DBCC checkDB stuck in killed/rollback state
Restarting a server while something is rolling back, is almost always a bad idea. You may make things worse. 

You don't say if you are using one of the repair options with DBCC CHECKDB if you are, it can complicate things even more.

It has been a few hours since the original question was posted, so things have probably either self corrected or gotten worse.  Hopefully you have backups, that you will be able to use in the recovery, if things are not going well.

Some Related posts that may help


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