On Fri, 22 Oct 2010 07:55:02 -0500 Anthony Liguori <anth...@codemonkey.ws> wrote:
> On 10/22/2010 07:48 AM, Luiz Capitulino wrote: > > On Thu, 21 Oct 2010 15:27:23 +0200 > > Alon Levy<al...@redhat.com> wrote: > > > > > >> On Thu, Oct 21, 2010 at 08:13:19AM -0500, Anthony Liguori wrote: > >> > >>> On 10/21/2010 08:03 AM, Gerd Hoffmann wrote: > >>> > >>>> On 10/21/10 08:36, Alon Levy wrote: > >>>> > >>>>> v2->v3 changes: > >>>>> * add configure parameter > >>>>> * fix docs > >>>>> > >>>>> v2 message: > >>>>> This patchset uses id like device_del for attaching/detaching usb > >>>>> devices. The first two patches ready the way: > >>>>> 1. makes qdev_find_recursive non static and in qdev.h > >>>>> 2. adds a usb_device_by_id which goes over the usb buses calling > >>>>> qdev_find_recursive > >>>>> 3. adds the commands that use usb_device_by_id > >>>>> > >>>>> Alon Levy (3): > >>>>> qdev: make qdev_find_recursive public > >>>>> usb: add public usb_device_by_id > >>>>> monitor: add usb_attach and usb_detach (v2) > >>>>> > >>>>> > >>>> Acked-by: Gerd Hoffmann<kra...@redhat.com> > >>>> > >>> Okay, I am still confused about the use-case for this and I don't > >>> see any further explanation in the commit messages. I've seen > >>> "debugging" but can you be a bit more specific about which cases > >>> it's needed for? > >>> > >> To elaborate a little more, when using a certificates based card > >> there is no hardware event (i.e. removing/inserting the physical card) > >> that causes a usb_detach/attach to the card (both in passthru and > >> emulated), but otoh certificates is good for testing since it decouples > >> it from NSS/tcp. So I needed some way to emulate an insert/remove, and > >> I saw usb_del, which was pretty close, and voila. This is not the same > >> as card remove/reinsert, but it is exactly what will happen to the > >> guest when spicec connects/disconnects, since I detach devices on > >> disconnect and attach on connect. > >> > > Looks reasonable to me, specially because this will be protected by > > #ifdef DEBUG. I don't see a big deal in merging this. > > > > I'd just like to see better documentation. A command isn't useful for > debugging if noone knows how to use it. > > Guarding with an #ifdef isn't necessary. It should be unconditionally > enabled otherwise it will bit rot. You and Gerd asked about the purpose of this command, turns out that it's only useful for developing new USB devices for QEMU, so I thought it would be better to restrict it, so that people don't start using this the wrong way or worse, we can't drop/break it because some tool is now using it. Anyway, maybe a good doc will do, this was just a small suggestion. > > > Objections, Anthony? > > > > Not with better docs. > > Regards, > > Anthony Liguori > > >>> This is just adding a HMP command. Is that the right approach or > >>> was that an unintentional consequence of rebasing post-HMP/QMP > >>> split? > >>> > > I don't think this should be available under QMP, it's more a debugging > > command for USB developers. > > > > > >>> Regards, > >>> > >>> Anthony Liguori > >>> > >>> > >>>> cheers, > >>>> Gerd > >>>> > >>>> > >>>> > >>> > >>> > >> > > >
