Re: [PATCH v8 07/10] iommufd: Fault-capable hwpt attach/detach/replace

[Baolu Lu <baolu.lu@linux.intel.com>]

On 2024/10/28 17:56, Zhangfei Gao wrote:
> On Sun, 27 Oct 2024 at 22:26, Baolu Lu <baolu.lu@linux.intel.com> wrote:
> 
>>
>> Can you please make this change a formal patch by yourself? As I don't
>> have hardware in hand, I'm not confident to accurately describe the
>> requirement or verify the new version during the upstream process.
>>
> 
> OK, how about this one
> 
> Subject: [PATCH] iommufd: modify iommufd_fault_iopf_enable limitation
> 
> iommufd_fault_iopf_enable has limitation to PRI on PCI/SRIOV VFs
> because the PRI might be a shared resource and current iommu
> subsystem is not ready to support enabling/disabling PRI on a VF
> without any impact on others.
> 
> However, we have devices that appear as PCI but are actually on the
> AMBA bus. These fake PCI devices have PASID capability, support
> stall as well as SRIOV, so remove the limitation for these devices.
> 
> Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> ---
>   drivers/iommu/iommufd/fault.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iommu/iommufd/fault.c b/drivers/iommu/iommufd/fault.c
> index bca956d496bd..8b3e34250dae 100644
> --- a/drivers/iommu/iommufd/fault.c
> +++ b/drivers/iommu/iommufd/fault.c
> @@ -10,6 +10,7 @@
>   #include <linux/module.h>
>   #include <linux/mutex.h>
>   #include <linux/pci.h>
> +#include <linux/pci-ats.h>
>   #include <linux/poll.h>
>   #include <uapi/linux/iommufd.h>
> 
> @@ -27,8 +28,12 @@ static int iommufd_fault_iopf_enable(struct
> iommufd_device *idev)
>           * resource between PF and VFs. There is no coordination for this
>           * shared capability. This waits for a vPRI reset to recover.
>           */
> -       if (dev_is_pci(dev) && to_pci_dev(dev)->is_virtfn)
> -               return -EINVAL;
> +       if (dev_is_pci(dev)) {
> +               struct pci_dev *pdev = to_pci_dev(dev);
> +
> +               if (pdev->is_virtfn && pci_pri_supported(pdev))
> +                       return -EINVAL;
> +       }
> 
>          mutex_lock(&idev->iopf_lock);
>          /* Device iopf has already been on. */

Looks fine to me, but you need to use the "git sendemail" command to
post the patch. Otherwise, the maintainer has no means to pick your
patch with tools like b4.