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New Intel Vulnerability Affecting AVX2/AVX-512 with Big Performance Implications
- gymbeaux 3y agoBack when I had some old rack mount servers (Ivy Bridge Xeons) I would disable the mitigations where possible/not update microcode/BIOS. The attack vectors being somewhat niche and me being the only user means the trade off for performance wasn’t worth it. I think it’s a fallacy to assume known vulnerabilities MUST be patched… but alas if that’s not an option for whatever reason, I hope the plan is to move to AMD eventually. They have occasional vulnerabilities too, but so far nothing as detrimental to performance as Spectre or I assume Downfall.
- schemescape 3y agoMy understanding is that AMD processors also required mitigations for Spectre. Is that not the case? Or is the performance impact just different?
- gymbeaux 3y agoI might be mixing up Spectre and meltdown… one affected AMD but I don’t think the other did.
- schemescape 3y agoFor the record: Wikipedia seems to agree that Meltdown didn't affect AMD but Spectre did. I didn't realize that, so thanks!
- sillywalk 3y agoIt's called Downfall, and the page about is at https://downfall.page/ https://downfall.page/ " [Q] How long was this vulberability under embargo? [A] Almost one year. I reported this vulnerability to Intel August 24, 2022. " [Q] How practical are these attacks? [A] GDS is highly practical. It tooks me 2 weeks to develop an end-to-end attack stealing encryption keys from OpenSSL. It only requires the attacker and victim to share the same physical processor core, which frequently happens on modern-day computers, implementing preemptive multitasking and simultaneous multithreading.