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Massive CPU design flaw

Posted: Thu Jan 04, 2018 4:35 pm
by Tunnelcat
These are a couple of serious vulnerabilities that affect ALL Intel and AMD CPU chips that have been produced since 1995, practically every computer and device running today. They're called Spectre and Meltdown. I saw that Microsoft just released an off axis patch for it today, although it was originally supposed to be released on Jan. 9, 2018, but because of the early news leak, they dumped it on everyone today. Since I've got an older Intel CPU, I'm wary of installing this patch because it may noticeably slow down the CPU. Anybody install this patch yet on their systems and notice any difference in performance?

https://www.howtogeek.com/338269/a-huge ... r-pc-soon/

Re: Massive CPU design flaw

Posted: Thu Jan 04, 2018 5:41 pm
by Krom
Stuff that ran at 144 FPS before the update, still runs at 144 FPS after the update.

Some storage benchmarks show a fairly consistent hit to performance in random 4KB reads, but most games seem to not care at all (the majority of them actually score almost 1% faster after the patch even).

Re: Massive CPU design flaw

Posted: Thu Jan 04, 2018 5:57 pm
by Tunnelcat
Krom wrote: Thu Jan 04, 2018 5:41 pm Stuff that ran at 144 FPS before the update, still runs at 144 FPS after the update.
Yeah, but you've got a newer Ferrari of a system. Mine, it's closer to 7 a year old Chevy. :wink:

Re: Massive CPU design flaw

Posted: Fri Jan 05, 2018 12:00 pm
by Tunnelcat
Is there a way to test the speed of my system's CPU before I update things? How about the storage benchmark? There have been many warnings that this patch can impact a CPU's performance by up to 30%.

Edit: Nevermind Krom. I went ahead and ran the patch. I also found out that Intel is also going to have firmware updates for about 90% of their processors pushed out for download on January 12, by next week.

https://www.pcworld.com/article/3245606 ... c-mac.html

Re: Massive CPU design flaw

Posted: Fri Jan 05, 2018 4:13 pm
by Krom

Re: Massive CPU design flaw

Posted: Sat Jan 06, 2018 1:43 am
by AlexanderBorisov
I don't care. The vulnerability means that a program can get a kind of read access to kernel memory (in it's own address space). I don't see how it can harm me. As a person interested in sytem programming some time ago I found about another vulnerability like this, also concerned with memory caching, by using it you could gain read AND WRITE access to SMBIOS (used for hardware maintenance events like thermal monitoring), that is supposed to be unaccessible even to OS! Even checked that it actually worked, imaging an SMBIOS virus completely invisible to anything! But at least you need a driver on Win7-64 to exploit this. And there is Row Hammer attack on memory that can theoretically give you write access to physical memory, too... BTW on XP system and Win7-32 the whole physical memory could be open as a file (read/write access) under admin privileges, hopefully they limited it to reading BIOS data tables in Win7-x64. And no one cared that time!

Re: Massive CPU design flaw

Posted: Sat Jan 06, 2018 8:05 am
by Krom

Re: Massive CPU design flaw

Posted: Sat Jan 06, 2018 3:37 pm
by Tunnelcat
Thanks for that. So far, I haven't noticed much of a difference on my gaming system with just playing games. But my far older Intel Duo Core HP Touchsmart Win 7 machine that can't even be upgraded to Win 10, it's quite noticeable of an impact. It was already a slug to begin with, so it's about to be retired anyway, once I rip and digitize all my music.