Re: [PATCH v4 4/6] arm64: dts: imx8mm: imx8mp: Add CM DTOs for Data Modul i.MX8M Mini and Plus eDM SBC

[Marek Vasut <marex@nabladev.com>]

On 7/13/26 5:45 PM, Frank Li wrote:
> On Sun, Jul 05, 2026 at 08:24:38PM +0000, sashiko-bot@kernel.org wrote:
>> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
>> - [Medium] The virtio device buffer node is named `vdevbuffer` instead of `vdev0buffer`, bypassing the driver's carveout exclusion logic.
>> --
>>
>> commit b1e78cbda66a659316ae8170db75a75bd2d9d9d2
>> Author: Marek Vasut <marex@nabladev.com>
>>
>> arm64: dts: imx8mm: imx8mp: Add CM DTOs for Data Modul i.MX8M Mini and Plus eDM SBC
>>
>> This commit adds device tree overlays for the CM4/CM7 cores on the Data
>> Modul i.MX8M Mini and Plus eDM SBCs. The overlays allow CM4/CM7 firmware
>> to be used with remoteproc and rpmsg without imposing the overhead on
>> every user of the platform.
>>
>> [ ... ]
>>
>>> diff --git a/arch/arm64/boot/dts/freescale/imx8mm-data-modul-edm-sbc-overlay-cm4.dtso b/arch/arm64/boot/dts/freescale/imx8mm-data-modul-edm-sbc-overlay-cm4.dtso
>>> new file mode 100644
>>> index 0000000000000..8d681c0eff0d4
>>> --- /dev/null
>>> +++ b/arch/arm64/boot/dts/freescale/imx8mm-data-modul-edm-sbc-overlay-cm4.dtso
>>> @@ -0,0 +1,56 @@
>> [ ... ]
>>> +		rsc_table: rsc-table@b80ff000 {
>>> +			reg = <0 0xb80ff000 0 0x1000>;
>>> +			no-map;
>>> +		};
>>> +
>>> +		vdevbuffer: vdevbuffer@b8400000 {
>>> +			compatible = "shared-dma-pool";
>>> +			reg = <0 0xb8400000 0 0x100000>;
>>
>> [Severity: Medium]
>> Will this node name bypass the driver's carveout exclusion logic?
>>
>> Looking at imx_rproc_prepare(), it iterates over memory-regions and checks
>> specifically for the name "vdev0buffer" to skip processing the vdev buffer:
>>
>> 	if (!strcmp(it.node->name, "rsc-table") ||
>> 	    !strcmp(it.node->name, "vdev0vring0") ||
>> 	    !strcmp(it.node->name, "vdev0vring1") ||
>> 	    strstarts(res.name, "vdev0buffer"))
>> 		continue;
>>
>> Because this node is named "vdevbuffer" instead of "vdev0buffer", it appears
>> it will be mapped as a generic carveout via ioremap_wc() and unintentionally
>> included in the remoteproc coredump.
>>
>> Could this node be renamed to "vdev0buffer" to avoid wasting vmalloc space
>> and bloating the coredump?
> 
> Look like make sense, please check it.
> 
> It is not good to use node-name as ABI. Laurentiu is working on use
> memory-region-namses.
The memory regionss are referenced from imx8mm-cm4 { } node via the 
memory-region property:

memory-region = <&vdevbuffer>, <&vdev0vring0>, <&vdev0vring1>, <&rsc_table>;