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> The removal of Hyperthreading makes a lot of sense for Lunar Lake to both reduce the die size of the version of Lion Cove found in Lunar Lake along with simplifying the job of Thread Director.

And, you know, stop the security vulnerability bleeding.

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I don't think hyperthreading was the bulk of the attack surface. It definitely presented opportunities for processes to get out of bounds, but I think preemptive scheduling is the bulk of the issue. That genie not going back in the bottle another way to significantly improve processor performance for the same amount of instructions.

I think the real problem is cache sharing and hyperthreading kind of depends on it, so it was only ever secure to run two threads from the same security domain in the same core

Newbie question, if the cores share an L3 cache, does that factor in the branch prediction vulnerabilities? Or is the data affected by the vulnerability stay in caches closer to the individual core? I assume so otherwise all cores would be impacted but I’m unclear where it does sit

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