Re: [PATCH v5 1/4] iommu: Add page_ext for IOMMU_DEBUG_PAGEALLOC

[Pranjal Shrivastava]

On Tue, Jan 06, 2026 at 04:21:57PM +0000, Mostafa Saleh wrote:
> Add a new config IOMMU_DEBUG_PAGEALLOC, which registers new data to
> page_ext.
> 
> This config will be used by the IOMMU API to track pages mapped in
> the IOMMU to catch drivers trying to free kernel memory that they
> still map in their domains, causing all types of memory corruption.
> 
> This behaviour is disabled by default and can be enabled using
> kernel cmdline iommu.debug_pagealloc.
> 
> Reviewed-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Signed-off-by: Mostafa Saleh <smostafa@xxxxxxxxxx>
> ---
>  .../admin-guide/kernel-parameters.txt         |  9 ++++++
>  drivers/iommu/Kconfig                         | 19 +++++++++++
>  drivers/iommu/Makefile                        |  1 +
>  drivers/iommu/iommu-debug-pagealloc.c         | 32 +++++++++++++++++++
>  include/linux/iommu-debug-pagealloc.h         | 17 ++++++++++
>  mm/page_ext.c                                 |  4 +++
>  6 files changed, 82 insertions(+)
>  create mode 100644 drivers/iommu/iommu-debug-pagealloc.c
>  create mode 100644 include/linux/iommu-debug-pagealloc.h
> 

Reviewed-by: Pranjal Shrivastava <praan@xxxxxxxxxx>
Thanks!