## Update: undocked-boot and USB-C port control tests on 7.0.0-28 I performed a controlled reboot on 2026-07-21 with the dock disconnected. I waited until the graphical desktop was running before connecting the same dock, cable, two DisplayPort monitors, and peripherals. The undocked boot did not produce the previously observed boot-time messages: - `failed to allocate DP resource for port 7` - `DMUB notification skipped due to no handler` - `DM_MST: Differing MST start` However, the post-login result depended on which laptop USB-C port was used. ### Laptop USB-C port 1 → dock rear/upstream port: failed At 09:35:56, the connection failed during the initial USB setup, before the dock, Thunderbolt topology, or displays could enumerate: ```text usb 8-1: new high-speed USB device number 2 using xhci_hcd usb 8-1: Device not responding to setup address. usb 8-1: Device not responding to setup address. usb 8-1: device not accepting address 2, error -71 No subsequent Thunderbolt, USB4, or DP MST topology appeared. Disconnecting the cable produced no device-removal event, consistent with the device never completing enumeration. ### Laptop USB-C port 2 → dock front USB-C port: no upstream event This produced no USB, USB4, Thunderbolt, or DRM hot-plug event. All external DP connectors remained disconnected. This is consistent with the dock’s front USB-C port being downstream/peripheral-facing rather than its host/upstream port. ### Laptop USB-C port 2 → dock rear/upstream port: succeeded Using the same dock, cable, displays, peripherals, running kernel, and desktop session, the dock enumerated through the second laptop USB-C port: [drm] DM_MST: starting TM [drm] DM_MST: DP14, 2-lane link detected usb 7-1: new SuperSpeed Plus Gen 2x1 USB device number 2 usb 7-1: New USB device found, idVendor=8087, idProduct=0b40 usb 7-1: Product: USB3.0 Hub The dock MCU, USB 2/3 hubs, Realtek Ethernet, dock audio, and attached Logitech C270 webcam all enumerated. Ethernet obtained carrier. Display topology discovery logged one error: amdgpu 0000:33:00.0: [drm] *ERROR* Sending link address failed with -5 The driver recovered without disconnecting the dock: [drm] Synaptics Cascaded MST hub [drm] Synaptics Cascaded MST hub [drm] MST_DSC Send DSC enable to synaptics [drm] MST_DSC Send DSC enable to synaptics Both external screens then turned on. The final DRM connector state showed DP-9 and DP-10 connected. This successful attempt did not produce: - USB error -71 - dcn31_program_compbuf_size warning - update_dpia_stream_allocation_table warning - GNOME/Mutter atomic-commit failure - complete dock disconnect/reconnect ## Interpretation These results do not support a purely boot-ordering or purely AMDGPU explanation. Booting undocked avoids the previously observed boot-time DP- resource/MST-ordering messages, but a normal post-login connection can still fail at the earliest USB setup stage on one laptop USB-C path. At that point, Thunderbolt and AMDGPU have not yet discovered the dock. The same equipment works minutes later through the second laptop USB-C port, although that successful path still produces a transient recoverable AMDGPU MST link-address error. The normal-use failure therefore appears port/path-sensitive and may involve the platform USB/XHCI/USB4 path, firmware, signal integrity, or hardware. The available evidence does not yet identify which component is responsible. Separately, the trigger_hpd_mst_set kernel oops remains a definite AMDGPU kernel-driver defect. -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2160619 Title: USB-C/USB4 dock path instability: port-dependent USB error -71, Thunderbolt disconnects, and AMDGPU DP MST failures Status in linux package in Ubuntu: New Bug description: On a Lenovo laptop with AMD Rembrandt / Radeon 680M, external monitors connected through a Lenovo ThinkPad Universal Thunderbolt 4 Smart Dock often stay dark when the system is booted while already docked. Kernel logs show repeated USB enumeration failures on the dock path, Thunderbolt dock connect/disconnect, amdgpu DP AUX/DPCD/MST link failures, and a warning in dcn31_program_compbuf_size. A manual MST reprobe via /sys/kernel/debug/dri/0000:33:00.0/amdgpu_dm_trigger_hpd_mst caused a reproducible amdgpu kernel oops in trigger_hpd_mst_set. ## Reproduction steps 1. Connect the laptop to a Lenovo ThinkPad Universal Thunderbolt 4 Smart Dock with two external DP monitors attached. 