qemu/hw/core
Michael S. Tsirkin 04920fc0fa loader: store FW CFG ROM files in RAM
ROM files that are put in FW CFG are copied to guest ram, by BIOS, but
they are not backed by RAM so they don't get migrated.

Each time we change two bytes in such a ROM this breaks cross-version
migration: since we can migrate after BIOS has read the first byte but
before it has read the second one, getting an inconsistent state.

Future-proof this by creating, for each such ROM,
an MR serving as the backing store.
This MR is never mapped into guest memory, but it's registered
as RAM so it's migrated with the guest.

Naturally, this only helps for -M 1.7 and up, older machine types
will still have the cross-version migration bug.
Luckily the race window for the problem to trigger is very small,
which is also likely why we didn't notice the cross-version
migration bug in testing yet.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
2013-08-21 00:18:39 +03:00
..
empty_slot.c empty_slot: QOM cast cleanup 2013-07-29 21:06:37 +02:00
irq.c hw: move target-independent files to subdirectories 2013-04-08 18:13:12 +02:00
loader.c loader: store FW CFG ROM files in RAM 2013-08-21 00:18:39 +03:00
Makefile.objs qdev: Drop taddr properties 2013-04-20 17:54:52 +00:00
null-machine.c hw: move target-independent files to subdirectories 2013-04-08 18:13:12 +02:00
ptimer.c hw: move target-independent files to subdirectories 2013-04-08 18:13:12 +02:00
qdev-properties-system.c sysemu: avoid proliferation of include/ subdirectories 2013-04-15 18:19:25 +02:00
qdev-properties.c qdev: Use clz in print_size 2013-07-31 07:54:21 -05:00
qdev.c qdev: Set globals in instance_post_init function 2013-08-16 18:44:33 +02:00
stream.c stream: Remove app argument hack 2013-04-16 10:04:23 +02:00
sysbus.c hw: move target-independent files to subdirectories 2013-04-08 18:13:12 +02:00
uboot_image.h hw: move private headers to hw/ subdirectories. 2013-04-08 18:13:16 +02:00