Commit 0827b9e9 authored by Ashijeet Acharya's avatar Ashijeet Acharya Committed by Dr. David Alan Gilbert
Browse files

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: default avatarAshijeet Acharya <ashijeetacharya@gmail.com>
Message-Id: <1486564125-31366-1-git-send-email-ashijeetacharya@gmail.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: default avatarPhilippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
parent ced1c616

migration/ram.c

+15 −7
Original line number Diff line number Diff line
@@ -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;
@@ -1952,8 +1957,10 @@ 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);

    /* 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);
@@ -1961,6 +1968,7 @@ static int ram_save_init_globals(void) 
            migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages);

            bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages);

        }

    }



    /*

     * Count the total number of pages used by ram blocks not including any