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SubjectRE: [PATCH V4 07/11] vfio/pci: Update stale comment
Date
> From: Chatre, Reinette <reinette.chatre@intel.com>
> Sent: Friday, April 28, 2023 1:36 AM
>
> @@ -419,11 +419,9 @@ static int vfio_msi_set_vector_signal(struct
> vfio_pci_core_device *vdev,
> }
>
> /*
> - * The MSIx vector table resides in device memory which may be
> cleared
> - * via backdoor resets. We don't allow direct access to the vector
> - * table so even if a userspace driver attempts to save/restore
> around
> - * such a reset it would be unsuccessful. To avoid this, restore the
> - * cached value of the message prior to enabling.
> + * If the vector was previously allocated, refresh the on-device
> + * message data before enabling in case it had been cleared or
> + * corrupted since writing.
> */
> cmd = vfio_pci_memory_lock_and_enable(vdev);
> if (msix) {

What about keeping backdoor reset as an example, e.g.

"in case it had been cleared or corrupted (e.g. due to backdoor resets) ..."

otherwise one may doubt whether it is a more severe problem causing
the corruption inadvertently w/o userspace driver's awareness and then
whether just restoring the data is sufficient to move on.

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