I didn't mean to imply Apple (and Google) hadn't been spearheading multi-year efforts to ship this in collaboration with Arm, I regret a little that it came across that way. Just that it would be nice to see production use of it acknowledged even just as a passing comment.

As an outsider I am quite ignorant to what security developments these companies are considering and when the trade-offs are perhaps too compromising for them to make it to production. So I can't appreciate the scale of what Apple had to do to reach this stage, whereas with GrapheneOS I know they favour privacy/security on balance. I use that as a weak signal to gauge how committed Apple/Google/Microsoft are to realising those kinds of goals too.

ARM largely built and shipped it on their own. Cortex cores were the first real world implementation. Pushing ARM to care about it as a security feature instead of only a bug finding feature is something Apple and Google are probably responsible for doing. Pixels are not the only Android devices making MTE but were the first to take advantage of the CPU support by actually setting it up and making it available for use. There are other Android devices doing that now too.

Qualcomm has to make their own implementation which has significantly delayed widespread availability. Exynos and MediaTek have it though.

Personally I had no idea anyone had shipped this. I knew that MTE existed, though I don’t think I knew about EMTE.

Nice to hear it’s already in use in some forms.

And of course it seems pretty obvious that if this is in the new iPhones it’s going to be in the M5 or M6 chips.