AMD News Archives


1,663 AMD open-source and Linux related news articles on Phoronix since 2006.

Linux 5.16 To Expose AMD PSF Disable Bit To KVM Guests

While the Linux kernel still hasn't added any formal control yet for AMD Predictive Store Forwarding to disable it short of also toggling Spectre V4 / SSBD, with the Linux 5.16 kernel the AMD PSF bit will now be exposed to KVM guest virtual machines so that they -- either with a patched/future kernel or for other operating systems -- may choose to toggle explicitly disable this AMD CPU feature.

28 September 2021 - Predictive Store Forwarding - Add A Comment
Updated AMD P-State Driver Published For Linux

Earlier this month AMD published their "amd-pstate" Linux driver that leverages ACPI CPPC data to make more informed CPU frequency scaling decisions with an aim to boost the performance-per-Watt for Zen 3 (and eventually Zen 2) processors on Linux. The second spin of that "amd-pstate" Linux kernel driver is now available for testing.

26 September 2021 - AMD P-State - 5 Comments
AMD + Valve Focusing On P-State / CPPC Driver With Schedutil For Better Linux Efficiency
AMD + Valve Focusing On P-State / CPPC Driver With Schedutil For Better Linux Efficiency

As reported at the start of August, AMD and Valve have been working on Linux CPU performance/frequency scaling improvements with the Steam Deck being one of the leading motivators. As speculated at that time, their work would likely revolve around use of ACPI CPPC found with Zen 2 CPUs and newer. Published last week was that AMD P-State driver for Linux systems indeed now leveraging CPPC information. AMD formally presented this new driver yesterday at XDC2021.

18 September 2021 - AMD P-State - 28 Comments
Still-Pending AMD PSF Control Patch To Be Retailored For KVM

Of all the great stuff for AMD in Linux 5.15, one of the patches still not having yet been mainlined is the control support around Predictive Store Forwarding (PSF) with Zen 3 processors. It's been six months since AMD published their security whitepaper around PSF while the Linux patch has yet to be mainlined while now it seems will be updated for a reduced focus on KVM usage.

13 September 2021 - Predictive Store Forwarding - Add A Comment
Linux 5.15 Is A Very Exciting Kernel For AMD
Linux 5.15 Is A Very Exciting Kernel For AMD

While working on my usual Linux kernel feature overview that summarizes the many articles over the past two weeks outlining all of the new features and changes merged, one area that particularly stands out for Linux 5.15 are all of AMD's upstream contributions that happened to make it in this kernel. There is a lot of new enablement on the AMD side -- both for CPUs and Radeon graphics -- but also improving existing hardware support.

12 September 2021 - Lots Of AMD Enablement - 40 Comments
AMD PTDMA Driver Landing For Linux 5.15 After Two Years In The Works

Going back to September 2019 was work on the AMD PTDMA driver for supporting this controller found on modern AMD processors for high bandwidth memory-to-memory and I/O copy operations. With the Linux 5.15 cycle the AMD PTDMA driver is finally being merged to the mainline kernel.

9 September 2021 - Pass Through DMA - 4 Comments
AMD Has An Important Suspend/Resume Fix With Linux 5.15

Since last year AMD has been working to get its s2idle / suspend-to-idle S0ix sleep state code in order for supporting this lowest power platform idle state on newer AMD laptops and there has also been other AMD suspend/resume improvements in recent times. Now with the Linux 5.15 kernel cycle is an important fix for the AMD s2idle code.

8 September 2021 - Fixing - 24 Comments
AMD SB-RMI Driver Coming For Linux 5.15

AMD continues pushing new code out for Linux in better exposing their platform's capabilities in the open-source world. The latest AMD driver work now queued via "-next" branches for introduction this autumn in Linux 5.15 is SB-RMI sensor support.

2 August 2021 - AMD SB-RMI - 12 Comments
AMD VanGogh APUs Get New Audio Driver For Linux

Since last year AMD has been working on VanGogh APU support for Linux initially with their graphics driver support and that has spread to other areas. It also turns out now that with VanGogh APUs will be a new Linux audio driver.

9 July 2021 - VanGogh Sound - 7 Comments
Linux Formerly Affected By A KVM SVM Guest-To-Host Breakout Code Vulnerability

Linux's KVM virtualization component previously could allow a virtual machine guest relying on AMD SVM virtualization to breakout into the host. This bug persisted in the Linux kernel from late 2020 to March 2021 before being addressed and is the first known issue of such a guest-to-host breakout that didn't also depend upon bugs within user-space components.

