How much are you willing to sacrifice to make sure your computer is secure? Most computer users who are willing to secure their systems know that they have to do something in return. The trade-off is usually reduced usability, additional costs for products (like antivirus), or reduced system performance. However, many Linux users were not prepared for the Spectre V2 patch, which reduced the performance of Intel processors by up to 50%.
This patch was released with the Linux 4.20. This patch no longer allows attacks using the Spectre v2 vulnerability, but it does dramatically reduce the performance of systems using Intel processors with Hyper-Threading enabled. To achieve this reduction, processors must be running the latest microcode update, and the speed reduction can be up to 50%.
Before the release of Linux kernel 4.20, there was no update about this tragic decrease in system performance. When systems are running "heavy" processes and their system is only performing at 50% of its real power, users start to wonder if this move was worth it, and if it is really worth sacrificing half the power of their processor to make their system more secure. Finally, as Arjan van de Ven also mentions , Intel should have STIBP (Single Thread Indirect Branch Predictor) disabled by default, just like AMD does.
