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Subject: Re: [PATCH 1/2] VMware detection support for x86 and x86-64
From: Zachary Amsden <zach@vmware.com>
To: "H. Peter Anvin" <hpa@zytor.com>
Cc: Alok Kataria <akataria@vmware.com>, Alok kataria <alokkataria1@gmail.com>,
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Date: Thu, 25 Sep 2008 15:20:54 -0700
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On Thu, 2008-09-25 at 14:59 -0700, H. Peter Anvin wrote:

> However, it is the particular use of this for detection use that is
> utterly damning.  Using random I/O port probes for hardware detect
> should have disappeared in the early 1990's, and it's really disturbing
> that virtualization vendors -- not just VMWare -- are, in effect,
> re-making all the mistakes hardware vendors did in the 1980's.

It's not disturbing, it's expected.  Re-using old broken solutions happens all the time, they can be perfectly valid in some contexts.  The problem is that they tend to live on and evolve into a larger context where they break again.  Surely we can do better, but how to do that isn't always clear-cut.  DMI is a pretty good standard for this, but it still doesn't solve the problem in all contexts (userspace apps).

Zach