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From: Markus Armbruster <armbru@redhat.com>
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Date: Tue, 22 Aug 2017 15:00:19 +0200
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	(=?utf-8?Q?=22Marc-Andr=C3=A9?= Lureau"'s message of "Tue, 22 Aug 2017
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Subject: Re: [Qemu-devel] [RFC PATCH 04/56] char: Make ringbuf-read size
 unsigned in QAPI/QMP
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To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau <marcandre.lureau@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Fam Zheng <famz@redhat.com>, "open list:Block layer core" <qemu-block@nongnu.org>, Juan Quintela <quintela@redhat.com>, jcody <jcody@redhat.com>, QEMU <qemu-devel@nongnu.org>, "Dr. David Alan Gilbert" <dgilbert@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, Max Reitz <mreitz@redhat.com>, John Snow <jsnow@redhat.com>

Marc-Andr=C3=A9 Lureau <marcandre.lureau@gmail.com> writes:

> Hi
>
> On Mon, Aug 7, 2017 at 4:45 PM, Markus Armbruster <armbru@redhat.com> wro=
te:
>> Sizes should use QAPI type 'size' (uint64_t).  ringbuf-read parameter
>> @size is 'int' (int64_t).  qmp_ringbuf_read() rejects negative values,
>> then implicitly converts to size_t.
>>
>> Change the parameter to 'size' and drop the check for negative values.
>>
>> ringbuf-read now accepts size values between 2^63 and 2^64-1.  It
>> accepts negative values as before, because that's how the QObject
>> input visitor works for backward compatibility.
>>
>
> Negative values over json will be implicitly converted to positive
> values with this change, right? Or are they rejected earlier?

Yes.  For details, see my reply to Juan's review of PATCH 15.

> If so that is a change of behaviour that I am not sure is worth doing
> now (without explicit protocol break), but I don't mind.