On 05/08/2018 02:25 PM, Tony Krowiak wrote:
Introduces a VFIO based AP device. The device is defined via
the QEMU command line by specifying:
-device vfio-ap,sysfsdev=<path-to-mediated-matrix-device>
There may be only one vfio-ap device configured for a guest.
The mediated matrix device is created by the VFIO AP device
[..]
+ * directory.
+ */
+
+#include <linux/vfio.h>
+#include <sys/ioctl.h>
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/sysbus.h"
+#include "hw/vfio/vfio.h"
+#include "hw/vfio/vfio-common.h"
+#include "hw/s390x/ap-device.h"
+#include "qemu/error-report.h"
+#include "qemu/queue.h"
+#include "qemu/option.h"
+#include "qemu/config-file.h"
+#include "cpu.h"
+#include "kvm_s390x.h"
+#include "sysemu/sysemu.h"
+
+#define VFIO_AP_DEVICE_TYPE "vfio-ap"
+
+typedef struct VFIOAPDevice {
+ APDevice apdev;
+ VFIODevice vdev;
+ QTAILQ_ENTRY(VFIOAPDevice) sibling;
+} VFIOAPDevice;
+
+VFIOAPDevice *vfio_apdev;
+
+static void vfio_ap_compute_needs_reset(VFIODevice *vdev)
+{
+ vdev->needs_reset = false;
+}
+
+/*
+ * We don't need vfio_hot_reset_multi and vfio_eoi operations for
+ * vfio-ap-matrix device now.
+ */
+struct VFIODeviceOps vfio_ap_ops = {
+ .vfio_compute_needs_reset = vfio_ap_compute_needs_reset,
+};
+
I'm not familiar with the vfio infrastructure, but AFAIR I
haven't seen any substantial reset handling (QEMU or kernel).
Did I miss something?
If I did not. I think this is a big problem. We need to at least
zeroize the queues (e.g. on system reset) to avoid leaking
sensitive information. Without this, there is no sane way to use
ap-passthrough. Or am I wrong?
Regards,
Halil
