Root cause appears to be a packaging error in 0ubuntu3.4: the DCN 4.0.1 DMCUB firmware is shipped as a symlink to the DCN 3.2.0 (RDNA3) blob.
0ubuntu3.4: /lib/firmware/amdgpu/dcn_4_0_1_dmcub.bin.zst -> dcn_3_2_0_dmcub.bin.zst 0ubuntu3.3: /lib/firmware/amdgpu/dcn_4_0_1_dmcub.bin.zst (regular file, 225553 bytes) With 3.4 the PSP rejects it: [drm] Loading DMUB firmware via PSP: version=0x07002F00 failed to load ucode DMCUB(0x3F) psp gfx command LOAD_IP_FW(0x6) failed and response status is (0x11) With 3.3 the same card loads DMUB version=0x0A000800 and works. Affects all DCN 4.0.1 (RDNA4) cards, which matches the 9070 XT and 9060 XT reports here. Also reproduced on kernel 7.0.0-38, so it is not kernel-specific. Hardware: AMD RX 9070 [1002:7550], ASRock X470 Taichi, Linux Mint 22.3, kernel 7.0.0-42-generic. Workaround: install 0ubuntu3.3 from Launchpad, then sudo apt-mark hold linux-firmware-amd-graphics sudo update-initramfs -u -k all Confirmed: after the downgrade + hold + update-initramfs, normal boot works again on kernel 7.0.0-42 (DMUB 0x0A000800, no DMCUB errors). -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2173612 Title: [regression] linux-firmware-amd-graphics 0ubuntu3.4: DMCUB errors flood log, desktop stutters/freezes on RX 9070 XT (noble) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-firmware/+bug/2173612/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
