Re: [Qemu-devel] USB PCI host bus adapter hot plug

[Gonglei (Arei)]

Hi,

> Subject: [Qemu-devel] USB PCI host bus adapter hot plug
> 
> Hi!
> 
> I noticed that QMP's "device_add usb-ehci,id=i2,bus=pci.0" fails on PCI
> hotplug. The same for pci-ohci and this is because their initfn() do
> "dc->hotpluggable   = false". So I removed those and now I can hotplug USB
> hosts but none of them is able to actually work:
> 
> address@hidden:~# echo 1 >/sys/bus/pci/rescan
> [   41.143062] ohci-pci 0000:00:01.0: init err (c8700000 0000)
> [   41.143133] ohci-pci 0000:00:01.0: can't start
> [   41.143227] ohci-pci 0000:00:01.0: startup error -75
> [   41.144202] ohci-pci 0000:00:01.0: init 0000:00:01.0 fail, -75
> 
> 
> address@hidden:~# echo 1 >/sys/bus/pci/rescan
> [   43.691067] ehci-pci 0000:00:01.0: can't setup: -110
> [   43.692424] ehci-pci 0000:00:01.0: init 0000:00:01.0 fail, -110
> 
> 
> Why is that? Is QEMU just missing some bits or there is some fundamental
> issue which I just do not see? Thanks!
> 
Cc'ing Gerd.

Actually I have post a patch serials for supporting usb host adapter 
hotplugging,
Which has been involved in Gerd's (the USB mantainer) usb-next tree. Please see:
https://www.kraxel.org/cgit/qemu/log/?h=rebase/usb-next

The function of usb host adapter hotplugging is ok. You are welcome to test it.

BTW, What's your guest os type?

Best regards,
-Gonglei