2. Boot the machine while already docked. 3. Observe that the external monitors sometimes remain dark. 4. Check kernel logs for repeated usb 8-1 enumeration failures, Thunderbolt disconnects, and amdgpu MST / AUX / DPCD errors. Additional diagnostic reproduction: 5. When the docked displays are in a working MST state, write "1" to /sys/kernel/debug/dri/0000:33:00.0/amdgpu_dm_trigger_hpd_mst. 6. Observe a kernel oops in trigger_hpd_mst_set [amdgpu]. ## Expected result The dock should enumerate cleanly during boot, both external monitors should come up reliably, and an MST hotplug reprobe should not crash the kernel. ## Actual result During docked boot, the dock path repeatedly fails USB enumeration, Thunderbolt disconnects after appearing, amdgpu DP MST link setup fails, and the external monitors may remain dark. A manual MST reprobe can trigger a kernel oops in amdgpu. ## High-signal details to include - Kernel: `7.0.0-27-generic` - GPU: `AMD Rembrandt / Radeon 680M` - BIOS: `R22ET81W (1.51)`, `2026-04-10` - Dock: `Lenovo ThinkPad Universal Thunderbolt 4 Smart Dock` - No dock firmware update was offered by `fwupdmgr` - No system firmware or EC update was pending ## Key log lines to mention These are the most important patterns: amdgpu ... [drm] DPIA AUX failed on 0x2c0(1), error 7 thunderbolt 0-2: device disconnected amdgpu ... [drm] *ERROR* dpcd_set_link_settings ... amdgpu ... [drm] *ERROR* Sending link address failed with -5 WARNING: ... dcn31_program_compbuf_size [drm:trigger_hpd_mst_set [amdgpu]] *ERROR* DM_MST: Failed to detect dc link! BUG: unable to handle page fault ... RIP: trigger_hpd_mst_set+0x13b/0x1b0 [amdgpu] ## Note The `trigger_hpd_mst_set` reprobe was used only as a diagnostic step. It should not be treated as a safe workaround, because it caused a kernel oops on this system. usb 8-1: Device not responding to setup address usb 8-1: device not accepting address ..., error -71 thunderbolt 0-2: Lenovo ThinkPad Universal Thunderbolt 4 Smart Dock ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-27-generic 7.0.0-27.27 ProcVersionSignature: Ubuntu 7.0.0-27.27-generic 7.0.6 Uname: Linux 7.0.0-27-generic x86_64 ApportVersion: 2.34.0-0ubuntu2 Architecture: amd64 CasperMD5CheckResult: pass CurrentDesktop: ubuntu:GNOME Date: Tue Jul 14 14:58:10 2026 InstallationDate: Installed on 2025-03-12 (489 days ago) InstallationMedia: Ubuntu 24.04.2 LTS "Noble Numbat" - Release amd64 (20250215) MachineType: LENOVO 21CRS08P00 ProcEnviron: LANG=en_US.UTF-8 PATH=(custom, no user) SHELL=/bin/bash TERM=xterm XDG_RUNTIME_DIR=<set> ProcFB: 0 amdgpudrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-7.0.0-27-generic root=/dev/mapper/ubuntu--vg-ubuntu--lv ro quiet splash crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M SourcePackage: linux UpgradeStatus: Upgraded to resolute on 2026-05-08 (67 days ago) dmi.bios.date: 04/10/2026 dmi.bios.release: 1.51 dmi.bios.vendor: LENOVO dmi.bios.version: R22ET81W (1.51 ) dmi.board.asset.tag: Not Available dmi.board.name: 21CRS08P00 dmi.board.vendor: LENOVO dmi.board.version: SDK0K17763 WIN dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: None dmi.ec.firmware.release: 1.33 dmi.modalias: dmi:bvnLENOVO:bvrR22ET81W(1.51):bd04/10/2026:br1.51:efr1.33:svnLENOVO:pn21CRS08P00:pvrThinkPadT14sGen3:rvnLENOVO:rn21CRS08P00:rvrSDK0K17763WIN:cvnLENOVO:ct10:cvrNone:skuLENOVO_MT_21CR_BU_Think_FM_ThinkPadT14sGen3:pfaThinkPadT14sGen3: dmi.product.family: ThinkPad T14s Gen 3 dmi.product.name: 21CRS08P00 dmi.product.sku: LENOVO_MT_21CR_BU_Think_FM_ThinkPad T14s Gen 3 dmi.product.version: ThinkPad T14s Gen 3 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2160619/+subscriptions
Комментариев нет:
Отправить комментарий