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From: Chris Friesen <chris.friesen@windriver.com>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] [Bug 1248959] Re: pdpe1gb flag is missing in guest running on Intel h/w
Date: Wed, 21 Jun 2017 12:25:48 -0600	[thread overview]
Message-ID: <594ABA2C.2060504@windriver.com> (raw)
In-Reply-To: <149806671142.3407.13126852924519842175.malone@gac.canonical.com>

On 06/21/2017 11:38 AM, Anatol Pomozov wrote:
> I observe the same situation. My host CPU (Intel Xeon CPU E5-2690)
> supports 1gb pages but qemu keeps it disabled by default. I have to use
> either '-cpu phenom' or '-cpu host' with KVM.
>
> It makes me wondering what is the default CPU for QEMU? Is it possible
> to set qemu CPU featureset closer to what host CPU has?

As I understand it there is no well-defined default CPU for qemu that is 
guaranteed to be stable across versions.

Last I checked if you use the default CPU model then you get something that 
calls itself "qemu64", but explicitly setting the "qemu64" cpu model doesn't 
work when enabling kvm support on an Intel host CPU, because it wants the "svm" 
CPU feature.  (Does this strike anyone else as inconsistent?)

The "kvm64" CPU model works on Intel, but doesn't provide as many CPU features 
as what you get if you don't specify a model.

Chris

  reply	other threads:[~2017-06-21 18:26 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-11-07 13:39 [Qemu-devel] [Bug 1248959] [NEW] pdpe1gb flag is missing in guest running on Intel h/w Vladimir Zinovjevs
2017-06-21 17:38 ` [Qemu-devel] [Bug 1248959] " Anatol Pomozov
2017-06-21 18:25   ` Chris Friesen [this message]
2020-08-07  9:33 ` Thomas Huth
2020-10-07  4:17 ` Launchpad Bug Tracker

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