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Date: Wed, 8 Jul 2015 20:30:42 +0300
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [RFC v3 7/8] memory: extend
 memory_region_add_subregion() to support error reporting
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To: Igor Mammedov <imammedo@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, QEMU Developers <qemu-devel@nongnu.org>, Paolo Bonzini <pbonzini@redhat.com>

On Wed, Jul 08, 2015 at 04:58:37PM +0200, Igor Mammedov wrote:
> On Wed, 8 Jul 2015 12:09:10 +0100
> Peter Maydell <peter.maydell@linaro.org> wrote:
> 
> > On 8 July 2015 at 10:46, Igor Mammedov <imammedo@redhat.com> 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 <imammedo@redhat.com>
> > >  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.

-- 
MST