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Date:   Wed, 4 May 2022 19:23:07 +0200
From:   Pavel Machek <pavel@ucw.cz>
To:     Michael Kelley <mikelley@microsoft.com>
Cc:     kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        wei.liu@kernel.org, linux-kernel@vger.kernel.org,
        linux-hyperv@vger.kernel.org, vkuznets@redhat.com,
        decui@microsoft.com, drawat.floss@gmail.com, airlied@linux.ie,
        daniel@ffwll.ch, jejb@linux.ibm.com, martin.petersen@oracle.com,
        deller@gmx.de, dri-devel@lists.freedesktop.org,
        linux-scsi@vger.kernel.org, linux-fbdev@vger.kernel.org
Subject: Re: [PATCH 0/4] Remove support for Hyper-V 2008 and 2008R2/Win7
Message-ID: <20220504172307.GB1623@bug>
References: <1651509391-2058-1-git-send-email-mikelley@microsoft.com>
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Hi!

> Linux code for running as a Hyper-V guest includes special cases for the
> first released versions of Hyper-V: 2008 and 2008R2/Windows 7. These
> versions were very thinly used for running Linux guests when first
> released more than 12 years ago, and they are now out of support
> (except for extended security updates). As initial versions, they
> lack the performance features needed for effective production usage
> of Linux guests. In total, there's no need to continue to support
> the latest Linux kernels on these versions of Hyper-V.
> 
> Simplify the code for running on Hyper-V by removing the special
> cases. This includes removing the negotiation of the VMbus protocol
> versions for 2008 and 2008R2, and the special case code based on
> those VMbus protocol versions. Changes are in the core VMbus code and
> several drivers for synthetic VMbus devices.

> 2008 and 2008R2, so if the broader Linux kernel community surfaces
> a reason why this clean-up should not be done now, we can wait.
> But I think we want to eventually stop carrying around this extra
> baggage, and based on discussions with the Hyper-V team within
> Microsoft, we're already past the point that it has any value.

Normal way to do such deprecations is to put printks in first, then hide it
under config option noone sets, and wait for year or so if anyone complains.

We can't really remove code that is in use.

Best regards,
									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html