An interface redesign is much better. We can use git cherry-menu like this:

git icing -v3 upstreaming_branch master_branch | git cherry-menu upstreaming_branch

or redirect the stdin from the file:

git icing -v3 upstreaming_branch master_branch >porting_list; git cherry-menu upstreaming_branch <porting_list

The latter case also gives us the ability to modify the list for automatically blacklisting all the commits in it. We can add --auto-blacklist option. git cherry-menu can blacklist all the commits in porting_list automatically.