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Date: Thu, 7 Dec 2017 19:18:44 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
Message-ID: <20171207191726-musend-email-mst@kernel.org>
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Subject: [Qemu-devel] question on virtio ccw
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To: Cornelia Huck <cohuck@redhat.com>
Cc: qemu-devel@nongnu.org

I see this in ccw in qemu:

            if (virtio_set_status(vdev, status) == 0) {
                if (vdev->status == 0) {
                    virtio_ccw_reset_virtio(dev, vdev);
                }
                if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
                    virtio_ccw_start_ioeventfd(dev);
                }
                sch->curr_status.scsw.count = ccw.count - sizeof(status);
                ret = 0;
            } else {
                /* Trigger a command reject. */
                ret = -ENOSYS;
            }

virtio_set_status on success sets vdev->status to status.
Why check vdev->status in one place and status in another?

-- 
MST