Re: [PATCH v5 23/24] iommu/amd: Assign per-vIOMMU translate device ID

From: Suthikulpanit, Suravee

Date: Mon Sep 28 2026 - 06:24:49 EST




On 9/22/2026 2:09 PM, Guixin Liu wrote:
@@ -93,31 +98,63 @@ int amd_iommufd_viommu_init(struct iommufd_viommu *viommu, struct iommu_domain *
data.out_vfmmio_mmap_offset = aviommu->vfmmio_mmap_offset;
- /* Reset vIOMMU MMIOs to initialize the vIOMMU */
+ /* Reset vIOMMU MMIOs before the trans_devid is visible in the pool. */
ret = amd_iommu_reset_vmmio(iommu, aviommu->gid);
if (ret)
- goto err_init;
+ goto err_trans_devid;
+
+ mutex_lock(&aviommu->trans_devid_lock);
+ ret = amd_iommu_trans_devid_alloc(iommu->pci_seg, aviommu);
+ if (ret < 0) {
+ mutex_unlock(&aviommu->trans_devid_lock);
+ goto err_trans_devid;
+ }
+ trans_devid_allocated = true;
+ aviommu->trans_devid = ret;
+
+ ret = amd_iommu_set_translate_dte(viommu);
+ if (ret)
+ goto err_init_unlock;
+ trans_dte_set = true;
+ amd_iommu_update_vfctrl_mmio_translate_devid(iommu, aviommu->gid,
+ aviommu->trans_devid);
+ mutex_unlock(&aviommu->trans_devid_lock);
ret = amd_viommu_init_one(iommu, aviommu);
if (ret)
goto err_init;
+ uninit_on_err = true;
ret = iommu_copy_struct_to_user(user_data, &data,
IOMMU_VIOMMU_TYPE_AMD,
out_vfmmio_mmap_offset);
if (ret)
- goto err_init_one;
+ goto err_init;
viommu->ops = &amd_viommu_ops;
- spin_lock_irqsave(&pdom->lock, flags);
- list_add(&aviommu->pdom_list, &pdom->viommu_list);
- spin_unlock_irqrestore(&pdom->lock, flags);
-
return 0;
-err_init_one:
- amd_viommu_uninit_one(iommu, aviommu);
err_init:
+ mutex_lock(&aviommu->trans_devid_lock);
+err_init_unlock:
+ if (trans_dte_set) {
+ spin_lock_irqsave(&pdom->lock, flags);
+ if (!list_empty(&aviommu->pdom_list))
+ list_del_init(&aviommu->pdom_list);
+ spin_unlock_irqrestore(&pdom->lock, flags);
+ amd_iommu_update_vfctrl_mmio_translate_devid(iommu, aviommu->gid, 0);
+ amd_iommu_clear_translate_dte(iommu, aviommu->trans_dev_data,
+ aviommu->trans_devid);
+ amd_iommu_free_dev_data(iommu, aviommu->trans_dev_data);
+ aviommu->trans_dev_data = NULL;
+ }
+ if (trans_devid_allocated)
+ amd_iommu_trans_devid_free(iommu->pci_seg, aviommu->trans_devid,
+ aviommu);
+ mutex_unlock(&aviommu->trans_devid_lock);
+ if (uninit_on_err)
+ amd_viommu_uninit_one(iommu, aviommu);
+err_trans_devid:
iommufd_viommu_destroy_mmap(&aviommu->core, aviommu->vfmmio_mmap_offset);
err_mmap:
amd_iommu_gid_free(iommu, aviommu->gid);
@@ -140,6 +177,17 @@ static void amd_iommufd_viommu_destroy(struct iommufd_viommu *viommu)
spin_unlock_irqrestore(&pdom->lock, flags);
xa_destroy(&aviommu->gdomid_array);
iommufd_viommu_destroy_mmap(&aviommu->core, aviommu->vfmmio_mmap_offset);
+
+ mutex_lock(&aviommu->trans_devid_lock);
+ amd_iommu_update_vfctrl_mmio_translate_devid(iommu, aviommu->gid, 0);
+ amd_iommu_clear_translate_dte(iommu, aviommu->trans_dev_data,
+ aviommu->trans_devid);
+ amd_iommu_free_dev_data(iommu, aviommu->trans_dev_data);
+ aviommu->trans_dev_data = NULL;
+ amd_iommu_trans_devid_free(iommu->pci_seg, aviommu->trans_devid,
+ aviommu);
+ mutex_unlock(&aviommu->trans_devid_lock);
+
amd_viommu_uninit_one(iommu, aviommu);
amd_iommu_gid_free(iommu, aviommu->gid);
mutex_destroy(&aviommu->vfctrl_lock);
Should destroy trans_devid_lock too.

Correct. I'll update in v6.

Thanks,
Suravee