the power-on device state before loading

Loading a snapshot reuses the IDEState of the machine it is loaded into: load_snapshot() resets the machine and then feeds the stream into the existing devices. The reset does not help, as ide_reset() restores the logical CHS translation only when the guest asked for power-on defaults to be reverted with SET FEATURES 0xCC. A guest that replaced the translation with INITIALIZE DEVICE PARAMETERS therefore keeps it across the load of a snapshot taken before it did, while the restored guest expects the geometry of that moment. Every CHS access then lands on a sector other than the one asked for, with no error reported. s->reset_reverts survives a load the same way. Add a pre_load restoring the defaults, which docs/devel/migration/main.rst recommends for state a stream need not carry, and which the following subsections rely on. The RESET_TYPE_SNAPSHOT_LOAD marking that reset would be another way to recognise the case, but no IDE controller can see it while they all use device_class_set_legacy_reset(). Cc: John Snow <jsnow@redhat.com> Cc: Peter Maydell <peter.maydell@linaro.org> Cc: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com> Fixes: 176e4961bb33 ("hw/ide/core.c: Implement ATA INITIALIZE_DEVICE_PARAMETERS command") Signed-off-by: Denis V. Lunev <den@openvz.org>

Denis V. Lunev committed Aug 4, 2026 at 18:34 UTC 33db64cf28829103e6b60905666082a01d011fc8

1 file changed +13

hw/ide/core.c

+13

@@ -2863,6 +2863,18 @@ static int transfer_end_table_idx(EndTransferFunc *fn)

2863 return -1;

2864 }

2865

2866 +static int ide_drive_pre_load(void *opaque)

2867 +{

2868 + IDEState *s = opaque;

2869 +

2870 + /* The subsections below are sent only where the guest replaced these */

2871 + s->heads = s->drive_heads;

2872 + s->sectors = s->drive_sectors;

2873 + s->reset_reverts = false;

2874 +

2875 + return 0;

2876 +}

2877 +

2878 static int ide_drive_post_load(void *opaque, int version_id)

2879 {

2880 IDEState *s = opaque;

@@ -2986,6 +2998,7 @@ const VMStateDescription vmstate_ide_drive = {

2998 .name = "ide_drive",

2999 .version_id = 3,

3000 .minimum_version_id = 0,

3001 + .pre_load = ide_drive_pre_load,

3002 .post_load = ide_drive_post_load,

3003 .fields = (const VMStateField[]) {

3004 VMSTATE_INT32(mult_sectors, IDEState),