On 3/3/26 15:26, Alex Huang wrote: > On Tue, Mar 3, 2026 at 7:30 AM Danilo Machado > <[email protected] <mailto:[email protected]>> > wrote: > > To: [email protected] > <mailto:[email protected]> > Subject: [Bug report] AMD Radeon R9 380 (Tonga) suspend resume > regression: black screen / no EDID on kernel 6.13+ (ref: Ubuntu > #2142389) > > Dear AMDGPU/DRM maintainers, > > I'm reporting a suspend/resume regression affecting the Radeon R9 > 380 (Tonga / GCN 3rd gen) on recent kernels (6.13+), observed on > Ubuntu 24.10 derivatives (Zorin OS 18) with kernel 6.17.0-14-generic.
That is a vendor kernel that contains quite a few modifications that might contain the bug you are seeing; hence please either report the problem to your vendor or check with the latest vanilla mainline kernel (e.g. 7.0-rc2; latest 6.19.y might also suffice, but better test 7.0-rc). The latter is needed anyway, as the bug might already be fixed. If the problem still happens there, you as mentioned by Alex most likely need to do a bisection to get some tracking on this. Ciao, Thorsten > A nontrivial amount of pm/EDID changes occurred between 6.12 and 6.13, > are you able to bisect the kernel between those two revisions? Even > narrowing it down to a release candidate should be useful. > > #regzbot introduced: v5.12..v5.13 > #regzbot from: Danilo Machado <[email protected] > <mailto:[email protected]>> > #regzbot monitor: https://bugs.launchpad.net/ubuntu/+source/linux/ > +bug/2142389 <https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2142389> > > Best, > Alex H > > > **Hardware:** > - GPU: AMD Radeon R9 380 Series (Tonga XT, Tonga) > - Motherboard: Gigabyte B450 AORUS PRO WIFI (BIOS F66) > - CPU: AMD Ryzen 5 5500 > - Connection: Direct HDMI > - Display server: X11 > - Power state: Deep sleep (S3) > > **Symptoms:** > - After suspend (first cycle often works; subsequent cycles fail > consistently): > - System wakes (fans/LEDs active), but display shows black > screen / no signal ("HDMI Out of Range" on monitor). > - EDID read/handshake fails → no video output recovered. > - Keyboard/mouse may respond briefly, but desktop freezes → hard > reboot required. > - Logs show: > [drm] *ERROR* HDMI-A-1: probed a monitor but no|invalid EDID > [drm] *ERROR* No EDID read. > > > **Kernels tested:** > - Broken: 6.13.12 → 6.17.0-14 (regression starts between 6.12 and 6.13) > - Stable: 6.12.74 (LTS) – suspend/resume fully reliable, no EDID errors > > **GRUB parameters used:** > quiet splash amdgpu.si_support=1 radeon.si_support=0 amdgpu.runpm=0 > amdgpu.dc=0 > > **Reference:** > This matches Ubuntu bug #2142389: https://bugs.launchpad.net/ubuntu/ > +source/linux/+bug/2142389 <https://bugs.launchpad.net/ubuntu/ > +source/linux/+bug/2142389> > (Reported by me on Launchpad; includes full dmesg logs and attachments) > > The issue appears to be in the DRM/DC layer (HDMI EDID re-detection > during multi-cycle suspend/resume on Tonga). Downgrading to 6.12.74 > resolves it completely. > > Is this a known regression? Any patches or additional debug info > needed from my side? > > Happy to test patches, provide more logs (dmesg, journalctl -b -u > systemd-suspend, full amdgpu debug), or try kernel builds. > > Thanks for your attention and work on amdgpu! > > > Tested kernels: > > 6.12.74 — stable, HDMI resume works > 6.13.12 — first resume OK, second suspend fails > 6.14.x — HDMI issues > 6.17.0-14 — frequent resume black screen > > Best regards, > Danilo Machado > Minas Gerais, Brazil > (Original reporter of Ubuntu bug #2142389) >
