RE: [PATCH v4 02/11] iommu/vt-d: Remove clearing translation data in disable_dmar_iommu()

Tian, Kevin
2022-07-07T03:03:58Z

> From: Lu Baolu <baolu.lu@linux.intel.com>
> Sent: Wednesday, July 6, 2022 10:55 AM
>
> The disable_dmar_iommu() is called when IOMMU initialization fails or
> the IOMMU is hot-removed from the system. In both cases, there is no
> need to clear the IOMMU translation data structures for devices.
>
> On the initialization path, the device probing only happens after the
> IOMMU is initialized successfully, hence there're no translation data
> structures.
>
> On the hot-remove path, there is no real use case where the IOMMU is
> hot-removed, but the devices that it manages are still alive in the
> system. The translation data structures were torn down during device
> release, hence there's no need to repeat it in IOMMU hot-remove path
> either. This removes the unnecessary code and only leaves a check.
>
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>