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Date: Tue, 26 Dec 2023 10:30:04 +0800
From: Wu Zongyong <wuzongyong@linux.alibaba.com>
To: alex.williamson@redhat.com
Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	wutu.xq2@linux.alibaba.com
Subject: [Question] Is it must for vfio-mdev parent driver to implement a
 pci-compliant configuration r/w interface
Message-ID: <ZYo6rITis9siz2Av@wuzongyong-alibaba>
Reply-To: Wu Zongyong <wuzongyong@linux.alibaba.com>
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Hi,

For vfio, I know there are two method to get region size:
  1. VFIO_DEVICE_GET_REGION_INFO ioctl
  2. write a value of all 1's to the bar register of vfio-device fd
    and then read the value back which is described in pci spec

Now I am curious about is it a must for a vfio-mdev parent driver to
implement the method 2? Or it is just a optional interface.

Thanks,
Wu Zongyong