[PATCH v2 09/11] vfio/migration: Reset device if setting recover state fails

[Avihai Horon]

If vfio_migration_set_state() fails to set the device in the requested
state it tries to put it in a recover state. If setting the device in
the recover state fails as well, hw_error is triggered and the VM is
aborted.

To improve user experience and avoid VM data loss, reset the device with
VFIO_RESET_DEVICE instead of aborting the VM.

Signed-off-by: Avihai Horon <avihaih@nvidia.com>
---
 hw/vfio/migration.c | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
index 852759e6ca..6c34502611 100644
--- a/hw/vfio/migration.c
+++ b/hw/vfio/migration.c
@@ -89,8 +89,16 @@ static int vfio_migration_set_state(VFIODevice *vbasedev,
         /* Try to put the device in some good state */
         mig_state->device_state = recover_state;
         if (ioctl(vbasedev->fd, VFIO_DEVICE_FEATURE, feature)) {
-            hw_error("%s: Device in error state, can't recover",
-                     vbasedev->name);
+            if (ioctl(vbasedev->fd, VFIO_DEVICE_RESET)) {
+                hw_error("%s: Device in error state, can't recover",
+                         vbasedev->name);
+            }
+
+            error_report(
+                "%s: Device was reset due to failure in changing device state 
to recover state %s",
+                vbasedev->name, mig_state_to_str(recover_state));
+
+            return -1;
         }
 
         error_report("%s: Failed changing device state to %s", vbasedev->name,
-- 
2.21.3