Re: [Qemu-devel] [BUG] qemu stuck when detach host-usb device

[linzhecheng]

> -----Original Message-----
> From: Gerd Hoffmann [mailto:address@hidden
> Sent: Tuesday, November 27, 2018 2:09 PM
> To: linzhecheng <address@hidden>
> Cc: address@hidden; wangxin (U) <address@hidden>;
> Zhoujian (jay) <address@hidden>; address@hidden
> Subject: Re: [Qemu-devel] [BUG] qemu stuck when detach host-usb device
> 
> On Tue, Nov 27, 2018 at 01:26:24AM +0000, linzhecheng wrote:
> > Description of problem:
> > The guest has a host-usb device(Kingston Technology DataTraveler 100
> > G3/G4/SE9 G2), which is attached to xhci controller(on host). Qemu will 
> > stuck
> if I detach it from guest.
> >
> > How reproducible:
> > 100%
> >
> > Steps to Reproduce:
> > 1.            Use usb stick to copy files in guest , make it busy working.
> > 2.            virsh detach-device vm_name usb.xml
> >
> > Then qemu will stuck for 20s, I found this is because 
> > libusb_release_interface
> block for 20s.
> > Dmesg prints:
> >
> > [35442.034861] usb 4-2.1: Disable of device-initiated U1 failed.
> > [35447.034993] usb 4-2.1: Disable of device-initiated U2 failed.
> > [35452.035131] usb 4-2.1: Set SEL for device-initiated U1 failed.
> > [35457.035259] usb 4-2.1: Set SEL for device-initiated U2 failed.
> >
> > Is this a hardware error or software's bug?
> 
> I'd guess software error, could be is libusb or (host) linux kernel.
> Cc'ing libusb-devel.
Perhaps it's usb driver's bug. Could you also reproduce it?
> 
> cheers,
>   Gerd