Re: [PATCH v5 2/8] iommu: Remove IOMMU_DEV_FEAT_SVA

Linus Heckemann
2025-12-25T21:16:08Z

Lu Baolu <baolu.lu@linux.intel.com> writes:

> From: Jason Gunthorpe <jgg@nvidia.com>
>
> None of the drivers implement anything here anymore, remove the dead code.
>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> Reviewed-by: Kevin Tian <kevin.tian@intel.com>
> Reviewed-by: Yi Liu <yi.l.liu@intel.com>
> Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> ---
> drivers/accel/amdxdna/aie2_pci.c | 13 ++-----------
> drivers/dma/idxd/init.c | 8 +-------
> drivers/iommu/amd/iommu.c | 2 --
> drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 2 --
> drivers/iommu/intel/iommu.c | 6 ------
> drivers/iommu/iommu-sva.c | 3 ---
> drivers/misc/uacce/uacce.c | 9 ---------
> include/linux/iommu.h | 9 +--------
> 8 files changed, 4 insertions(+), 48 deletions(-)
>
> diff --git a/drivers/accel/amdxdna/aie2_pci.c b/drivers/accel/amdxdna/aie2_pci.c
> index 5a058e565b01..c6cf7068d23c 100644
> --- a/drivers/accel/amdxdna/aie2_pci.c
> +++ b/drivers/accel/amdxdna/aie2_pci.c
> @@ -512,12 +512,6 @@ static int aie2_init(struct amdxdna_dev *xdna)
> goto release_fw;
> }
>
> - ret = iommu_dev_enable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA);
> - if (ret) {
> - XDNA_ERR(xdna, "Enable PASID failed, ret %d", ret);
> - goto free_irq;
> - }
> -
> psp_conf.fw_size = fw->size;
> psp_conf.fw_buf = fw->data;
> for (i = 0; i < PSP_MAX_REGS; i++)
> @@ -526,14 +520,14 @@ static int aie2_init(struct amdxdna_dev *xdna)
> if (!ndev->psp_hdl) {
> XDNA_ERR(xdna, "failed to create psp");
> ret = -ENOMEM;
> - goto disable_sva;
> + goto free_irq;
> }
> xdna->dev_handle = ndev;
>
> ret = aie2_hw_start(xdna);
> if (ret) {
> XDNA_ERR(xdna, "start npu failed, ret %d", ret);
> - goto disable_sva;
> + goto free_irq;
> }
>
> ret = aie2_mgmt_fw_query(ndev);
> @@ -584,8 +578,6 @@ static int aie2_init(struct amdxdna_dev *xdna)
> aie2_error_async_events_free(ndev);
> stop_hw:
> aie2_hw_stop(xdna);
> -disable_sva:
> - iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA);
> free_irq:
> pci_free_irq_vectors(pdev);
> release_fw:
> @@ -601,7 +593,6 @@ static void aie2_fini(struct amdxdna_dev *xdna)
>
> aie2_hw_stop(xdna);
> aie2_error_async_events_free(ndev);
> - iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA);
> pci_free_irq_vectors(pdev);
> }
>
> diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
> index fca1d2924999..2d3d580b9987 100644
> --- a/drivers/dma/idxd/init.c
> +++ b/drivers/dma/idxd/init.c
> @@ -633,17 +633,11 @@ static int idxd_enable_sva(struct pci_dev *pdev)
> ret = iommu_dev_enable_feature(&pdev->dev, IOMMU_DEV_FEAT_IOPF);
> if (ret)
> return ret;
> -
> - ret = iommu_dev_enable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA);
> - if (ret)
> - iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_IOPF);
> -
> - return ret;
> + return 0;
> }
>
> static void idxd_disable_sva(struct pci_dev *pdev)
> {
> - iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_SVA);
> iommu_dev_disable_feature(&pdev->dev, IOMMU_DEV_FEAT_IOPF);
> }
>
> diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
> index dea0fed7abb0..17aab6d04a13 100644
> --- a/drivers/iommu/amd/iommu.c
> +++ b/drivers/iommu/amd/iommu.c
> @@ -2991,7 +2991,6 @@ static int amd_iommu_dev_enable_feature(struct device *dev,
>
> switch (feat) {
> case IOMMU_DEV_FEAT_IOPF:
> - case IOMMU_DEV_FEAT_SVA:
> break;
> default:
> ret = -EINVAL;
> @@ -3007,7 +3006,6 @@ static int amd_iommu_dev_disable_feature(struct device *dev,
>
> switch (feat) {
> case IOMMU_DEV_FEAT_IOPF:
> - case IOMMU_DEV_FEAT_SVA:
> break;
> default:
> ret = -EINVAL;
> diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> index 6cb875f98905..73f9885d20f1 100644
