cpr-transfer will use the device name as a key to find the value
of the device descriptor in new QEMU. However, if the descriptor
number is specified by a command-line fd parameter, then
vfio_device_get_name creates a name that includes the fd number.
This causes a chicken-and-egg problem: new QEMU must know the fd
number to construct a name to find the fd number.
To fix, create an invariant name based on the id command-line
parameter. If id is not defined, add a CPR blocker.
Signed-off-by: Steve Sistare <steven.sist...@oracle.com>
---
hw/vfio/helpers.c | 18 +++++++++++++++---
hw/vfio/iommufd.c | 2 ++
include/hw/vfio/vfio-common.h | 1 +
3 files changed, 18 insertions(+), 3 deletions(-)
diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c
index 913796f..bd94b86 100644
--- a/hw/vfio/helpers.c
+++ b/hw/vfio/helpers.c
@@ -25,6 +25,8 @@
#include "hw/vfio/vfio-common.h"
#include "hw/hw.h"
#include "trace.h"
+#include "migration/blocker.h"
+#include "migration/cpr.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "qemu/units.h"
@@ -636,6 +638,7 @@ bool vfio_device_get_name(VFIODevice *vbasedev, Error
**errp)
{
ERRP_GUARD();
struct stat st;
+ bool ret = true;
if (vbasedev->fd < 0) {
if (stat(vbasedev->sysfsdev, &st) < 0) {
@@ -653,15 +656,24 @@ bool vfio_device_get_name(VFIODevice *vbasedev, Error
**errp)
return false;
}
/*
- * Give a name with fd so any function printing out vbasedev->name
+ * Give a name so any function printing out vbasedev->name
* will not break.
*/
if (!vbasedev->name) {
- vbasedev->name = g_strdup_printf("VFIO_FD%d", vbasedev->fd);
+ if (vbasedev->dev->id) {
+ vbasedev->name = g_strdup(vbasedev->dev->id);
+ } else {
+ vbasedev->name = g_strdup_printf("VFIO_FD%d", vbasedev->fd);
+ error_setg(&vbasedev->cpr_id_blocker,
+ "vfio device with fd=%d needs an id property",
+ vbasedev->fd);
+ ret = migrate_add_blocker_modes(&vbasedev->cpr_id_blocker,
errp,
+ MIG_MODE_CPR_TRANSFER, -1) ==
0;
+ }
}
}
- return true;
+ return ret;
}
void vfio_device_set_fd(VFIODevice *vbasedev, const char *str, Error **errp)
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index 2f888e5..8308715 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -24,6 +24,7 @@
#include "system/reset.h"
#include "qemu/cutils.h"
#include "qemu/chardev_open.h"
+#include "migration/blocker.h"
#include "pci.h"
#include "exec/ram_addr.h"
@@ -657,6 +658,7 @@ static void iommufd_cdev_detach(VFIODevice *vbasedev)
iommufd_cdev_container_destroy(container);
vfio_put_address_space(space);
+ migrate_del_blocker(&vbasedev->cpr_id_blocker);
iommufd_cdev_unbind_and_disconnect(vbasedev);
close(vbasedev->fd);
}
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index ca10abc..37e7c26 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -147,6 +147,7 @@ typedef struct VFIODevice {
VFIOMigration *migration;
Error *migration_blocker;
Error *cpr_mdev_blocker;
+ Error *cpr_id_blocker;
OnOffAuto pre_copy_dirty_page_tracking;
OnOffAuto device_dirty_page_tracking;
bool dirty_pages_supported;
--
1.8.3.1
