vfio: platform: check reset call return code during release

Release call is ignoring the return code from reset call and can
potentially continue even though reset call failed.

If reset_required module parameter is set, this patch is going
to validate the return code and will cause stack dump with
WARN_ON and warn the user of failure.

Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 389d651..1cf2d46 100644 (file)
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -230,7 +230,15 @@ static void vfio_platform_release(void *device_data)
        mutex_lock(&driver_lock);
 
        if (!(--vdev->refcnt)) {
-               vfio_platform_call_reset(vdev, NULL);
+               const char *extra_dbg = NULL;
+               int ret;
+
+               ret = vfio_platform_call_reset(vdev, &extra_dbg);
+               if (ret && vdev->reset_required) {
+                       dev_warn(vdev->device, "reset driver is required and reset call failed in release (%d) %s\n",
+                                ret, extra_dbg ? extra_dbg : "");
+                       WARN_ON(1);
+               }
                vfio_platform_regions_cleanup(vdev);
                vfio_platform_irq_cleanup(vdev);
        }