I bought a PCI Express USB 3.0 card to overcome the above... invain. It performed better, in the sense that the xHCI host controller gets less often unresponsive and that it just works with iommu enabled in the BIOS as all the other USB did.
However, I STILL get a reproducible freeze up: [ 5964.638609] xhci_hcd 0000:08:00.0: xHCI host not responding to stop endpoint command. [ 5964.639671] xhci_hcd 0000:08:00.0: xHCI host controller not responding, assume dead [ 5964.639679] xhci_hcd 0000:08:00.0: HC died; cleaning up I compiled kernel 5.6-rc7 with xhci_pci and xhci_hcd as modules. This allows me to cover without rebooting: rmmod xhci_pci xhci_hcd followed by a modprobe xhci_pci recovers functionality. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1313279 Title: xHCI host not responding to stop endpoint command To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1313279/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs