Re: [PATCH] arm64: dts: qcom: agatti: Make the ADSP remote heap no-map

[Christopher Obbard]

On Thu, 01 Oct 2026 11:52:47 +0300, Benjamin Kelenyi <benjamin@xxxxxxxx> wrote:
> The ADSP remote heap is declared as a reusable CMA pool. The ADSP has no
> IOMMU, so fastrpc hands the whole region to the DSP with
> qcom_scm_assign_mem() when it probes, while CMA keeps lending the pool's
> pages to movable allocations. Once memory runs low the kernel touches a
> page the DSP now owns, and the board resets without an oops.
> 
> On an Arduino UNO Q (QRB2210, 4 GB), writing and reading back 3.5 GB
> through the page cache resets the board within seconds. With fastrpc
> blacklisted, or with the heap declared no-map, the same test passes
> repeatedly.
> 
> [...]

Reviewed-by: Christopher Obbard <chris.obbard@xxxxxxxxxxxxxxxx>

-- 
Christopher Obbard