Re: [PATCH] libxc: make unlock_page return error

[Christoph Egger <Christoph.Egger@amd.com>]

On Thursday 19 August 2010 16:57:21 Ian Campbell wrote:
> On Thu, 2010-08-19 at 15:46 +0100, Ian Jackson wrote:
> > Christoph Egger writes ("[Xen-devel] [PATCH] libxc: make unlock_page 
return error"):
> > > As a result of debugging 'xend segfaults when starting',
> > > the attached patch makes unlock_pages return an error.
> >
> > Having read this in more detail, it seems that you're making
> > {lock,unlock}_pages return errno values on error.  That's fine but
> > it's quite unusual in libxc; all libxc functions normally return -1 on
> > error and set errno.
> >
> > So I think the unusual return value convention is worth a comment in
> > xc_private.h.  Can you please resubmit with such a comment ?
>
> I think it should just follow the normal libxc convention instead of
> commenting on the use of an unusual return value convention.
>
> I also think that such a patch must include (or be part of a series
> which) updates the callers to actually do something with the new return
> value, or else it is somewhat pointless.
>
> Given that this patch was only for debugging purposes for an issue which
> is now resolved is there any need?

The need I see for now is a future regression.

Christoph



-- 
---to satisfy European Law for business letters:
Advanced Micro Devices GmbH
Einsteinring 24, 85609 Dornach b. Muenchen
Geschaeftsfuehrer: Alberto Bozzo, Andrew Bowd
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632