Re: [PATCH v1] arm64: dts: qcom: talos: Make the ADSP remote heap no-map

[Val Packett <val@packett.cool>]

On 10/14/26 5:38 AM, Jianping Li wrote:

> The ADSP remote heap is declared as a reusable CMA pool. FastRPC
> assigns the entire region to the DSP through qcom_scm_assign_mem()
> during probe without allocating the pages from CMA. Consequently,
> the pages remain available for movable HLOS allocations even after
> HLOS access to the region has been revoked.
>
> On Talos, GPU stress testing triggers a synchronous external abort
> when zram accesses pages within the ADSP remote heap.
>
> Replace reusable with no-map to prevent the region from being reused
> for normal kernel allocations and exclude it from the kernel's
> standard memory mapping.
>
> Fixes: b0b51a5f1911f ("arm64: dts: qcom: talos: Add memory-region for audio PD")
> Link: https://lore.kernel.org/all/20260424-talosaudio-v3-1-9e2ad5d78a2e@oss.qualcomm.com/
> Signed-off-by: Jianping Li <jianping.li@oss.qualcomm.com>
> ---
>   arch/arm64/boot/dts/qcom/talos.dtsi | 2 +-

This also applies to: glymur, agatti, sm8250, kodiak, sm8750.. (at least 
those I've found by grepping for the adsp_rpc_remote_heap_mem label)

I've been hitting the SEA on a kodiak phone (sm7325-motorola-dubai) 
constantly with just light everyday usage:

Internal error: synchronous external abort: 0000000096000010 [#1]  SMP
CPU: 7 UID: 10000 PID: 26485 Comm: pool-24 Tainted: G   M    W         
7.3.0-rc6-next-20261009-uwu+ #167 PREEMPT(full)
Tainted: [M]=MACHINE_CHECK, [W]=WARN
Hardware name: motorola Motorola Edge 30 (Tianma)/Motorola Edge 30 
(Tianma), BIOS 2026.07-gca7686425f32-dirty 07/01/2026
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : clear_page+0x30/0x70
lr : prep_new_page+0x94/0x178 ...
Call trace:
  clear_page+0x30/0x70 (P)
  get_page_from_freelist+0x1bd8/0x1c00
  __alloc_frozen_pages_noprof+0x1cc/0x3f8
  alloc_pages_mpol+0x124/0x210
  vma_alloc_folio_noprof+0x124/0x200
  vma_alloc_zeroed_movable_folio+0x3c/0x50
  do_pte_missing+0x9e0/0xf80
  ...


This no-map does seem to fix it.


Thanks,
~val