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From: Thomas Huth <thuth@redhat.com>
Message-ID: <666c9b73-843f-3669-fe1d-69b5082b2757@redhat.com>
Date: Thu, 22 Jun 2017 08:33:35 +0200
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Subject: Re: [Qemu-devel] [PATCH 01/15] configure: add the disable-tcg option
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Yang Zhong <yang.zhong@intel.com>, anthony xu <anthony.xu@intel.com>, qemu-devel@nongnu.org, a rigo <a.rigo@virtualopensystems.com>

On 22.06.2017 08:22, Paolo Bonzini wrote:
> 
>> On 21.06.2017 12:19, Yang Zhong wrote:
>>> Add the disable-tcg option into configure and echo CONFIG_TCG=y into
>>> $config_target_mak. The default tcg is enabled for all build. If tcg
>>> is disabled in the build, only i386|x86_64 softmmu option can be disabled,
>>> other softmmu of tagets and users build defaultly enabled the tcg.
>> Why do you want to limit this disablement to x86 only? There are also
>> other architectures that support KVM (ARM, PPC, MIPS), so disabling TCG
>> might be possible there, too. So I think it might be better to check
>> whether KVM is possible instead.
> 
> You need to be careful and not use any helper from e.g. KVM or migration
> code.  So I would be very surprised if any other architecture compiles
> with --disable-tcg.

OK, fair, but we finally might want to get there, so I think we should
allow the parameter in the configure script for other architectures,
too, and then fix the bugs once we can try it out.

 Thomas