Intel Gen7 GPU performs significantly worse on Linux after security patch

Seventh-generation Intel GPUs, which are in Ivy Bridge and Haswell processors, perform much worse than before after a security patch for the Linux kernel has been implemented. With the Core i7-4790K, the GPU performance dropped by an average of 42 percent.

Earlier this week, patches for Intel’s graphics drivers for Linux were revealed due to a vulnerability labeled CVE-2019-14615. Phoronix wrote about it. According to that site, the security problem was affecting Intel’s Gen9 and Gen7/7.5 GPUs. Gen8 was unaffected by the implementation of previous code that fixed the issue on that generation. The vulnerability makes it possible to retrieve information from a system, but exploiting the vulnerability requires local access to the system, which makes the impact relatively limited.

The impact on performance is significant, Phoronix shows. The influence on the Gen9 GPU turned out to be minimal, but the site publishes extensive benchmarks of a Core i7-3770K and a Core i7-4790K . This shows that the GPU of the 3770K is on average 18 percent worse and that of the 4790K 42 percent worse. Phoronix doesn’t consider improvement with new drivers likely because Intel has been working on it for months and rollback due to the “mitigations=off” kernel parameter is not possible.

Many details about vulnerability CVE-2019-14615 are unknown at the time of writing. Intel itself considers the impact “medium” and the company reports that multiple Core, Xeon, Pentium, Celeron and Atom generations have been affected. Intel also advises Windows users to update Intel graphics drivers. It is not known whether and, if so, to what extent these also result in a reduction in performance.

The patch was one of several Intel released Tuesday, including for a leak in the VTune Profiler. Threatpost lists the patches.

Source: Phoronix