29 June 2021 - EPYC Breakout - 2 Comments
AMD PSF Control Support Still Awaiting The Mainline Linux Kernel

It's been three months since AMD published a security whitepaper outlining the possibility of a side channel attack with PSF. The Predictive Store Forwarding functionality is new to AMD Zen 3 (Ryzen 5000 / EPYC 7003 series) processors and as part of their security analysis they are allowing users the ability to opt-out of using this feature in the name of greater security but the feature still hasn't been picked up for the mainline Linux kernel.

23 June 2021 - Predictive Store Forwarding - 3 Comments
AMD SEV/SEV-ES Local Migration Support Patches For Linux
AMD SEV/SEV-ES Local Migration Support Patches For Linux

Google engineers have prepared a set of Linux kernel patches allowing for AMD Secure Encrypted Virtualization (SEV) / SEV-ES encrypted state to allow for local migration support of these encrypted virtual machines on the same host.

21 June 2021 - AMD SEV Local Migration - 1 Comment
AMD Continues Working To Mainline Their PTDMA Driver For Linux
AMD Continues Working To Mainline Their PTDMA Driver For Linux

Published all the way back in September 2019 was a Linux driver for supporting the Pass-Through DMA controller for EPYC processors. The PTDMA hardware allows for high bandwidth memory-to-memory and I/O copy operations. Now mid-way through 2021 that AMD PTDMA Linux driver remains in the works and is up to its tenth driver revision while waiting to see if it's now ready for mainline or further changes are still deemed necessary.

20 June 2021 - PTMA Driver v10 - Add A Comment
OnLogic Introduces New AMD Ryzen Powered Industrial Grade Mini-ITX Thin Client
OnLogic Introduces New AMD Ryzen Powered Industrial Grade Mini-ITX Thin Client

Often times when checking out thin clients and industrial PCs / IoT units from OnLogic and other industrial PC vendors, they tend to be Intel powered and within the forums the first question is often about any AMD equivalent... For those wondering about any new AMD-powered thin clients / mini-ITX systems within an aluminum chassis, OnLogic has introduced the TM800.

9 June 2021 - OnLogic TM800 - 17 Comments
AMD Continues Working On SmartShift Support For Linux
AMD Continues Working On SmartShift Support For Linux

Announced last year by AMD was SmartShift Technology for laptops with both AMD CPUs and GPUs to allow dynamically shifting the power budget between the CPU/GPU depending upon the current workload. AMD promoted SmartShift as delivering up to 14% extra performance and now this technology is being worked on for their Linux driver.

1 June 2021 - AMD SmartShift - 12 Comments
AMD Preparing More Linux Code For The Frontier Supercomputer

Frontier as the first US exascale supercomputer being commissioned by Oak Ridge National Laboratory and the Department of Energy. while being powered by AMD CPUs/GPUs is in the process of seeing more Linux kernel changes for bringing up the new platform.

27 May 2021 - Kernel Changes - 12 Comments
AMD Publishes Latest Linux Patch To Toggle Predictive Store Forwarding (PSF)
AMD Publishes Latest Linux Patch To Toggle Predictive Store Forwarding (PSF)

It's been a month and a half since AMD published a security analysis of their new Zen 3 "Predictive Store Forwarding" feature that while helping performance could theoretically lead to a new side-channel attack. While they published a Linux patch to allow disabling PSF if desired for increased security, to this day they remain in the works and have yet to be mainlined.

18 May 2021 - AMD PSF Linux v6 - 5 Comments
AMD Zen 3 Scheduler Model Finally Added To LLVM/Clang

While last minute AMD Zen 3 "znver3" improvements managed to make it for GCC 11 that was recently released, the recent debut of LLVM 12.0 wasn't so lucky on the Zen 3 support front. There was the very basic enablement that landed in LLVM 12 but now the more complete support isn't expected until LLVM 13 this autumn.

3 May 2021 - Znver3 - 8 Comments
AMD Energy Driver Booted From The Linux 5.13 Kernel

While a lot of new features and improvements have been accumulating for the Linux 5.13 kernel with the ongoing merge window, one of the unfortunate aspects of this new kernel is that the AMD Zen CPU energy driver "amd_energy" is indeed being removed.

29 April 2021 - amd_energy Removed - 37 Comments

1663 AMD news articles published on Phoronix.