On Thu, 7 Jun 2018 18:06:26 +0200 Gerd Hoffmann <kraxel@xxxxxxxxxx> wrote: > Hi, > > > left it in a state that we're not recovering from. For root complex > > integrated endpoints, if there's no FLR or even PM reset available, > > you're out of luck unless you can come up with a device specific > > reset. > > Should be doable, ehci has a controller reset bit in the command > register (xhci too btw). > > Typically doing a reset is one of the first things a driver does on > initialization though. So I'm not fully sure such a reset quirk would > improve the situation ... Do SeaBIOS/edk2 drivers make use of those resets as well? It seems like when I've seen trouble with assigned USB devices, it's often at the VM BIOS. In any case, if there are USB specific standards here, we should hook them in through pci_dev_specific_reset() in the host kernel. I imagine we'd try to prioritize these lower than a PCI FLR, but certainly better than nothing. Thanks, Alex
