[BUG/PATCH] drivers/usb/mtu3: Work around mtu3_log_ep double-indirection issue

[Paul E. McKenney]

On Mon, Sep 21, 2026 at 03:00:45PM +0100, Mark Rutland wrote:
> On Wed, Sep 09, 2026 at 09:35:24AM -0400, Steven Rostedt wrote:
> > On Wed, 9 Sep 2026 11:31:28 +0100
> > Vladimir Murzin <vladimir.murzin at arm.com> wrote:
> > 
> > > I've done a little bit massaging and here is what worked for me
> > > 
> > > 
> > > diff --git a/drivers/usb/mtu3/mtu3_trace.h b/drivers/usb/mtu3/mtu3_trace.h
> > > index 89870175d635..4d4bae25fa1f 100644
> > > --- a/drivers/usb/mtu3/mtu3_trace.h
> > > +++ b/drivers/usb/mtu3/mtu3_trace.h
> > > @@ -224,6 +224,7 @@ DECLARE_EVENT_CLASS(mtu3_log_ep,
> > >                 __field(unsigned int, flags)
> > >                 __field(unsigned int, direction)
> > >                 __field(struct mtu3_gpd_ring *, gpd_ring)
> > > +               __field(dma_addr_t, gpd_ring_dma)
> > >         ),
> > >         TP_fast_assign(
> > >                 __assign_str(name);
> > > @@ -235,12 +236,13 @@ DECLARE_EVENT_CLASS(mtu3_log_ep,
> > >                 __entry->flags = mep->flags;
> > >                 __entry->direction = mep->is_in;
> > >                 __entry->gpd_ring = &mep->gpd_ring;
> > > +               __entry->gpd_ring_dma = mep->gpd_ring.dma;
> > >         ),
> > >         TP_printk("%s: type %s maxp %d slot %d mult %d burst %d ring %p/%pad flags %c:%c%c%c:%c",
> > >                 __get_str(name), usb_ep_type_string(__entry->type),
> > >                 __entry->maxp, __entry->slot,
> > >                 __entry->mult, __entry->maxburst,
> > > -               __entry->gpd_ring, &__entry->gpd_ring->dma,
> > > +               __entry->gpd_ring, &__entry->gpd_ring_dma,
> > >                 __entry->flags & MTU3_EP_ENABLED ? 'E' : 'e',
> > >                 __entry->flags & MTU3_EP_STALL ? 'S' : 's',
> > >                 __entry->flags & MTU3_EP_WEDGE ? 'W' : 'w',
> > 
> > LGTM,
> > 
> > Reviewed-by: Steven Rostedt <rostedt at goodmis.org>
> 
> On v7.3-rc4 I still see the splat Paul reported initially, and the above
> fixes that, so FWIW:
> 
> Tested-by: Mark Rutland <mark.rutland at arm.com>
> 
> Steve, I assume you were expecting someone to send the above as a full
> patch.
> 
> Paul, do you intend to send a v2, or should Vladimir send out his
> version as its own patch? I assume you're happy with a Reported-by, if
> he does that?

I figure that Vladimir's patch supersedes my hack, and so I would be
quite happy with Vladimir sending a formal patch with my Reported-by.

							Thanx, Paul