Attaching dmesg showing failed thunderbolt attachment. There is a good hotplug starting with
[35304.659358] thunderbolt 0-1: new device found, vendor=0x108 device=0x1630 [35304.659361] thunderbolt 0-1: Lenovo ThinkPad Thunderbolt 3 Dock for example, you can see that the system discovers the downstream USB controller and USB audio device that is part of the dock: [35305.406824] xhci_hcd 0000:0b:00.0: xHCI Host Controller [35305.406831] xhci_hcd 0000:0b:00.0: new USB bus registered, assigned bus number 3 ... [35306.102685] usb 3-1: New USB device found, idVendor=17ef, idProduct=306a, bcdDevice=28.00 [35306.102688] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 [35306.102691] usb 3-1: Product: ThinkPad Thunderbolt 3 Dock USB Audio then there are a few suspend/resume cycles, and a second hotplug of the thunderbolt dock: [40222.796009] thunderbolt 0-1: new device found, vendor=0x108 device=0x1630 [40222.796010] thunderbolt 0-1: Lenovo ThinkPad Thunderbolt 3 Dock in this case PCI bus enumeration seems to fail: [40223.479357] pci 0000:0a:00.0: devices behind bridge are unusable because [bus 0b] cannot be assigned for them [40223.479371] pci 0000:09:00.0: devices behind bridge are unusable because [bus 0a] cannot be assigned for them [40223.479397] pci 0000:0a:00.0: devices behind bridge are unusable because [bus 0b] cannot be assigned for them [40223.479411] pcieport 0000:07:02.0: bridge has subordinate 0a but max busn 0b [40223.479459] pci_bus 0000:3d: busn_res: can not insert [bus 3d-70] under [bus 07-0b] (conflicts with (null) [bus 07-0b]) [40223.479462] pcieport 0000:07:04.0: PCI bridge to [bus 3d-70] [40223.479470] pcieport 0000:07:04.0: bridge window [mem 0xd4000000-0xe9ffffff] [40223.479475] pcieport 0000:07:04.0: bridge window [mem 0x90000000-0xb9ffffff 64bit pref] [40223.479476] pcieport 0000:07:04.0: devices behind bridge are unusable because [bus 3d-70] cannot be assigned for them ** Tags added: kernel-bug-exists-upstream ** Attachment added: "thunderbolt-failure-dmesg.txt" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1825395/+attachment/5258054/+files/thunderbolt-failure-dmesg.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1825395 Title: thunderbolt / PCIe hotplug gets confused after a few cycles on X1 Yoga 2nd gen To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1825395/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs