Intel GDS/Downfall Linux Mitigation Updated To Confirm All Skylake CPUs Are Affected

[phoronix]

Phoronix: Intel GDS/Downfall Linux Mitigation Updated To Confirm All Skylake CPUs Are Affected

The Linux mitigation for the Intel Gather Data Sampling (GDS) "Downfall" vulnerability was updated to reflect all Skylake and Kabylake CPUs being vulnerable to this nasty issue. Due to those Skylake client processors reaching the end of their official support life at Intel, the original Linux mitigation for GDS/Downfall didn't properly protect those older Core processor models...

https://www.phoronix.com/news/Intel-Downfall-All-Skylake

[tildearrow]

Nooooooo! At this rate Skylake will perform equally as good as Pentium in 2030...

[stormcrow]

Nooooooo! At this rate Skylake will perform equally as good as Pentium in 2030...

A good reason to disable these mitigations if the likelihood of external access is slim to none. Keep in mind that if you're using a web browser on a client system that still counts as external access since you have no practical control or real insight into the external code each website loads and executes. Spectre and some of the rest of the hardware level vulnerabilities are remotely exploitable via web browser.

[pWe00Iri3e7Z9lHOX2Qx]

Nooooooo! At this rate Skylake will perform equally as good as Pentium in 2030...

I wonder how much faster than Skylake the prior gen Broadwell is at this point with all mitigations in place (outside of AVX-512). The IPC gains in Skylake were miniscule to begin with, less than 3%.

[edxposed]

I've heard that GDS/Downfall also affects libraries commonly used by browsers like Skia, so maybe Skylake's web performance will regress to the level of Android phones.

[gnattu]

I've heard that GDS/Downfall also affects libraries commonly used by browsers like Skia, so maybe Skylake's web performance will regress to the level of Android phones.

In fact, modern SoCs in Android phones already outperform Skylake in browser speed even without Downfall. We should realize that Skylake is an 8-year-old architecture after all.

[edxposed]

In fact, modern SoCs in Android phones already outperform Skylake in browser speed even without Downfall. We should realize that Skylake is an 8-year-old architecture after all.

In fact the desktop versions of Chrome and Firefox have more aggressive performance optimization strategies, while the mobile versions are biased towards saving size and memory, which sacrifices performance to some extent. Even with the state-of-the-art 8Gen2, Speedometer only reaches a little over 190.

[gnattu]

In fact the desktop versions of Chrome and Firefox have more aggressive performance optimization strategies, while the mobile versions are biased towards saving size and memory, which sacrifices performance to some extent. Even with the state-of-the-art 8Gen2, Speedometer only reaches a little over 190.

But 190 already outperforms most of the Skylake CPUs. Even the refreshed 7700K only scored ~120, and the laptop variants scored even lower. The software performance optimization is hard to overcome the old architecture.

[stormcrow]

But 190 already outperforms most of the Skylake CPUs. Even the refreshed 7700K only scored ~120, and the laptop variants scored even lower. The software performance optimization is hard to overcome the old architecture.

Benchmark scores for browsers are just bragging stakes once they have functional performance metrics. There's no practical difference in a website rendering and executing in 100 milliseconds or 200 milliseconds. Compatibility matters more. The only place where performance percentages matter in modern browsers are in testing phases, headless web crawlers, and that gawd awful pig of a platform Electron where they could speed things up by 300% and it would still seem to crawl like it was running on a 20 year old PC.

[onlyLinuxLuvUBack]

skylake with downfall, should it be renamed to skyfail or skyfall ?