4 ms·
No details on the performance impact of the microcode update. Presumably it disables speculative execution of vzeroupper?
by ComputerGuru 3y ago
No details on the performance impact of the microcode update. Presumably it disables speculative execution of vzeroupper?
- hinkley 3y agoOr adds a guard. They mention perf issues for the workaround but they're notably absent from the microcode commentary. I wonder what this is going to do to the new AMD hardware AWS is trying to roll out, which is supposed to be a substantial performance bump over the previous generation.
- infinityio 3y agoIt looks like this is a Zen 2-only exploit, so it shouldn't have any impact - AWS are likely already running hardware that isn't vulnerable to this
- hinkley 3y agoThe way Spectre and Meltdown played out, you'll have to excuse me if I stand outside the blast radius while we figure out if there's a chapter 2, 3 or 4 to this story. They've proven Zen 2 has this problem. They haven't proven no other AMD processors have it. A bunch of people looking to make names for themselves are probably busily testing every other AMD processor for a similar exploit.
- heywhatupboys 3y ago> The way Spectre and Meltdown played out, you'll have to excuse me if I stand outside the blast radius while we figure out if there's a chapter 2, 3 or 4 to this story. I am OOTL on this one, do you have some information you could share?
- loeg 3y agoThere has been a long trickle of similar bugs to Spectre/Meltdown coming out long after the initial bugs and "fixes" were published. (The early fixes were all, in some sense, incomplete.)
- kzrdude 3y agoThere was a list of vulnerabilities in this comment up top: https://news.ycombinator.com/item?id=36849914 https://news.ycombinator.com/item?id=36849914
- Dunedan 3y agoAWS does offer Zen 2 based EC2 instances though (C5a family for example).
- jeffffff 3y agoshouldn't have any effect, the new amd hardware is zen 4 and this only affects zen 2