AMD News Archives
Linux 5.13 Will Stop Restricting CPU Power Metrics Access For AMD Energy Driver

Following the PLATYPUS discovery last year that CPU energy information could be used for possible side channel attacks, the Intel RAPL counters were not only restricted to root but the "amd_energy" driver for exposing CPU energy information on supported Zen series CPUs was also dialed back to root-only in the name of security. Linux 5.13 is introducing a new mechanism so AMD CPUs will be able to still read the energy counters even if not operating as root.

11 April 2021 - Let Anyone Read It... - 9 Comments
AMD Sends Out Linux Kernel Patches To Allow Disabling Predictive Store Forwarding (PSF)

AMD last week published a security whitepaper on Zen 3's Predictive Store Forwarding (PSF) functionality introduced with Ryzen 5000 series and EPYC 7003 series processors. In the whitepaper they mentioned Linux patches were published for allowing this feature to be disabled if concerned about the security risk, well, today those patches were made public.

6 April 2021 - PSF Mitigation - 1 Comment
AMD Zen 3 Tuning Backported To The GCC 10 Compiler

In the past few weeks since the introduction of the EPYC 7003 "Milan" processors there has finally been AMD Zen 3 "Znver3" tuning work that's been hurried into the GCC 11 compiler code-base ahead of its stable release in the coming weeks. That initial Zen 3 tuning work has also now been back-ported to the GCC 10 branch ahead of its next point release.

1 April 2021 - Znver3 + GCC 10 - 7 Comments
The Most Popular AMD Linux/Open-Source News For Q1'2021

With AMD's busy Q1 of introducing the Radeon RX 6700 XT graphics card, introducing the Ryzen 5000 mobile series, the AMD EPYC 7003 "Milan" series launch, and continuing to advance their open-source/Linux software efforts, it was another busy quarter. Here is a look back from the Linux/open-source perspective of what interested readers the most.

31 March 2021 - AMD Linux - Add A Comment
New AMD Zen 3 Fixes Published For The GCC 11 Compiler

Last week there were a few round of Zen 3 compiler patches published and quickly merged into the GCC 11 compiler code-base ahead of its imminent release, This week there is some new activity albeit fixes for this new "Znver3" target.

25 March 2021 - Znver3 Fixes - 17 Comments
AMD Sends Out New Linux Code For SEV-SNP With EPYC 7003 Series

In addition to AMD EPYC 7003 "Milan" processors offering fantastic performance, another important highlight for these new Zen 3 server processors is SEV-SNP for upping the Secure Encrypted Virtualization capabilities. AMD has been offering SEV "Secure Nested Paging" patches via a GitHub repository while now they are working towards mainlining this feature for the Linux kernel.

24 March 2021 - AMD SEV-SNP - 1 Comment
AES-NI XTS Crypto Performance Looking Good For AMD With Linux 5.12 Fix

Of the performance-related changes with Linux 5.12 worth noting is faster AES-NI XTS performance for systems relying upon return trampolines "Retpolines" as part of the CPU's Spectre V2 mitigations. On the Intel side this primarily impacts older CPUs where Retpolines is still used while on the AMD side through Zen 3 the Retpolines is still relied upon, which as shown by these benchmarks is now much better off for AMD Ryzen AES XTS performance as measured by Cryptsetup.

1 March 2021 - AES-NI XTS - 5 Comments
The State Of ROCm For HPC In Early 2021 With CUDA Porting Via HIP, Rewriting With OpenMP

Earlier this month at the virtual FOSDEM 2021 conference was an interesting presentation on how European developers are preparing for AMD-powered supercomputers and beginning to figure out the best approaches for converting existing NVIDIA CUDA GPU code to run on Radeon GPUs as well as whether writing new GPU-focused code with OpenMP device offload is worthwhile.

