Linux 7.3 Adds DRM Format Modifier Support for Older AMD GPUs
Linux 7.3 kernel introduces DRM format modifier support for AMD Radeon GPUs from GFX6 to GFX9 generations, led by Valve's Timur Kristóf.
A new set of patches for the AMDGPU/AMDKFD driver, targeting the Linux 7.3 kernel, was released this week. As the deadline for adding new features to Linux 7.3 approaches next month, this pull request includes particularly noteworthy updates.
A Lifeline for Legacy GPUs
The most significant addition is the implementation of DRM format modifier support for AMD GPUs from the GFX6 to GFX9 generations. This update covers video cards ranging from the Radeon HD 7000 series (GCN 1.0) to those based on Polaris and Fiji architectures. DRM format modifiers provide detailed information about image buffer attributes, including tiling, compression, and layout, which can enable higher performance and diverse use cases.
This implementation was spearheaded by Timur Kristóf, a member of Valve’s open-source Linux graphics driver team. Valve, which has been actively enhancing the Linux gaming ecosystem through projects like Steam Deck and Proton, extends its contributions naturally in this direction.
Technical Significance and Broader Impact
With support for DRM format modifiers, Vulkan-based Wayland compositors, Zink (an OpenGL-on-Vulkan layer) compositors, and interoperability between various graphics APIs will see significant improvements. Previously, older GPUs lacked format modifier support, which limited their ability to fully benefit from modern graphics stacks.
As the adoption of Wayland grows in Linux desktop environments, more Vulkan-based compositors are being developed. Ensuring optimal buffer management on older GPUs directly enhances user experience. Additionally, OpenGL applications running through the Zink layer are expected to perform better and become more stable.
Additional Fixes and Optimizations
This week’s AMDGPU/AMDKFD pull request also includes the following changes:
- Fixes for Apple Studio Display compatibility when connected to AMD GPUs.
- Optimizations for GEM (Graphics Execution Manager) close processes.
- Updates to the DCN 4.2 display core IP.
- Removal of outdated BUG() calls.
- Numerous bug fixes across both drivers.
The DCN 4.2 updates could be interpreted as preparations for future AMD GPU architectures. The removal of old BUG() macros is part of ongoing efforts to enhance kernel quality.
Valve’s Contributions and Ecosystem Impact
Valve’s active involvement in the Linux kernel’s graphics stack is clear. The AMD APU used in the Steam Deck belongs to the GFX9 generation, making it crucial to foster the ecosystem surrounding these GPUs. Allocating engineering resources to improve drivers for older GPU generations reflects Valve’s strategic decision to expand the developer community’s reach.
Timur Kristóf has a history of significant contributions to the core parts of the AMDGPU driver. The addition of DRM format modifier support is another milestone in his ongoing efforts.
Extending the Lifespan of Older Hardware
While GPUs from the GFX6 to GFX9 generations are no longer in production, they remain in widespread use by many users. Radeon HD 7000, R9 300, and RX 400/500 series GPUs, in particular, are still widely available in the second-hand market, making them valuable options for Linux users. With DRM format modifier support, systems equipped with these GPUs can now leverage the latest graphics stacks.
Modern Vulkan Wayland compositors, such as Gamescope and River, depend on format modifiers. Previously, these compositors faced functionality limitations on older GPUs, but this update alleviates those issues. OpenGL applications running through Zink are also expected to benefit from improved stability and performance.
Also Coming in Linux 7.3
The same kernel release will also include security-related changes, such as AF_ALG Restriction Enhancements and a New sysctl in Linux 7.3. This update introduces a new sysctl parameter to restrict the use of AF_ALG sockets. Both changes are positioned as major updates in the Linux 7.3 kernel.
Editorial Opinion
In the short term, Linux users with GPUs from the GFX6 to GFX9 generations will see improved compatibility with Wayland compositors and Vulkan-based applications. Environments leveraging Zink are poised to benefit from better OpenGL performance, making it easier for older hardware to take advantage of modern graphics stacks. The Apple Studio Display fixes add practical value for users with specific hardware configurations.
Over the long term, Valve’s commitment to improving drivers for legacy GPUs enhances the sustainability of the Linux gaming ecosystem. While new GPUs continue to be released, extending the lifespan of older GPU systems introduces flexibility into users’ hardware upgrade cycles. Furthermore, the standardization of DRM format modifiers could improve compatibility across GPU vendors.
From the editorial perspective, this update demonstrates the importance of long-term support from kernel maintainers and highlights the collaborative nature of the open-source community.
References
- “DRM Format Modifiers For Old AMD GPUs Coming With Linux 7.3: Thanks Valve”, by Michael Larabel — Phoronix, 2026-07-29T20:47:11.000Z (ARR)
- Source URL: https://www.phoronix.com/news/Linux-7.3-AMDGPU-GFX6-Modifiers
Frequently Asked Questions
- What are DRM format modifiers?
- DRM format modifiers describe the memory layout of image buffers, such as tiling methods, compression formats, and pitch. They enable efficient buffer sharing between different graphics APIs and compositors, especially in Vulkan and Wayland environments.
- Which AMD GPUs are covered?
- GPUs from the GFX6 to GFX9 generations. Specifically, this includes the Radeon HD 7000 series (GCN 1.0), Polaris (RX 400/500 series), and Fiji (R9 Fury series), among others using the GCN architecture.
- When will the Linux 7.3 kernel be released?
- It is expected to be released around August 2026. The deadline for new features will close in a few weeks, followed by a merge window. Based on the usual release cycle, a late August to early September release is anticipated.
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