Commit 1499ab09 authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by Eric Blake
Browse files

migration/block-dirty-bitmap: cancel migration on shutdown 



If target is turned off prior to postcopy finished, target crashes
because busy bitmaps are found at shutdown.
Canceling incoming migration helps, as it removes all unfinished (and
therefore busy) bitmaps.

Similarly on source we crash in bdrv_close_all which asserts that all
bdrv states are removed, because bdrv states involved into dirty bitmap
migration are referenced by it. So, we need to cancel outgoing
migration as well.

Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: default avatarAndrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Message-Id: <20200727194236.19551-17-vsementsov@virtuozzo.com>
Signed-off-by: default avatarEric Blake <eblake@redhat.com>
parent b91f33b8

migration/block-dirty-bitmap.c

+16 −0
Original line number Diff line number Diff line
@@ -657,6 +657,22 @@ static void cancel_incoming_locked(DBMLoadState *s) 
    s->bitmaps = NULL;

}



void dirty_bitmap_mig_cancel_outgoing(void)

{

    dirty_bitmap_do_save_cleanup(&dbm_state.save);

}



void dirty_bitmap_mig_cancel_incoming(void)

{

    DBMLoadState *s = &dbm_state.load;



    qemu_mutex_lock(&s->lock);



    cancel_incoming_locked(s);



    qemu_mutex_unlock(&s->lock);

}



static void dirty_bitmap_load_complete(QEMUFile *f, DBMLoadState *s)

{

    GSList *item;

migration/migration.c

+13 −0
Original line number Diff line number Diff line
@@ -188,6 +188,19 @@ void migration_shutdown(void) 
     */

    migrate_fd_cancel(current_migration);

    object_unref(OBJECT(current_migration));



    /*

     * Cancel outgoing migration of dirty bitmaps. It should

     * at least unref used block nodes.

     */

    dirty_bitmap_mig_cancel_outgoing();



    /*

     * Cancel incoming migration of dirty bitmaps. Dirty bitmaps

     * are non-critical data, and their loss never considered as

     * something serious.

     */

    dirty_bitmap_mig_cancel_incoming();

}



/* For outgoing */

migration/migration.h

+2 −0
Original line number Diff line number Diff line
@@ -335,6 +335,8 @@ void migrate_send_rp_recv_bitmap(MigrationIncomingState *mis, 
void migrate_send_rp_resume_ack(MigrationIncomingState *mis, uint32_t value);



void dirty_bitmap_mig_before_vm_start(void);

void dirty_bitmap_mig_cancel_outgoing(void);

void dirty_bitmap_mig_cancel_incoming(void);

void migrate_add_address(SocketAddress *address);



int foreach_not_ignored_block(RAMBlockIterFunc func, void *opaque);