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Date: Tue, 3 Oct 2017 10:37:05 -0300
From: Eduardo Habkost <ehabkost@redhat.com>
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Subject: Re: [Qemu-devel] [PATCHv2] dma/i82374: avoid double creation of
 i82374 device
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Eduardo Otubo <otubo@redhat.com>, qemu-devel@nongnu.org, qemu-trivial@nongnu.org, Michael Tokarev <mjt@tls.msk.ru>, Alexander Graf <agraf@suse.de>, Markus Armbruster <armbru@redhat.com>

On Mon, Oct 02, 2017 at 02:50:07PM +0200, Paolo Bonzini wrote:
> On 29/09/2017 21:31, Eduardo Habkost wrote:
> >> -void DMA_init(ISABus *bus, int high_page_enable)
> >> +void DMA_init(ISABus *bus, int high_page_enable, Error **errp)
> > 
> > If you make the function return a boolean to indicate success (in
> > addition to setting *errp), you avoid the need for a local_err
> > variable on the caller.
> 
> I think in this case, rather than a bool, it would be better to return 0
> or -EBUSY.  A check for "< 0" would be more self-explanatory in the caller.

I'm OK with that, too.

We really need to document the available and preferred error
reporting styles somewhere (probably on qapi/error.h).  We
discussed that a lot recently[1], but the conclusions were not
documented anywhere.

[1] https://www.mail-archive.com/qemu-devel@nongnu.org/msg461702.html

-- 
Eduardo