migrate: Introduce zero RAM checks to skip RAM migration

Migration of a "none" machine with no RAM crashes abruptly as
bitmap_new() fails and thus aborts. Instead place zero RAM checks at
appropriate places to skip migration of RAM in this case and complete
migration successfully for devices only.

Signed-off-by: Ashijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1486564125-31366-1-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
Ashijeet Acharya 2017-02-08 19:58:45 +05:30 committed by Dr. David Alan Gilbert
parent ced1c6166e
commit 0827b9e97d

View File

@ -1346,6 +1346,11 @@ static int ram_find_and_save_block(QEMUFile *f, bool last_stage,
ram_addr_t dirty_ram_abs; /* Address of the start of the dirty page in
ram_addr_t space */
/* No dirty page as there is zero RAM */
if (!ram_bytes_total()) {
return pages;
}
pss.block = last_seen_block;
pss.offset = last_offset;
pss.complete_round = false;
@ -1952,14 +1957,17 @@ static int ram_save_init_globals(void)
bytes_transferred = 0;
reset_ram_globals();
ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS;
migration_bitmap_rcu = g_new0(struct BitmapRcu, 1);
migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages);
bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages);
/* Skip setting bitmap if there is no RAM */
if (ram_bytes_total()) {
ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS;
migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages);
bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages);
if (migrate_postcopy_ram()) {
migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages);
bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages);
if (migrate_postcopy_ram()) {
migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages);
bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages);
}
}
/*