[tomek@vz]

Updates

The upcoming Linux 6.15 kernel is set to finally introduce a standardized way of informing user-space of GPUs becoming hung or otherwise unresponsive. This is initially wired up for AMD and Intel graphics drivers on Linux so the user can be properly notified of problems and/or user-space software taking steps to address the hung/unresponsive graphics processor.

On top of all the recent x86/x86_64 Linux kernel crypto improvements made recently by Google engineer Eric Biggers to better laverage AVX-512 and other modern x86 ISA features, a new patch-set posted today by Biggers would help make all x86/x86_64 kernel encryption/decryption at least slightly faster.
The new patch series isn't about making use of some new CPU ISA features or anything wild like that but rather just cleaning up some existing code so that the x86 kernel-mode FPU always works reliably with soft IRQs so that some old SIMD helper crypto fallback code can be removed. That fallback code was "really bad for performance" and presented performance implications for those not even needing to rely on it.

SK has been working on a Linux kernel feature dubbed Lazy Unmap Flush "LUF" to defer TLB flushes until folios have been unmapped and freed are eventually allocated again.
This Lazy Unmap Flush work began after encountering a lot of migration overhead around TLB shootdowns on servers with tiered memory making use of CXL memory.
The end result is what is most interesting and important: the LUF patches yielded TLB shootdown interrupts being reduced by around 97%. Furthermore, the test program runtime of using Llama.cpp with a large language model (LLM) yielded around 4.5% lower runtime.