Does anyone understand how HDMI 2.1 support is now no problem? I remember that 2.1 support in AMD's open source driver was blocked by the HDMI forum, but I haven't heard any news about them unblocking it. What changed?
It doesn't give any specifics about what changed on the HDMI Forum side, but this article [0] from June indicates that Valve worked closely with AMD to get it pushed through prior to the release of the Steam Machine (which supports HDMI 2.1 VRR).
As far as I can recall: some internal implementation documentation leaked which made the legal position tougher for them somehow to protect it as proprietary (it made sense when I heard it explained, but now I feel like I'm missing an important detail to that), and then Valve had some talks with the HDMI Forum to convince them to let it go, presumably so they could have such support integrated into Linux for their hardware (Deck, Machine, Frame, etc).
So now the HDMI Forum just doesn't really care anymore I guess.
IIRC, a non-AMD contributor was working on adding HDMI 2.1 support to Linux's AMD driver, and then AMD managed to get the HDMI Forum to see that their position was moot and was making things very awkward for AMD.
Oh this makes sense! Obviously, it can't be illegal for a non-forum-member to add HDMI support; it's just an HDMI forum policy after all, not law. That's certainly the link I was missing for this to make sense.
presumably someone at Valve said "either you do this or we will pay an open source contributor 100k a year to reimplement every spec you make for the rest of time"
As a long time desktop and server user, why do I look at changelogs...
New filesystems and major changes to existing ones (large performance improvements, new features like adding better compression standards which I now know I can use, fixes to long-standing bugs which open new use cases).
New protocols like wireguard when it was new and exciting (still is now that I think of it). When that was mainlined, I knew I had some network rearchitecting to do.
New device drivers like amdgpu when it was massive news. Less so these days since most hardware is well supported, and I don't buy the absolute latest.
New kernel APIs which I can use in my programs — like landlock, when it was merged I knew it was time to improve sandboxing in some of my stuff.
Though LWN and kernel newbies do it best, already linked by others.
It's a well-formatted changelog of the most salient features of the release. Linus doesn't provide one apart from a list of added commits and merged branches, which isn't very useful unless you are a kernel developer.
=USB4STREAM for streaming data with USB4=
In addition to Thunderbolt networking, which was already supported, this release adds support for streaming data directly over a cable as well (USB4STREAM). It is very simple and basically just transfers raw packets from one host to another. The driver exposes /dev/tbstreamX devices on each side of the link that can be used to transfer data using regular filesystem operations such as read(2) and write(2):
host1 # cat /dev/tbstream0
host2 # echo hello > /dev/tbstream0
This can be useful in cases where network tooling is not available or just for existing applications like dd and cat that do not support sockets. This feature can be used at the same time with thunderbolt_net so they don't rule each other out, and it allows multiple streams to be created.
I think it is mostly "marketing" for Igalia's services. If you want to pay people to do "stuff" in Linux and adjacent projects like Mesa, Igalia seems very competent.
I don't think there is much too it, it's a consulting firm. Would you hire a consulting firm with an empty tech blog portifolio? It's ticking a box, it's stating it's a consulting firm in tech, that it's target audience are companies with Linux machines etc...
It's more than that: free and open support for HDMI 2.1 in general. Previously it was only proprietary implementations that didn't leak the spec which were allowed. AMD is just the only one that has really good open source drivers which can benefit from it, and didn't work around the problem by converting HDMI to DisplayPort in a proprietary on-board GPU chip.
I can tell you mine does: a Corsair XENEON 27QHD240. Or the somewhat popular and badly named Acer Nitro XV275K P5biipruzx
I'd say it's usual for displays released in the 2-5 years old range. HDMI 2.1 got somewhat quick monitor support for consoles, but search for "first DP2.1 monitor" gets results from 2024
I have been using HDMI to game on TV for most or all of my adult life. Mostly console gaming. A few years back I built a dedicated gaming rig, but I still use it with a controller from my couch connected to a TV.
So this is a win for couch gamers and open source in general.
> DRM exposes an API that user-space programs can use to send commands and data to the GPU and perform operations such as configuring the mode setting of the display.
> User-space programs can use the DRM API to command the GPU to do hardware-accelerated 3D rendering and video decoding, as well as GPGPU computing.
The Direct Rendering Manager is useful for any Linux user who wants to display things on a monitor (unless you're happy with like 640x480 VESA, in which case maybe you don't need it)
I clicked this one with no hype. I am now exited to update the kernel of my raspberry pi 4.
Does anyone understand how HDMI 2.1 support is now no problem? I remember that 2.1 support in AMD's open source driver was blocked by the HDMI forum, but I haven't heard any news about them unblocking it. What changed?
It doesn't give any specifics about what changed on the HDMI Forum side, but this article [0] from June indicates that Valve worked closely with AMD to get it pushed through prior to the release of the Steam Machine (which supports HDMI 2.1 VRR).
[0] https://www.digitalfoundry.net/news/2026/06/valves-hdmi-2-1-...
As far as I can recall: some internal implementation documentation leaked which made the legal position tougher for them somehow to protect it as proprietary (it made sense when I heard it explained, but now I feel like I'm missing an important detail to that), and then Valve had some talks with the HDMI Forum to convince them to let it go, presumably so they could have such support integrated into Linux for their hardware (Deck, Machine, Frame, etc).
So now the HDMI Forum just doesn't really care anymore I guess.
IIRC, a non-AMD contributor was working on adding HDMI 2.1 support to Linux's AMD driver, and then AMD managed to get the HDMI Forum to see that their position was moot and was making things very awkward for AMD.
