Linus Torvalds, the creator of Linux, responded to a recent patch for the Micro Architecture X86_64 with supporting compiler keys by expressing his criticism. The patch introduced a new version system for the Microarchitecture LEVEL, as reported by AMD, Intel, Red Hat, and SUSE.
The new version system includes extensions such as AVX2, BMI2, FMA, LZCNT, MOVBE, and SXSAVE for X86-64-V3, and AVX512F, AVX512BW, AVX512CD, AVX512DQ, AVX512VL for X86-64-V4. However, Linus Torvalds raised three main points of criticism towards this new system.
- Linus pointed out that the classification of versions is unofficial and lacks formal correspondence.
- He argued that the new version system complicates the understanding of processor capabilities by replacing a simple question with a more complex one.
- Linus criticized the attempt to simplify CPUID by linearizing it into versions, highlighting the anomaly where newer processors without AVX-512 support are classified as younger versions compared to older processors with AVX-512 support.
/Reports, release notes, official announcements.