[PATCH V6 8/8] vfio: platform: check reset call return code during release

From: Sinan Kaya
Date: Sat May 28 2016 - 18:01:54 EST


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@xxxxxxxxxxxxxx>
---
drivers/vfio/platform/vfio_platform_common.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 962cfb1..bb05ca0 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -243,7 +243,15 @@ 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);
}
--
1.8.2.1