Arch Linux

ua4000

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Registered: 2015-10-14

Posts: 420

[SOLVED] Arch: Disabling Hyper-Threading ?

OpenBSD disables Hyper-Threading:
https://www.heise.de/security/meldung/S … 87035.html

Are there plans to follow this in Arch too ?

Thanks very much.

Edit:
topic from the link translated into English:
"To reduce the risk of Specter vulnerability attacks, the OpenBSD operating system now disables Multi-Threading on Intel processors."

Last edited by ua4000 (2018-06-23 07:40:01)

drcouzelis

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From: Connecticut, USA

Registered: 2009-11-09

Posts: 4,092

Website

Re: [SOLVED] Arch: Disabling Hyper-Threading ?

Slashdot article

I assume the usual general answer applies: Arch Linux will use the default configuration of the (mostly) unpatched software that is released by the official developers. In other words, if Linus decides to disable hyper-threading by default in Linux, then Arch Linux will too.

(I DO NOT REPRESENT ARCH LINUX IN ANY WAY.)

Last edited by drcouzelis (2018-06-20 17:50:07)

ooo

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Registered: 2013-04-10

Posts: 1,638

Re: [SOLVED] Arch: Disabling Hyper-Threading ?

Arch uses linux kernel (hence the name), not OpenBSD kernel, so this has nothing to do with Arch linux.

If linux kernel developers decided to disable SMT for everybody, that would be another story.

ua4000

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Registered: 2015-10-14

Posts: 420

Re: [SOLVED] Arch: Disabling Hyper-Threading ?

Thanks for the insight!

progandy

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Registered: 2012-05-17

Posts: 5,199

Re: [SOLVED] Arch: Disabling Hyper-Threading ?

If you want to disable smt on your own machines, then you can use the kernel paramater nosmt.
https://www.kernel.org/doc/html/v4.17/a … eters.html

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ua4000

Member

Registered: 2015-10-14

Posts: 420

Re: [SOLVED] Arch: Disabling Hyper-Threading ?

Thanks for the very useful link - I bookmarked it :-)

For now I disabled Hyper-Threading in BIOS to test what the "feeled" system degradation could be.

loqs

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Registered: 2014-03-06

Posts: 17,377

Re: [SOLVED] Arch: Disabling Hyper-Threading ?

OpenBSD are proven correct in predicting more variants https://git.kernel.org/pub/scm/linux/ke … 9c1e17aa2d