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

From: Bryan O'Donoghue

Date: Fri Aug 07 2026 - 04:52:33 EST


On 07/08/2026 09:24, 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.
LGTM

For the series.

Reviewed-by: Bryan O'Donoghue <bod@xxxxxxxxxx>

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bod