Linux 6.1 Adding Option To Disable Spectre-BHB On Arm Due To "Great Impact" On Performance

[fitzie]

do we really need this mitigation for normal user who only use youtube and steam and maybe some website

If your system runs untrusted code, then yes, there is a danger. This includes javascript, so it is possible that just visiting a website could expose your system. There is some work being put in to web browsers to address that exposure. That being said, I run with mitigations=off, which disables all of these workarounds. maybe I'll turn them on when I get a faster box.

[gosh000]

do we really need this mitigation for normal user who only use youtube and steam and maybe some website

it depends on attitude. For me 20% is nothing for better security. On the other hand cloud providers offer Arm servers as well.

[Aryma]

do we really need this mitigation for normal user who only use youtube and steam and maybe some website

[tunnelblick]

Does that affect M1, too? Especially considering the benchmarks we saw for the Asahi Linux project on this site?

[Michael]

Michael

Cortex?

Whoops, lol. yes. Thanks.

[leonmaxx]

Michael

from the likes of the Spectre-A15 through A78

Cortex?

[phoronix]

Phoronix: Linux 6.1 Adding Option To Disable Spectre-BHB On Arm Due To "Great Impact" On Performance

Disclosed back in March was the Spectre-BHB / Branch History Injection (BHI) speculative execution vulnerability that on the Arm side affected CPUs from the likes of the Spectre-A15 through A78 series as well as the likes of the X1, X2, and A710, plus the Neoverse E1 / N1 / N2 / V1 CPUs. Now for Linux 6.1, a command-line option is being added for ARM64 to be able to disable the Spectre-BHB mitigation due to the "great impact" to performance...

https://www.phoronix.com/news/Linux-6.1-Disable-ARM64-BHI-BHB