Blue flickering specks in main menu (on Linux with recent AMD iGPU)

[DanielGibson]

Once the mars globe in the main menu is at full size, on my Laptop (with Ryzen 7640U w/ RDNA3) I get these blue flickering specks:

The problem happens no matter if I use X11, Wayland or XWayland.

I tried it with Ubuntu 24.04 with XFCE, and a very recent Arch Linux live image with KDE.

This does not happen on:

• My old laptop with Intel Skylake iGPU
• My desktop with NVIDIA GPU
• My old desktop with Radeon RX 580 (Polaris 20)
• Yamagi's desktop with Radeon RX 5700 (Navi 10/RDNA1)
• Several GCN5/Vega-based iGPUs from people on Mastodon:
  • AMD Ryzen 7 PRO 4750U with AMD Radeon Graphics (radeonsi, renoir, LLVM 17.0.6, DRM 3.57, 6.8.8-artix1-1)
  • Ryzen 4800H w/ iGPU (Vega 7) on Manjaro Linux (X11)
  • Ryzen 7 5800H, Fedora 40, Wayland.
• Radeon RX 6700M (dedicated RDNA2)

I hope to also get feedback from people with RDNA2 or RDNA3 GPUs or iGPUs; hopefully including someone who (like me) has a Framework 13 Laptop with Ryzen 7040

By the way, the Arch Linux live system I tested was aui-kde-linux_6_8_9-0503-x64.iso from http://dl.gnutux.fr/archuseriso/iso/

I just dd'ed the ISO onto a USB memory stick, booted the laptop from it, downloaded the latest dhewm3 release and the Doom3 demo gamedata and ran dhewm3, like this:

$ wget https://github.com/dhewm/dhewm3/releases/download/1.5.3/dhewm3-1.5.3try2_Linux_amd64.tar.gz
$ tar xf dhewm3-1.5.3try2_Linux_amd64.tar.gz
$ cd dhewm3/
$ wget https://files.holarse-linuxgaming.de/native/Spiele/Doom%203/Demo/doom3-linux-1.1.1286-demo.x86.run
$ sh doom3-linux-1.1.1286-demo.x86.run --tar xf demo/
$ ./dhewm3

[slembcke]

Blue speckles confirmed on a 7840U Framework 13 w/ Fedoa 40.

glxinfo | grep "OpenGL renderer string"
OpenGL renderer string: AMD Radeon Graphics (radeonsi, gfx1103_r1, LLVM 18.1.1, DRM 3.57, 6.8.8-300.fc40.x86_64)

grep "model name" /proc/cpuinfo | head -n 1
model name	: AMD Ryzen 7 7840U w/ Radeon  780M Graphics

[DanielGibson]

Ha, I was just gonna post your findings =)
So at least it's not specific to my machine or the 7640U, but might still be specific to Framework or possibly RDNA3 or even just RDNA3 iGPUs (haven't gotten feedback from anyone with a RDNA3 dedicated GPU yet, and neither from someone with a Ryzen 8000 mobile CPU that also is RDNA3, but "Hawk Point" instead of "Phoenix")

---

I'm still especially interested in tests on:

• RDNA2 iGPUs (Ryzen 6000 mobile or 7000 desktop)
• RDNA3 iGPUs (mobile Ryzen 7x40 and 8x40 and 8x00G for desktop), esp. in other devices than Framework laptops
• dedicated RDNA3 GPUs (Radeon RX 7xxx)

[DanielGibson]

keltar on Mastodon writes:

I see this problem with discrete RX 7900 GRE, but it is fine on renoir APU. Both on X11.

So it looks like RDNA3 is generally affected, both in iGPUs and dedicated GPUs. This also implies (or at least very strongly suggests) that the iGPU-case is not Framework-specific.

Update: keltar also wrote:

booted with integrated graphics, no problem there. OpenGL renderer: AMD Radeon Graphics (radeonsi, raphael_mendocino, LLVM 17.0.6, DRM 3.57, 6.8.8-gentoo)

("integrated graphics" being the one of a Ryzen 7950X, i.e. integrated RDNA2)

So it looks like the problem is indeed RDNA3-specific and affects both integrated and dedicated GPUs.

[turol]

If it's specific to one model of GPU you should make an issue in the Mesa bug tracker.

[DanielGibson]

I would've done that either way (except maybe if it had turned out that only Framework laptops are affected, then I'd have opened an issue there), I just wanted to gather as much information as possible first :)

[DanielGibson]

By the way, the bug only happens with r_gammaInShader 1 and seems to be related to the POW shader instruction.

I created a Mesa bugreport: https://gitlab.freedesktop.org/mesa/mesa/-/issues/11144

[DanielGibson]

A workaround is to set the environment variable AMD_DEBUG=useaco before starting dhewm3.