Oh this makes sense! Obviously, it can't be illegal for a non-forum-member to add HDMI support; it's just an HDMI forum policy after all, not law. That's certainly the link I was missing for this to make sense.
presumably someone at Valve said "either you do this or we will pay an open source contributor 100k a year to reimplement every spec you make for the rest of time"
White collar crime is legal now so IP violation is a pretend concept.
Update - Happily eating the downvotes on this one.
Only if an AI does it, so make sure the vibe code the driver
Who is the main audience for this type of content? Genuinely curious because I am not a serious Linux user.
What type of info do you get out of this for those who read this? So i can glance your insight?
As a long time desktop and server user, why do I look at changelogs...
New filesystems and major changes to existing ones (large performance improvements, new features like adding better compression standards which I now know I can use, fixes to long-standing bugs which open new use cases).
New protocols like wireguard when it was new and exciting (still is now that I think of it). When that was mainlined, I knew I had some network rearchitecting to do.
New device drivers like amdgpu when it was massive news. Less so these days since most hardware is well supported, and I don't buy the absolute latest.
New kernel APIs which I can use in my programs — like landlock, when it was merged I knew it was time to improve sandboxing in some of my stuff.
Though LWN and kernel newbies do it best, already linked by others.
It's a well-formatted changelog of the most salient features of the release. Linus doesn't provide one apart from a list of added commits and merged branches, which isn't very useful unless you are a kernel developer.
This isn't quite right.
This is a well-formatted changelog of the changes that Igalia has contributed to the release, AFAICT.
KernelNewbies publishes a much more general summary of changes (it is much longer than this one).
https://kernelnewbies.org/LinuxChanges
https://kernelnewbies.org/LinuxVersions
What great resource thank you !
This new thing is pretty cool :
It only covers changes made by Igalia devs. For a more general changelog I’d recommend the LWN articles:
https://lwn.net/Articles/1078068/ https://lwn.net/Articles/1078539/
ty for the context. I was not aware of the Linux dev ecosystem.
I think it is mostly "marketing" for Igalia's services. If you want to pay people to do "stuff" in Linux and adjacent projects like Mesa, Igalia seems very competent.
hi audience, we know about this stuff you use on a daily basis, you may be interested in our executive summary of the latest release of the stuff
I don't think there is much too it, it's a consulting firm. Would you hire a consulting firm with an empty tech blog portifolio? It's ticking a box, it's stating it's a consulting firm in tech, that it's target audience are companies with Linux machines etc...
ty. so very narrow audicence it seems.
Per @sph, as Linus provide no changelog, seems like the firm is putting it together for others
I for one am excited about HDMI 2.1 support on AMD.
It's more than that: free and open support for HDMI 2.1 in general. Previously it was only proprietary implementations that didn't leak the spec which were allowed. AMD is just the only one that has really good open source drivers which can benefit from it, and didn't work around the problem by converting HDMI to DisplayPort in a proprietary on-board GPU chip.
OK, now this is what I wanted to know as well. I was not aware that changelogs show all this inf.
ty for sharing
Okay, so ELI 5 why I would now use HDMI instead of DP?
All my monitors support DP, my GPU has more ports for DP ...
I am genuinely interested as I've never even considered using HDMI for my Desktop.
If you’re using a TV. They rarely have DP ports.
HDMI is a king on consumer TVs. Linux (in form of SteamOS) is becoming a major console gaming platform thanks to Valve.
Because your motherboard only supports HDMI. The last three I used had HDMI, and sometimes VGA.
HDMI 2.1 carries more bandwidth than DisplayPort 1.4. Plenty of GPU/monitors have that port arrangement, as recent as Nvidia's RTX 40 Series.
Yeah but this is for amdgpu and they had DP2.1 support for a while now.
That doesn't help when the monitors don't have DP2.1 support.
I havent seen a monitor (besides tvs) that has HDMI2.1 but not DP2.1
I can tell you mine does: a Corsair XENEON 27QHD240. Or the somewhat popular and badly named Acer Nitro XV275K P5biipruzx
I'd say it's usual for displays released in the 2-5 years old range. HDMI 2.1 got somewhat quick monitor support for consoles, but search for "first DP2.1 monitor" gets results from 2024
And that parenthetical is exactly why people care.
TVs.
I have been using HDMI to game on TV for most or all of my adult life. Mostly console gaming. A few years back I built a dedicated gaming rig, but I still use it with a controller from my couch connected to a TV.
So this is a win for couch gamers and open source in general.
Great context, thanks for adding it
Sounds like an AI comment.
Why is DRM being implemented in the Kernel; What is the profile for an end-user who wants this in their FOSS?
Here it doesn’t mean “digital rights management”, but “Direct Rendering Manager”, a component of the kernel’s graphics stack: https://docs.kernel.org/gpu/?utm_source=chatgpt.com
People who want to play video games, or watch videos using hardware decoding, or train machine learning models? DRM here means https://en.wikipedia.org/wiki/Direct_Rendering_Manager
> DRM exposes an API that user-space programs can use to send commands and data to the GPU and perform operations such as configuring the mode setting of the display.
> User-space programs can use the DRM API to command the GPU to do hardware-accelerated 3D rendering and video decoding, as well as GPGPU computing.
The Direct Rendering Manager is useful for any Linux user who wants to display things on a monitor (unless you're happy with like 640x480 VESA, in which case maybe you don't need it)
This is DRM as in Direct Rendering Manager, which is the kernel interface to GPU hardware; not Digital Rights Management.
Named long before Digital Rights Management was a thing (or at least the 3 letter acronym existed for it).
Different DRM, the one in the kernel is Direct Rendering Manager, which is basically managing access to the GPU.
DRM refers to Direct Rendering Manager in this context.
DRM = Direct Rendering Manager. GPU scheduling.
its the Direct Rendering Manager, not the other DRM