On Sat, Mar 08, 2025 at 12:57:22AM GMT, Kirill A. Korinsky wrote:

> On Fri, 07 Mar 2025 21:39:30 +0100,
> Marcus Glocker <marcus@nazgul.ch> wrote:
> >
> > On Thu, Mar 06, 2025 at 09:12:55AM GMT, Kirill A. Korinsky wrote:
> >
> > > tech@,
> > >
> > > I'd like to fix a crash in uvide when I detach my Elgato webcam when
> > > it's streamming.
> > >
> > > uvideo_vs_close is called from videoclose and by VIDIOC_STREAMOFF. When
> > > it's happened on detached webcam with isochronous endpoint, the system
> > > crashes inside usbd_set_interface.
> > >
> > > Ok?
> >
> > Usually we're using usbd_is_dying() to return from a function at the
> > very beginning.  Would it also work in your case to return from
> > uvideo_vs_close() at the very beginning instead of only wrapping it
> > around usbd_set_interface()?
> >
> 
> Well, I assume that usually driver doesn't sleep before call set interface.
> 
> I had tried to move usbd_is_dying(sc->sc_udev) to the first line of
> uvideo_vs_close, and it crashed inside usbd_set_interface().
> 
> And when I had moved it back, after sleep, it works.

I see.  Which indicates that at the beginning of uvideo_vs_close()
usbd_is_dying() isn't set.  Probably the usb state converts to dying
after the delay in your case.

I'm basically OK with that then, and it shouldn't have regression to
other devices.

Just one style thing;  Can you please move the comment above the 'if'
to avoid line break?