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From: Mark Kanda <mark.kanda@oracle.com>
Message-ID: <9d62856a-0148-d3a2-6401-c8ff29b71ed3@oracle.com>
Date: Wed, 27 Feb 2019 21:58:48 -0600
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Subject: Re: [Qemu-devel] Nested SVM only enabled (by default) in
 pc-i440fx-2.1?
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To: qemu-devel@nongnu.org

On 2/27/2019 4:05 PM, Mark Kanda wrote:
> Hi all,
>=20
> I noticed nested SVM is enabled only in pc-i440fx-2.1 (default is=20
> disabled); this was added when 2.1 was the latest:
>=20
>  =C2=A0=C2=A0=C2=A0=C2=A075d373ef97 ("target-i386: Disable SVM by defau=
lt in KVM mode")
>=20
> However, this change was not carried forward to newer machine types. Is=
=20
> this an oversight? Is there a reason we (still) need SVM disabled by=20
> default?

To clarify, it's my understanding the above patch was added to disable=20
nested SVM in pc-i440fx-2.2 (and future) machine types due to stability=20
issues (while keeping it enabled in pc-i440fx-2.1 and previous machine=20
types).

I'm wondering if nested SVM is now mature enough to remove this=20
restriction and enable it by default (at least on recent machine types).

Thanks/regards,
-Mark