[PATCH v1 1/4] arm64: dts: qcom: kodiak: 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 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HLOS access to the region has been revoked.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 Kodiak, a synchronous external abort was reported during storage
testing when the kernel accessed memory within the ADSP remote heap.
The faulting address was outside the HLOS stage-2 mapping.

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: 9d7d847ff1c50 ("arm64: dts: qcom: kodiak: avoid EFI overlap for ADSP remote heap")
Link: https://lore.kernel.org/all/20260423063502.484-1-jianping.li@xxxxxxxxxxxxxxxx/
Signed-off-by: Jianping Li <jianping.li@xxxxxxxxxxxxxxxx>
---
 arch/arm64/boot/dts/qcom/kodiak.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/boot/dts/qcom/kodiak.dtsi b/arch/arm64/boot/dts/qcom/kodiak.dtsi
index 8c7523602d27..057d7e62b2dd 100644
--- a/arch/arm64/boot/dts/qcom/kodiak.dtsi
+++ b/arch/arm64/boot/dts/qcom/kodiak.dtsi
@@ -194,7 +194,7 @@ rmtfs_mem: rmtfs@9c900000 {
 		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