21 February 2021 - LUMI Supercomputer - 115 Comments
AMD Is Currently Hiring More Linux Engineers

It looks like thanks to AMD's increasing sales and continuing successes in the enterprise space with more HPC wins and the like, AMD is hiring more Linux engineers. AMD currently has several interesting job openings on the Linux front.

11 February 2021 - More Linux! - 96 Comments
The Latest Open-Source AMD Firmware / Coreboot Happenings In Early 2021

While AMD has been crushing it when it comes to Linux performance and generally delivering good launch-day support, the one area many Linux/open-source advocates have been eager and hopeful to see change is around Coreboot support and ideally open-source firmware support such as by re-opening AGESA. Both inside and outside of AMD there continues being work in this direction.

7 February 2021 - Open-Source AMD Firmware - 26 Comments
AMD Regression On Linux 5.11 Being Addressed By New CPUFreq Patches

The AMD "frequency invariance" saga with Linux 5.11 continues... While there was a patch to address the previously noted performance regression caused by the introduction of frequency invariance and seen when using the Schedutil governor, a new CPUFreq-side patch series has been proposed instead -- both of which are addressing the performance issue with this new kernel for AMD Zen 2 / Zen 3 systems.

4 February 2021 - Linux 5.11 - 3 Comments
A Fix Has Been Proposed For The Slower AMD Performance On Linux 5.11

With the in-development Linux 5.11 kernel there are many great features and improvements especially for AMD users with some new drivers and other pleasant enhancements. But as I outlined back on Christmas day: Linux 5.11 Is Regressing Hard For AMD Performance With Schedutil. Fortunately, a fix is now en route to the Linux 5.11 kernel for fixing that performance regression affecting AMD Zen 2/3 desktops and servers.

21 January 2021 - Frequency Invariance Indeed - 6 Comments
AMD Wowed Linux Users In 2020 With Their Fantastic Zen 3 CPUs, Timely New Open-Source GPU Support

AMD this year not only delivered the very powerful Ryzen 5000 "Zen 3" desktop processors and initial Radeon RX 6000 "Big Navi" graphics cards but for exciting Linux users was the timely open-source support for the new GPUs well in advance (and also already preparing for some 2021 graphics products) as well as more timely support around Zen 3 thermal support and other additions. AMD's open-source timing is still improving although not yet optimal but all in it was a hell of a year for AMD Linux users.

29 December 2020 - 2020 AMD Highlights - 28 Comments
Linux 5.11 Is Looking Like A Wild And Bumpy Ride On AMD CPUs So Far

A few days ago I noted nice AMD EPYC performance improvements with PostgreSQL when running on Linux 5.11 compared to prior kernels. I've confirmed that for even more AMD EPYC servers now that the PostgreSQL uplift is there, but other workloads are unfortunately regressing for both Ryzen and EPYC. Here's the start of an exciting Christmas benchmarking adventure looking at this change with Linux 5.11...

24 December 2020 - PostgreSQL - 5 Comments
AMD SB-TSI Sensor Driver Set To Appear With Linux 5.11

There are a lot of changes coming with Linux 5.11 and on the AMD side includes the likes of VanGogh and Dimgrey Cavefish graphics support, AMD EPYC Zen 3 support in the AMD_Energy driver, AMD RAPL Zen1/Zen2/Zen3 PowerCap support, an AMD SoC PMC driver, and the AMD Sensor Fusion Hub driver for Ryzen laptops is finally being mainlined... Another new addition was queued up this weekend by way of hwmon-next and that's the AMD SB-TSI sensor driver.

13 December 2020 - AMD SB-TSI - 2 Comments
Mesa 21.0 Begins Landing Optimizations For AMD Smart Access Memory

While AMD Smart Access Memory has already been supported under Linux for some time with its resizable BAR functionality, only now with all the excitement around the feature being promoted with the Ryzen 5000 series and Radeon RX 6000 series hardware is the Mesa driver code beginning to see some optimizations for it.

9 December 2020 - Mesa 21.0 - 10 Comments

1217 AMD news articles published on Phoronix.