[PATCH v1 3/4] arm64: dts: qcom: sm8250: Make the ADSP remote heap no-map

[Jianping Li]

The ADSP remote heap is declared as a reusable CMA pool. FastRPC
assigns the entire region to the DSP during probe without allocating
the pages from CMA. This allows movable HLOS allocations to use pages
within the region after HLOS access permissions have been revoked,
potentially causing synchronous external aborts.

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: 531ce288b6dd4 ("arm64: dts: qcom: sm8250: Add memory-region for audio PD")
Link: https://lore.kernel.org/all/20260619-sm8250-audio-v1-1-8a76e033e209@xxxxxxxxxxxxxxxx/
Signed-off-by: Jianping Li <jianping.li@xxxxxxxxxxxxxxxx>
---
 arch/arm64/boot/dts/qcom/sm8250.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/sm8250.dtsi b/arch/arm64/boot/dts/qcom/sm8250.dtsi
index f975c2183269..f415da478c99 100644
--- a/arch/arm64/boot/dts/qcom/sm8250.dtsi
+++ b/arch/arm64/boot/dts/qcom/sm8250.dtsi
@@ -867,7 +867,7 @@ cdsp_secure_heap: memory@8bf00000 {
 		adsp_rpc_remote_heap_mem: adsp-rpc-remote-heap {
 			compatible = "shared-dma-pool";
 			alloc-ranges = <0x0 0x80000000 0x0 0x80000000>;
-			reusable;
+			no-map;
 			alignment = <0x0 0x400000>;
 			size = <0x0 0x800000>;
 		};
-- 
2.43.0