On Fri, Apr 29, 2016 at 04:11:47PM +0100, Andrew Cooper wrote: > On 29/04/16 16:02, Wei Liu wrote: > > On Fri, Apr 29, 2016 at 04:21:19PM +0200, Roger Pau Monne wrote: > >> Avoid using system errno values when comparing with Xen errno values. > >> > >> Signed-off-by: Roger Pau Monné <roger....@citrix.com> > >> --- > >> Cc: Konrad Rzeszutek Wilk <konrad.w...@oracle.com> > >> Cc: Ross Lagerwall <ross.lagerw...@citrix.com> > >> Cc: Ian Jackson <ian.jack...@eu.citrix.com> > >> Cc: Wei Liu <wei.l...@citrix.com> > >> --- > >> Using errno values inside of hypercall structs is not right IMHO, but there > >> are already several occurrences of this. Although I'm adding the correct > >> XEN_ > >> prefixes here, it's very likely that new additions/modifications to this > >> file will not take this into account, breaking it for OSes != Linux. > > This seems to be a rather thorny issue. > > > > I have a gut feeling that returning XEN_ errno to userspace program is > > layering violation. They should always be translated to OS level errno > > by privcmd driver. > > > > Aren't FreeBSD and NetBSD already doing that? > > It is not practical for the privcmd driver to do this translation, as > most hypercalls through the privcmd driver are toolstack calls, and have > an unstable layout. >
If what you mean is what Roger said in his other reply then I agree translating in privcmd is not doable. > Another thorny issue is that the ioctl() call for privcmd returns errors > via errno, which may be in system errno space, or xen errno space > depending on the source of the errno. > > This is very large swamp in desperate need of some attention. > Indeed. Wei. > ~Andrew _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
