Re: [Qemu-devel] [RFC v3 7/8] memory: extend memory_region_add_subregion() to support error reporting

[Igor Mammedov]

On Wed, 8 Jul 2015 20:30:42 +0300
"Michael S. Tsirkin" <address@hidden> wrote:

> On Wed, Jul 08, 2015 at 04:58:37PM +0200, Igor Mammedov wrote:
> > On Wed, 8 Jul 2015 12:09:10 +0100
> > Peter Maydell <address@hidden> wrote:
> > 
> > > On 8 July 2015 at 10:46, Igor Mammedov <address@hidden>
> > > wrote:
> > > > extends memory_region_add_subregion() by adding Error**
> > > > argument to allow t fail and return a error from it.
> > > >
> > > > Signed-off-by: Igor Mammedov <address@hidden>
> > > >  156 files changed, 619 insertions(+), 420 deletions(-)
> > > 
> > > This is a seriously invasive API change and I don't
> > > really like it -- reconfiguring the memory region
> > > hierarchy should not be an operation which can fail
> > > (especially not just adding a subregion!)
> > > 
> > > -- PMM
> > > 
> > 
> > I'll drop this patch in favor of dedicated
> > memory_region_add_subregion_to_hva() API that can fail and return
> > error.
> 
> Personally, I think it would be better to have an API that gets
> a hva and a callback to invoke before releasing MR.
> 
> It's just a question of taste though.
> 

that won't handle check at subregion_add time if region is available
and error out if it's.