the vfio_pci_hot_reset differentiate the single and multi in-used
devices for reset. but in multi case, when some dependent devices
are not assigned to VM, the devices can not be recovered by driver.
Signed-off-by: Chen Fan <chen.fan.f...@cn.fujitsu.com>
---
hw/vfio/pci.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 7cc81ae..aeb489e 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3311,6 +3311,7 @@ static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool
single)
PCIHostDeviceAddress host;
VFIOPCIDevice *tmp;
VFIODevice *vbasedev_iter;
+ bool found;
host.domain = devices[i].segment;
host.bus = devices[i].bus;
@@ -3340,6 +3341,7 @@ static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool
single)
goto out;
}
+ found = false;
/* Prep dependent devices for reset and clear our marker. */
QLIST_FOREACH(vbasedev_iter, &group->device_list, next) {
if (vbasedev_iter->type != VFIO_DEVICE_TYPE_PCI) {
@@ -3351,12 +3353,23 @@ static int vfio_pci_hot_reset(VFIOPCIDevice *vdev, bool
single)
ret = -EINVAL;
goto out_single;
}
+ found = true;
vfio_pci_pre_reset(tmp);
tmp->vbasedev.needs_reset = false;
multi = true;
break;
}
}
+
+ /*
+ * If the dependent device is not assigned to VM, we should
+ * not call hot bus reset, otherwise, the dependent device
+ * can not be used in the future.
+ */
+ if (!single && !found) {
+ ret = -EINVAL;
+ goto out_single;
+ }
}
if (!single && !multi) {
--
1.9.3
