Not really sure if he "supports" it but neither does he go against it.
Basically he's saying that Windows security WILL be hackable and will be
renedered useless.
“The real problem, I feel, is that clever hackers will bypass the whole key
issue either by getting a key of their own (how many of those private keys
have stayed really private again? Oh, that’s right, pretty much none of
them) or they’ll just take advantage of security bugs in signed software to
bypass it without a key at all.”
But I guess that's expected from Mr. Torvalds.