On Thu, May 30, 2013 at 05:05:51PM +0200, Laszlo Ersek wrote:
> On 05/30/13 15:27, Michael S. Tsirkin wrote:
> > Use the type-safe FWCfgState structure instead
> > of the unsafe void *.
> >
> > Signed-off-by: Michael S. Tsirkin <m...@redhat.com>
> > ---
> > hw/misc/pvpanic.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/hw/misc/pvpanic.c b/hw/misc/pvpanic.c
> > index 31e1b1d..1483f27 100644
> > --- a/hw/misc/pvpanic.c
> > +++ b/hw/misc/pvpanic.c
> > @@ -90,7 +90,7 @@ static int pvpanic_isa_initfn(ISADevice *dev)
> > {
> > PVPanicState *s = ISA_PVPANIC_DEVICE(dev);
> > static bool port_configured;
> > - void *fw_cfg;
> > + FWCfgState *fw_cfg;
> >
> > memory_region_init_io(&s->io, &pvpanic_ops, s, "pvpanic", 1);
> > isa_register_ioport(dev, &s->io, s->ioport);
> >
>
> Doesn't this break your build? Lower down in the function there's
>
> fw_cfg = object_resolve_path("/machine/fw_cfg", NULL);
>
> and object_resolve_path() returns a pointer-to-Object, not
> pointer-to-FWCfgState.
I see, I think I should reorder the patches.
> But for starters I'm quite confused about how the unpatched function
> works. What it does amounts to:
>
> fw_cfg_add_file(object_resolve_path(...), ...);
>
> But, again object_resolve_path() returns pointer-to-Object. I'm checking
> "struct Object" in "include/qom/object.h", and it suggests that derived
> structs should embed Object as first member. However FWCfgState is *not*
> such a derived member. What's going on here?
>
> http://thread.gmane.org/gmane.comp.emulators.qemu/201544/focus=201564
> http://thread.gmane.org/gmane.comp.emulators.qemu/204452/focus=204450
>
> Laszlo
