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Message-ID: <fe018236-35b5-3bc1-6984-fca9537e47c7@linux.microsoft.com>
Date:   Wed, 2 Mar 2022 10:13:34 -0800
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Subject: Re: [PATCH v3 26/30] drivers: hv: dxgkrnl: Offer and reclaim
 allocations
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To:     Wei Liu <wei.liu@kernel.org>
Cc:     kys@microsoft.com, haiyangz@microsoft.com, sthemmin@microsoft.com,
        linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org,
        spronovo@microsoft.com, spronovo@linux.microsoft.com,
        gregkh@linuxfoundation.org
References: <719fe06b7cbe9ac12fa4a729e810e3383ab421c1.1646163378.git.iourit@linux.microsoft.com>
 <3a6779567438b02566012679f01ebb065e3761db.1646163379.git.iourit@linux.microsoft.com>
 <20220302142517.kgc5o7ufj2yf4cif@liuwe-devbox-debian-v2>
From:   Iouri Tarassov <iourit@linux.microsoft.com>
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On 3/2/2022 6:25 AM, Wei Liu wrote:
> On Tue, Mar 01, 2022 at 11:46:13AM -0800, Iouri Tarassov wrote:
> > Implement ioctls to offer and reclaim compute device allocations:
> >   - LX_DXOFFERALLOCATIONS,
> >   - LX_DXRECLAIMALLOCATIONS2
> > 
> > When a user mode driver (UMD) does not need to access an allocation,
>
> What is a "user mode driver" in this context? Is that something that
> runs inside the guest?

Hi Wei,

The user mode driver runs inside the guest. This driver is written by
hardware vendors.
For example, the NVIDIA's Cuda runtime is considered a user mode driver.
The driver
provides a specific API to applications (like the Cuda API).

The cover letter explains the design of the virtual compute device
paravirtualization
model and describes all components, which are involved. I feel that I do
not need to
include explanation to every patch.

Thanks
Iouri