> --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> +++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
> @@ -3664,7 +3664,6 @@ static int arm_smmu_dev_enable_feature(struct device *dev,
>
> switch (feat) {
> case IOMMU_DEV_FEAT_IOPF:
> - case IOMMU_DEV_FEAT_SVA:
> return 0;
> default:
> return -EINVAL;
> @@ -3681,7 +3680,6 @@ static int arm_smmu_dev_disable_feature(struct device *dev,
>
> switch (feat) {
> case IOMMU_DEV_FEAT_IOPF:
> - case IOMMU_DEV_FEAT_SVA:
> return 0;
> default:
> return -EINVAL;
> diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
> index 857c431d8ec5..4c3be92804e2 100644
> --- a/drivers/iommu/intel/iommu.c
> +++ b/drivers/iommu/intel/iommu.c
> @@ -3956,9 +3956,6 @@ intel_iommu_dev_enable_feat(struct device *dev, enum iommu_dev_features feat)
> case IOMMU_DEV_FEAT_IOPF:
> return intel_iommu_enable_iopf(dev);
>
> - case IOMMU_DEV_FEAT_SVA:
> - return 0;
> -
> default:
> return -ENODEV;
> }
> @@ -3972,9 +3969,6 @@ intel_iommu_dev_disable_feat(struct device *dev, enum iommu_dev_features feat)
> intel_iommu_disable_iopf(dev);
> return 0;
>
> - case IOMMU_DEV_FEAT_SVA:
> - return 0;
> -
> default:
> return -ENODEV;
> }
> diff --git a/drivers/iommu/iommu-sva.c b/drivers/iommu/iommu-sva.c
> index ab18bc494eef..944daa0dabd6 100644
> --- a/drivers/iommu/iommu-sva.c
> +++ b/drivers/iommu/iommu-sva.c
> @@ -63,9 +63,6 @@ static struct iommu_mm_data *iommu_alloc_mm_data(struct mm_struct *mm, struct de
> * reference is taken. Caller must call iommu_sva_unbind_device()
> * to release each reference.
> *
> - * iommu_dev_enable_feature(dev, IOMMU_DEV_FEAT_SVA) must be called first, to
> - * initialize the required SVA features.
> - *
> * On error, returns an ERR_PTR value.
> */
> struct iommu_sva *iommu_sva_bind_device(struct device *dev, struct mm_struct *mm)
> diff --git a/drivers/misc/uacce/uacce.c b/drivers/misc/uacce/uacce.c
> index bdc2e6fda782..2a1db2abeeca 100644
> --- a/drivers/misc/uacce/uacce.c
> +++ b/drivers/misc/uacce/uacce.c
> @@ -479,14 +479,6 @@ static unsigned int uacce_enable_sva(struct device *parent, unsigned int flags)
> dev_err(parent, "failed to enable IOPF feature! ret = %pe\n", ERR_PTR(ret));
> return flags;
> }
> -
> - ret = iommu_dev_enable_feature(parent, IOMMU_DEV_FEAT_SVA);
> - if (ret) {
> - dev_err(parent, "failed to enable SVA feature! ret = %pe\n", ERR_PTR(ret));
> - iommu_dev_disable_feature(parent, IOMMU_DEV_FEAT_IOPF);
> - return flags;
> - }
> -
> return flags | UACCE_DEV_SVA;
> }
>
> @@ -495,7 +487,6 @@ static void uacce_disable_sva(struct uacce_device *uacce)
> if (!(uacce->flags & UACCE_DEV_SVA))
> return;
>
> - iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_SVA);
> iommu_dev_disable_feature(uacce->parent, IOMMU_DEV_FEAT_IOPF);
> }
>
> diff --git a/include/linux/iommu.h b/include/linux/iommu.h
> index 7e8c2af89799..bfdd2e71e124 100644
> --- a/include/linux/iommu.h
> +++ b/include/linux/iommu.h
> @@ -318,18 +318,11 @@ struct iommu_iort_rmr_data {
>
> /**
> * enum iommu_dev_features - Per device IOMMU features
> - * @IOMMU_DEV_FEAT_SVA: Shared Virtual Addresses
> - * @IOMMU_DEV_FEAT_IOPF: I/O Page Faults such as PRI or Stall. Generally
> - * enabling %IOMMU_DEV_FEAT_SVA requires
> - * %IOMMU_DEV_FEAT_IOPF, but some devices manage I/O Page
> - * Faults themselves instead of relying on the IOMMU. When
> - * supported, this feature must be enabled before and
> - * disabled after %IOMMU_DEV_FEAT_SVA.
> + * @IOMMU_DEV_FEAT_IOPF: I/O Page Faults such as PRI or Stall.
> *
> * Device drivers enable a feature using iommu_dev_enable_feature().
> */
> enum iommu_dev_features {
> - IOMMU_DEV_FEAT_SVA,
> IOMMU_DEV_FEAT_IOPF,
> };
>
> --
> 2.43.0

