[PATCH v5 5/5] hisi_acc_vfio_pci: bugfix live migration function without VF device driver

Longfang Liu
2025-03-13T07:22:52Z

If the VF device driver is not loaded in the Guest OS and we attempt to
perform device data migration, the address of the migrated data will
be NULL.
The live migration recovery operation on the destination side will
access a null address value, which will cause access errors.

Therefore, live migration of VMs without added VF device drivers
does not require device data migration.
In addition, when the queue address data obtained by the destination
is empty, device queue recovery processing will not be performed.

Fixes: b0eed085903e ("hisi_acc_vfio_pci: Add support for VFIO live migration")
Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
.../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 25 +++++++++++++------
1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index cadc82419dca..44fa2d16bbcc 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -426,13 +426,6 @@ static int vf_qm_check_match(struct hisi_acc_vf_core_device *hisi_acc_vdev,
return -EINVAL;
}

- ret = qm_write_regs(vf_qm, QM_VF_STATE, &vf_data->vf_qm_state, 1);
- if (ret) {
- dev_err(dev, "failed to write QM_VF_STATE\n");
- return ret;
- }
-
- hisi_acc_vdev->vf_qm_state = vf_data->vf_qm_state;
hisi_acc_vdev->match_done = true;
return 0;
}
@@ -498,6 +491,13 @@ static int vf_qm_load_data(struct hisi_acc_vf_core_device *hisi_acc_vdev,
if (migf->total_length < sizeof(struct acc_vf_data))
return -EINVAL;

+ ret = qm_write_regs(qm, QM_VF_STATE, &vf_data->vf_qm_state, 1);
+ if (ret) {
+ dev_err(dev, "failed to write QM_VF_STATE\n");
+ return -EINVAL;
+ }
+ hisi_acc_vdev->vf_qm_state = vf_data->vf_qm_state;
+
qm->eqe_dma = vf_data->eqe_dma;
qm->aeqe_dma = vf_data->aeqe_dma;
qm->sqc_dma = vf_data->sqc_dma;
@@ -506,6 +506,12 @@ static int vf_qm_load_data(struct hisi_acc_vf_core_device *hisi_acc_vdev,
qm->qp_base = vf_data->qp_base;
qm->qp_num = vf_data->qp_num;

+ if (!vf_data->eqe_dma || !vf_data->aeqe_dma ||
+ !vf_data->sqc_dma || !vf_data->cqc_dma) {
+ dev_err(dev, "resume dma addr is NULL!\n");
+ return -EINVAL;
+ }
+
ret = qm_set_regs(qm, vf_data);
if (ret) {
dev_err(dev, "set VF regs failed\n");
@@ -726,8 +732,12 @@ static int hisi_acc_vf_load_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
{
struct device *dev = &hisi_acc_vdev->vf_dev->dev;
struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->resuming_migf;
+ struct acc_vf_data *vf_data = &migf->vf_data;
int ret;

+ if (vf_data->vf_qm_state != QM_READY)
+ return 0;
+
/* Recover data to VF */
ret = vf_qm_load_data(hisi_acc_vdev, migf);
if (ret) {
@@ -1531,6 +1541,7 @@ static int hisi_acc_vfio_pci_migrn_init_dev(struct vfio_device *core_vdev)
hisi_acc_vdev->vf_id = pci_iov_vf_id(pdev) + 1;
hisi_acc_vdev->pf_qm = pf_qm;
hisi_acc_vdev->vf_dev = pdev;
+ hisi_acc_vdev->vf_qm_state = QM_NOT_READY;
mutex_init(&hisi_acc_vdev->state_mutex);
mutex_init(&hisi_acc_vdev->open_mutex);

--
2.24.0