>Why should I disable hyperthreading? tl;dr: it's vulnerable to spectre. The two virtual threads on the physical core share the physical L1-Cache and the Translation Lookaside Buffer. Those are exposed to timing attacks. You simply dont want privileged and unprivileged processes to share a cache or a buffer. You can prevent this by disabling hyper-threading. >Source? tomshardware.com/news/openbsd-disables-intel-hyper-threading-spectre,37332.html theregister.co.uk/2018/06/20/openbsd_disables_intels_hyperthreading/ You need a more credible source? Go search your own, they are out there. >A bunch of kiss-less openBSD developers are exaggerating, why should I care? Because there are currently 5(formerly 6) new spectre vulnerabilitys under embargo. The OpenBSD guys leaked one of the six vulnerabilitys: Lazy FP State Restore (CVE-2018-3665). It's safe to assume that they know more about this shit than you and I. Also they worked on a spectre/meltdown fix 11 (ELEVEN!) years ago. Source: marc.info/?l=openbsd-misc&m=118296441702631&w=2 >Will it impact performance? Hyper-threading can even lower performance. But it really depends on the type of your workload. You can enable/disable hyperthreading on the fly in Linux (e.g. before/after compiling stuff, rendering, calculate your weight). >on the fly? How? Find out which virtual cores share the same physical core (core_id) grep /proc/cpuinfo -e processor -e core\ id
Write a script like enable_ht and disabled_ht and store it somewhere like /usr/local/bin. Make sure this folder is in your $PATH disable_ht: #!/bin/bash echo 0 > /sys/devices/system/cpu/cpu1/online echo 0 > /sys/devices/system/cpu/cpu3/online echo 0 > /sys/devices/system/cpu/cpu5/online echo 0 > /sys/devices/system/cpu/cpu7/online echo "Hyperthreading disabled"
echo 1 > is for enabling. >What about other OS? Dunno, disable it in BIOS or use a search engine.
>under embargo can you explain further? how come embargos are possible on things like this?
Lincoln Rogers
>how come embargos are possible on things like this? you dont sue
Hunter Rodriguez
>tfw bought a 6700k a year and a half before ryzen came out I'm sorry, Jow Forums, I should have believed you and JustWaited™. The one time in my life I purchase an Intel CPU and my shit gets thoroughly fucked up. I miss my Phenom II every day...
Liam Turner
microsoft needs more time for fixing the stuff, so everyone else waits for them with releasing information and bugfixes
Lmao how Intel can go from dominating the market to JUST status is baffling to me.
Jonathan Richardson
Will this effect my fps in games ? I reverted all spectre/meltdown patches for more performance.
Ian Cox
>there are people who actually fell for the hyperthreading meme fucking jej
Isaiah Miller
boku no pico
Brody Anderson
The emperor had no clothes. The whole "muh IPC" was based on shitty hacks and shortcuts.
Dominic Fisher
>muh IPC That's pretty much the only excuse for hating pic related, referring to single core benchmarks in 640x480 from fucking 2003, any modern software or game will leverage this fine.
If it's so easy to turn hyperthreading on or off, couldn't a virus taking advantage of it just turn it on first ?
Landon Ortiz
only with escalated privileges
Aiden Martinez
probably less so if from the bios level my ryzen bios has options for smt and xfr
Cooper Jenkins
You give the hardware and software vendors a chance to fix or mitigate the issue first, so the exploit isn't out in the open for jamal to use before it's been patched. Because the hardware and software vendors know that the exploit WILL be released to the public, they have incentive to actually fix that shit.
If you just drop it (a zero day), then there's a period where everyone is vulnerable and not patched, and if you only tell the vendors, then they don't really have any incentive to fix it. The embargo gives vendors time to fix the issue while also lighting a fire under their ass to make sure they do so.
Jack Flores
in theory. in reality the vendors keep asking for extension after extension, so everybody's stuck on vulnerable code for months longer than necessary.
Leo Taylor
Having the required privileges would make this side-channel irrelevant anyway, you could just directly view the process memory.
Austin Sullivan
Ya know what would REALLY light a fire under their ass? releasing the damn exploit immediately
Colton Wilson
And leave everyone vulnerable in the meantime?
Luis Wood
Basically if you're still running intel, you don't give a fuck about security anyway so what difference does it make?
Joseph Parker
prisma Illya
Charles Thompson
There are no spectre or meltshit viruses period. AMD propaganda made people lose performance
Ian Johnson
Is FreeBSD under embargo or cuckBSD got ignored on this one?
Jonathan Miller
Who cares about freeBSD.
OpenBSD is where it's at.
Liam Stewart
I do, for 3-6 months before we migrate away from FreeBSD at work.
I've got a Cyrix processor within reach and multiple PowerPC machines in the toom
Alexander Anderson
my negro
Tyler Gonzalez
eh not very they are only after big datacenters shit not retards from Jow Forums fucking POST them i have been dying to see some in the wild, never saw them back in the day cunt.
Michael Thompson
No camera
Camden Robinson
Jow Forumsood
James Rodriguez
This, it's quite incredible how people will believe it's impossible for other researchers and black hats to find out this vulnerabilities Theo just proved for terribly bad the embargoes work, they are just another form of corporate welfare to keep the major vendors ahead of the minor ones
Jack Ross
Literally a non-issue for me.
John Baker
RRAAAHHHHH IT'S NOT FAIR I FUCKING HATE AMD AND THEIR ARMY OF HACKERS
Owen Miller
don't really care enough to turn off the hyperthreading, but hopefully there's a settlement soon with all of these performance-degrading vulnerabilities desu
Benjamin Morgan
We don't know but apparently part of them were under the embargo for FP Lazy Restore, so most probably they are for this ones Their fix was rushed though, so I guess you can expect them to not have the patches ready Most timing vulnerabilities are pretty much irrelevant for desktops, as long as you aren't running untrusted code on your machine you shouldn't care about side channel attacks However cloud vendors do care, and a lot
Jackson Hernandez
It's all crashing down. How did jewtel go from undisputed King of shit mountain to JUST in such a short time period?
Carter Sullivan
and you can thank intel for that i bet they still haven't paid a dime
Brody Kelly
>The whole "muh IPC" was based on shitty hacks and shortcuts SHUT IT DOWN
Chase Perry
yep fuck intel i literally got rid of my i5 4690 when zen dropped competition and talent on both sides. they let their once decent IGP die, then they got lazy and let all the good people walk away.
Xavier Brooks
>buy an unlocked i7 >D-don't overclock, goyim! It's bad for the cpu! >T-turn off HT, it's not secure! Now you are stuck with your lock i5 on your zx70 board and you paid 3 times as much as you needed. Lol
Noah Long
most people wont care about any of it tho.
The people that do care are ditching intel ( big server farms, embedded markets etc)
Lincoln Carter
tl;dr does this affect my windows?
Evan Reed
This is p3 bug
Jose Bennett
>The people that do care are ditching intel ( big server farms, embedded markets etc) This is what matters the most though. Your average normalshit is irrelevant.
Nolan Reed
What are the chances that this become a serious issue and intel drops a forced patch on every cpu to forcibly turn off ht?
Aiden Rogers
funny thing is though intel lost those markets years ago but everyone was waiting for zen.
Now Gen 2 and 7nm has already dropped intel are fucked! Yes. Well basically i reckon they are fucked, considering most servers are nix based hahahahah
Benjamin Hughes
this is just a shitty meme. they want that people install updates and change settings so the computer becomes slow and retards would buy new. no one has ever hacked anything with these and it was supposed to be so easy that you could do it with js through a web browser..
