Re: [PATCH v5 3/3] arm64: dts: freescale: add DT overlay for MX95-15x15-FRDM RPMSG usage

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
- [Medium] dts: overlapping reserved-memory nodes due to mismatched node names
--

commit 9406ad5f04c442814590c1435b754dffaa93d0ea
Author: Laurentiu Mihalcea <laurentiu.mihalcea@nxp.com>

arm64: dts: freescale: add DT overlay for MX95-15x15-FRDM RPMSG usage

This commit adds an RPMSG device tree overlay for the MX95-15x15-FRDM
board to support remoteproc and audio over rpmsg-usecases alongside the
mx95evkrpmsg system manager configuration.

> diff --git a/arch/arm64/boot/dts/freescale/imx95-15x15-frdm-rpmsg.dtso b/arch/arm64/boot/dts/freescale/imx95-15x15-frdm-rpmsg.dtso
> new file mode 100644
> index 0000000000000..c3deb277edabf
> --- /dev/null
> +++ b/arch/arm64/boot/dts/freescale/imx95-15x15-frdm-rpmsg.dtso
> @@ -0,0 +1,81 @@
[ ... ]
> +	reserved-memory {
> +		#address-cells = <2>;
> +		#size-cells = <2>;
> +
> +		vdev0vring0: memory@88000000 {
> +			reg = <0 0x88000000 0 0x8000>;
> +			no-map;
> +		};

[Severity: Medium]
Does this node name conflict with the base device tree?

The base device tree imx95-15x15-frdm.dts defines this region using a
different name:

vdev0vring0: vdev0vring0@88000000 {
        reg = <0 0x88000000 0 0x8000>;
        no-map;
};

Because device tree overlays merge by exact node name and unit-address,
using a generic name like memory@88000000 here will prevent the overlay
from overriding or merging with the existing node. Instead, it will create
duplicate sibling nodes under /reserved-memory with identical physical
addresses.

Could this duplication cause the kernel's early memory reservation code
(__rmem_check_for_overlap) to detect overlaps and trigger 'OF: reserved mem:
OVERLAP detected!' errors during boot, or potentially duplicate DMA pools for
the same memory?

Would it be safer to reuse the exact base node names in the overlay, or omit
the reserved-memory block entirely if the base tree already provides the
necessary nodes?

[ ... ]

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261015-memory-region-name-v5-0-abc358b39a96@nxp.com?part=3