Re: [PATCH v3 2/5] iommu/amd: Fix DTE clearing and rename iommu_ignore_device()

> [ ... 52 lines skipped ... ]
> +/*
> + * Invalidate a DTE by clearing the Valid bit first.
> + * Note: Lockless; Not to be used on a fully probed
> + * device with live dev_data.
> + */
> +static void amd_iommu_disable_dte(struct dev_table_entry *ptr)
> +{
> +	struct dev_table_entry new = {};
> +
> +	write_dte_lower128(ptr, &new);
> +	write_dte_upper128(ptr, &new);
> +}

No need just call update_dte256() with a 0'd new. This is how all the
update flows work, and it flushes the DTE which this looks like it has
been missing all long.

-- 
Jason