Nah, it was more than that: The patches do things like add the garbage MSR writes to the kernel entry/exit points. That's insane. That says "we're trying to protect the kernel". We already have retpoline there, with less overhead.

That was about patches to the linux kernel, not the microcode patches.

Yes, but as far as I know Linus has made no comment on the microcode patches, so mm-vorticesoft is probably referring to the Spectre patches in general.

The microcode patches are binary blobs against a proprietary and secret ISA, how can anyone comment on their quality?

When I read it I believed that Linus was implying that the suggested mitigation was so insane that it seemed like Intel MIGHT be hiding how broken they believed their hardware was with such over-the-top reactions. As well as indirectly asking if they believed the currently accepted mitigation method (retpoline) was considered ineffective.

His overall point was a bewilderment at the incompetent and non-sensical patches that were being given as "fixes" in this issue. Linus was pointing out a particular instance of that, but this news and other behaviour from Intel seems to indicate this is part of an endemic, cultural, administrative issue inside the company.