Personal computing discussed

Moderators: Flying Fox, morphine

Maximum Gerbil
Topic Author
Posts: 4471
Joined: Tue Aug 10, 2004 10:10 am
Location: Ottawa, Canada

Intel Speculative Execution - yet another flaw

Thu Jun 14, 2018 12:01 pm

Lazy FP state restore leaks state, including potentially your crypto keys: ... 00145.html

So far Intel only, not AMD.

Guess I need to wait a bit longer to build a new PC: ... 01#1080001
Gerbil Team Leader
Posts: 239
Joined: Tue Apr 25, 2006 7:57 am
Location: Madison, WI

Re: Intel Speculative Execution - yet another flaw

Thu Jun 14, 2018 12:47 pm

Compared to Meltdown and Spectre, this one is a non-issue, as most modern OSs (Windows and Linux 4.9 and later) already use Eager FP state save/restore anyway. I wouldn't let this one hold off a purchase.

Lazy FP save/restore comes from an age of separate Math Co-processor chips where most of the overhead was simply transferring data between the CPU, FPU and RAM. Especially since XSAVEOPT which does optimizations in hardware, Eager FP is now the norm from what I understand.
Intel Core i7 4790K, Z97, 16GB RAM, 128GB m4 SSD, 480GB M500 SSD, 500GB WD Vel, Intel HD4600, Corsair HX650, Fedora x64.
Thinkpad T460p, Intel Core i5 6440HQ, 8GB RAM, 512GB SSD, Intel HD 530 IGP, Fedora x64, Win 10 x64.

Who is online

Users browsing this forum: No registered users and 1 guest