## Update (2026-09-17): dock/network killed on hibernation *resume* (not entry) — same amdgpu/TTM bug, new failure surface
Hibernate cycle this time completed the entry/write phase normally (`PM: hibernation: hibernation exit` logged ~50min after entry — the earlier `Filesystems sync` freeze from the previous update did not recur, possibly due to the `HibernateMode=shutdown` workaround applied in the meantime, though this update shows that workaround does not address the failure mode below). The failure happens in the first second after resume: 1. The same `WARNING: ttm_resource_add_bulk_move` (ttm_resource.c:235, amdgpu/TTM) from the previous update fires again, repeated hundreds of times in a tight loop. 2. Followed by an amdgpu-initiated **MODE2 reset** (driver's own defensive full GPU reset). 3. All 4 USB root hubs report "lost power or was reset" at the same instant, and — notably, since this rules out a dock/peripheral-specific cause — the **Wi-Fi chip** (`mt7921e`) independently fails with `PM: failed to restore async: error -110` (timeout) at the very same moment. 4. The Ethernet chip inside a docked Dell WD19 (USB-C, `r8152` driver) fails to probe: register read timeout (`-110`), then USB reset also fails (`-22`), driver gives up, device disconnects permanently. 5. No further USB/network/GPU activity logged until a manual hard reboot ~6 minutes later — matches the observed symptom (only USB-C charging kept working; charging is negotiated by a separate PD controller, independent of the OS-managed USB/PCIe stack that was left broken). ## Interpretation This is not a dock- or network-specific bug — it's the same underlying amdgpu/TTM issue already reported here (previously observed as a full system freeze), this time surfacing as a partial USB/PCIe fabric failure on resume instead of a total hang. The Wi-Fi chip failing with the identical -110 timeout at the identical instant, despite being architecturally unrelated to the USB dock, indicates the disruption is at the shared bus/fabric level triggered by the GPU's MODE2 reset, not in any individual peripheral driver. ## Hardware/software (unchanged) Dell Inspiron 14 5425, AMD Ryzen 7 5825U, AMD Barcelo iGPU (amdgpu), BIOS 1.29.0, kernel 7.0.0-31-generic, Ubuntu, KDE Plasma 6.5, Wayland. Docked via Dell WD19 (USB-C). NB : hibernation via solution described here : https://github.com/FrameworkComputer/SoftwareFirmwareIssueTracker/issues/261 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2161312 Title: System hangs on suspend (s2idle) with kernel 7.0.0-28-generic, works fine on 7.0.0-27 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2161312/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
