Comment 20 for bug 1313279

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.