Re: [PATCH 00/22] media: iris: Restrict lower IOVA range for Venus and Iris VPUs

[Dmitry Baryshkov]

On Fri, Aug 07, 2026 at 01:54:44PM +0530, Vikash Garodia wrote:
> Qualcomm venus and iris VPUs reserve IOVA addresses below 0x25800000 
> (600MB) for non-pixel stream ID in secure mode. When the kernel 
> allocates DMA mappings from this restricted range, the VPU generate 
> unhandled SMMU page faults, leading to video failures and, in some 
> cases, spontaneous system reboots.
>  
> The issue is readily reproducible on affected platforms by running
> multiple concurrent video decode workloads, such as opening several
> browser tabs containing video streams.
> 
> To prevent allocations in the restricted region, this series introduces
> support for an IOMMU IOVA reserve memory-region in the Venus and Iris
> bindings and updates all affected device trees to reserve the low IOVA
> range [0, 0x25800000]. The memory-region is referenced by the video codec
> node, allowing the IOMMU layer to keep DMA allocations above the reserved
> boundary.
>  
> The series consists of:
>  
>   * Binding updates for Venus and Iris schemas to permit an additional
>     memory-region phandle describing the IOVA reservation.
>   * DTS updates for all affected Venus platforms.
>   * DTS updates for all affected Iris platforms.
>  
> This ensures that DMA allocations do not overlap restricted IOVA
> mappings for non-pixel stream IDs and prevents the resulting SMMU
> faults.

Some of these patches have been sent already. Why is it again at v1?

> 
> Signed-off-by: Vikash Garodia <vikash.garodia@xxxxxxxxxxxxxxxx>
> ---
> Daniel J Blueman (2):
>       dt-bindings: media: qcom,sm8550-iris: Allow IOVA reservation memory-region
>       arm64: dts: qcom: hamoa: Reserve low IOVA range for Iris
> 
> Vikash Garodia (20):
>       dt-bindings: media: qcom,venus-common: Allow IOVA reservation memory-region
>       dt-bindings: media: qcom,sc7180-venus: Allow IOVA reservation memory-region
>       arm64: dts: qcom: lemans: Reserve low IOVA range for Iris
>       arm64: dts: qcom: monaco: Reserve low IOVA range for Iris
>       arm64: dts: qcom: sc8280xp: Reserve low IOVA range for Iris
>       arm64: dts: qcom: sm8350: Reserve low IOVA range for Iris
>       arm64: dts: qcom: sm8550: Reserve low IOVA range for Iris
>       arm64: dts: qcom: sm8650: Reserve low IOVA range for Iris
>       arm64: dts: qcom: sm8750: Reserve low IOVA range for Iris
>       arm64: dts: qcom: agatti: Reserve low IOVA range for Venus
>       arm64: dts: qcom: kodiak: Reserve low IOVA range for Venus
>       arm64: dts: qcom: msm8916: Reserve low IOVA range for Venus
>       arm64: dts: qcom: msm8996: Reserve low IOVA range for Venus
>       arm64: dts: qcom: msm8998: Reserve low IOVA range for Venus
>       arm64: dts: qcom: sc7180: Reserve low IOVA range for Venus
>       arm64: dts: qcom: sdm630: Reserve low IOVA range for Venus
>       arm64: dts: qcom: sdm845: Reserve low IOVA range for Venus
>       arm64: dts: qcom: sm6115: Reserve low IOVA range for Venus
>       arm64: dts: qcom: sm8250: Reserve low IOVA range for Venus
>       arm64: dts: qcom: talos: Reserve low IOVA range for Venus
> 

-- 
With best wishes
Dmitry