Re: [PATCH 00/22] media: iris: Restrict lower IOVA range for Venus and Iris VPUs
From: Dmitry Baryshkov
Date: Fri Aug 07 2026 - 06:09:41 EST
On Fri, Aug 07, 2026 at 02:35:29PM +0530, Vikash Garodia wrote:
>
> On 8/7/2026 2:29 PM, Dmitry Baryshkov wrote:
> > 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?
>
> By some, i assume you are referring to the 2 patches from Daniel. Kept it as
> part of this series to maintain the continuity with patches across other
> socs, other option would be to bring them as dependency and drop them from
> here.
So, your series should have been v2 at least. V1 has already sailed.
--
With best wishes
Dmitry