On 2/25/2025 11:36 AM, David Hildenbrand wrote:
+ * Return true if ram is compatible with CPR. Do not exclude rom,
+ * because the rom file could change in new QEMU.
+ */
+static bool ram_is_cpr_compatible(RAMBlock *rb)
+{
+ MemoryRegion *mr = rb->mr;
+
+ if (!mr || !memory_region_is_ram(mr)) {
+ return true;
+ }
+
+ /* Ram device is remapped in new QEMU */
+ if (memory_region_is_ram_device(mr)) {
+ return true;
+ }
+
+ /* Named files are remapped in new QEMU, same contents if shared (no COW)
*/
+ if (qemu_ram_is_shared(rb) && qemu_ram_is_named_file(rb)) {
+ return true;
+ }
In general
Reviewed-by: David Hildenbrand <da...@redhat.com>
just one more question:
+
+ /* A file descriptor is remapped in new QEMU */
+ if (rb->fd >= 0) {
+ return true;
This looks odd / wrong. Assume we have
!qemu_ram_is_shared(rb) || !qemu_ram_is_named_file(rb)
(negated condition above)
Why should having a fd be fine? It could just be MAP_PRIVATE/COW (which you
document above) or an unnamed file?
Thank-you, that is a bug. I will send V4 with
/* A shared file descriptor is remapped in new QEMU */
if (rb->fd >= 0 && qemu_ram_is_shared(rb)) {
return true;
}
- Steve
