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From: Thomas Huth <thuth@redhat.com>
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Date: Wed, 5 Jul 2017 13:58:35 +0200
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Subject: Re: [Qemu-devel] change x86 default machine type to Q35?
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To: Fam Zheng <famz@redhat.com>, "Daniel P. Berrange" <berrange@redhat.com>
Cc: Chao Peng <chao.p.peng@linux.intel.com>, "Tian, Kevin" <kevin.tian@intel.com>, qemu-devel@nongnu.org

On 05.07.2017 13:44, Fam Zheng wrote:
> On Wed, 07/05 12:04, Daniel P. Berrange wrote:
>> While you can say people should just add '-M pc' that isn't a nice
>> user experiance, because it makes the assumption that people actually
>> understand what caused their breakage. When the incompatibilities
>> arise the error messages are unlikely to give any hint to users that
>> the problems are caused by the machine type change. So unless someone
>> is very familiar with debugging QEMU, they're not going to realize
>> that '-M pc' will fix their problem.
> 
> While we change the default, can we start to print a message like 'machine type
> ("-M" option) not specified, default to Q35. If you find compatibility issues,
> try "-M pc"'?

Or we could simply remove the default machine type completely for a
couple of releases? That would force people to update their script with
"-M pc" ... and once this has been established, we can finally make q35
the default?

 Thomas