Re: [RFC PATCH 1/4] drivers/iommu: Add page_ext for IOMMU_DEBUG_PAGEALLOC

[Jörg Rödel]

On Fri, Oct 03, 2025 at 05:32:26PM +0000, Mostafa Saleh wrote:
> +config IOMMU_DEBUG_PAGEALLOC
> +	bool "Debug page memory allocations against IOMMU"
> +	depends on DEBUG_PAGEALLOC && IOMMU_API && PAGE_EXTENSION
> +	help
> +		This config checks when a page is freed by the kernel
> +		it's not mapped in any IOMMU domain. It can help with
> +		debugging use-after-free from driver doing DMA.
> +		This santaizer can have false-negative cases where some
> +		problems won't be detected.
> +		Expect overhead when enabling this + enabling the kernel
> +		command line iommu.debug_pagealloc.
> +
> +		If unsure, say N here.

Expected indentation here is <tab><space><space> and not <tab><tab>.

> --- /dev/null
> +++ b/drivers/iommu/iommu-debug.c

Is there a plan for this file to contain more than page-alloc debugging? If
not, it should get a more specific name, like iommu-debug-pagealloc.c or
similar.