Re: [Qemu-devel] [PATCH] i386: Support "-cpu host" on TCG too

[Peter Maydell]

On 19 January 2017 at 17:50, Daniel P. Berrange <address@hidden> wrote:
> On Mon, Jan 16, 2017 at 05:54:52PM -0200, Eduardo Habkost wrote:
>> Change the meaning of "-cpu host" to "enable all features
>> supported by the accelerator in the current host", so that it can
>> be used to enable/query all features supported by TCG.
>>
>> To make sure "host" is still at the end of the list in "-cpu
>> help", add a "ordering" field that will be used when sorting the
>> CPU model list.
>
> To be clear, "-cpu host" for TCG is not talking about the actual
> host OS feature support, right ? x86_64 TCG can be run on a ppc host,
> so presumably "-cpu host" just means "all features that this TCG binary
> is able to emulate" ?
>
> This feels like it is introducing scope for confusion vs KVM -cpu host,
> so I wonder if different naming is better for this.

The idea is that you do want an option that works whatever the
accelerator is, though, so as a user you don't need to worry
about messing with the command line for KVM vs TCG vs "try
KVM and fall back to TCG". (I think "-cpu best" has been thrown about
as a suggestion for this before.)

thanks
-- PMM