Hi all,

It appears the code removed here was not in fact entirely dead; my 2024
gpd win mini ("G1617-01", with a Ryzen 8840U) fails to suspend
correctly, and I bisected the issue to this commit.

dmesg:

[ 141.397168] wlp1s0: deauthenticating from 20:05:b6:ff:c4:5e by local choice (Reason: 3=DEAUTH_LEAVING)
[ 141.716327] PM: suspend entry (s2idle)
[ 141.783603] Filesystems sync: 0.067 seconds
[ 141.895439] Freezing user space processes
[ 141.896512] Freezing user space processes completed (elapsed 0.001 seconds)
[ 141.896515] OOM killer disabled.
[ 141.896516] Freezing remaining freezable tasks
[ 141.897523] Freezing remaining freezable tasks completed (elapsed 0.001 seconds)
[ 141.897527] printk: Suspending console(s) (use no_console_suspend to debug)
[ 142.292185] ACPI: EC: interrupt blocked
[ 149.879420] amd_pmc AMDI0009:00: Last suspend didn't reach deepest state
note ^
[ 150.026394] ACPI: EC: interrupt unblocked
[ 150.196340] [drm] PCIE GART of 512M enabled (table at 0x00000081FFD00000).
[ 150.196503] amdgpu 0000:c3:00.0: amdgpu: SMU is resuming...
[ 150.200585] amdgpu 0000:c3:00.0: amdgpu: SMU is resumed successfully!
[ 150.228549] nvme nvme0: 16/0/0 default/read/poll queues
[ 150.244609] nvme nvme0: Failed to get ANA log: 16649
[ 150.319610] amdgpu 0000:c3:00.0: amdgpu: ring gfx_0.0.0 uses VM inv eng 0 on hub 0
[ 150.319619] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.0.0 uses VM inv eng 1 on hub 0
[ 150.319621] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.1.0 uses VM inv eng 4 on hub 0
[ 150.319623] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.2.0 uses VM inv eng 6 on hub 0
[ 150.319624] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.3.0 uses VM inv eng 7 on hub 0
[ 150.319625] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.0.1 uses VM inv eng 8 on hub 0
[ 150.319627] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.1.1 uses VM inv eng 9 on hub 0
[ 150.319628] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.2.1 uses VM inv eng 10 on hub 0
[ 150.319629] amdgpu 0000:c3:00.0: amdgpu: ring comp_1.3.1 uses VM inv eng 11 on hub 0
[ 150.319630] amdgpu 0000:c3:00.0: amdgpu: ring sdma0 uses VM inv eng 12 on hub 0
[ 150.319632] amdgpu 0000:c3:00.0: amdgpu: ring vcn_unified_0 uses VM inv eng 0 on hub 8
[ 150.319633] amdgpu 0000:c3:00.0: amdgpu: ring jpeg_dec uses VM inv eng 1 on hub 8
[ 150.319635] amdgpu 0000:c3:00.0: amdgpu: ring mes_kiq_3.1.0 uses VM inv eng 13 on hub 0
[ 150.329858] [drm] ring gfx_32773.1.1 was added
[ 150.330624] [drm] ring compute_32773.2.2 was added
[ 150.331491] [drm] ring sdma_32773.3.3 was added
[ 150.331565] [drm] ring gfx_32773.1.1 ib test pass
[ 150.331603] [drm] ring compute_32773.2.2 ib test pass
[ 150.331699] [drm] ring sdma_32773.3.3 ib test pass
[ 150.498226] usb 1-3: reset full-speed USB device number 2 using xhci_hcd
[ 150.738138] usb 1-5: reset full-speed USB device number 4 using xhci_hcd
[ 150.906575] OOM killer enabled.
[ 150.906578] Restarting tasks ...
[ 150.906640] input: Microsoft X-Box 360 pad as /devices/pci0000:00/0000:00:08.1/0000:c3:00.3/usb1/1-5/1-5:1.0/input/input27
[ 150.907291] done.
[ 150.907372] random: crng reseeded on system resumption
[ 150.931675] PM: suspend exit

Let me know if there's any further information that would be helpful here.

Linus