On 12/14/22 01:17, Krzysztof Kozlowski wrote:
On 13/12/2022 15:07, Sibi Sankar wrote:
The memory region allocated using dma_alloc_attr with no kernel mapping
attribute set would still be a part of the linear kernel map. Any access
to this region by the application processor after assigning it to the
remote Q6 will result in a XPU violation. Fix this by replacing the
dynamically allocated memory region with a no-map carveout and unmap the
modem metadata memory region before passing control to the remote Q6.
Reported-by: Amit Pundir <amit.pundir@xxxxxxxxxx>
Fixes: 6c5a9dc2481b ("remoteproc: qcom: Make secure world call for mem ownership switch")
Signed-off-by: Sibi Sankar <quic_sibis@xxxxxxxxxxx>
---
Thank you for your patch. There is something to discuss/improve.
return ret < 0 ? ret : 0;
@@ -1882,6 +1899,26 @@ static int q6v5_alloc_memory_region(struct q6v5 *qproc)
qproc->mpss_phys = qproc->mpss_reloc = r.start;
qproc->mpss_size = resource_size(&r);
+ if (!child) {
+ node = of_parse_phandle(qproc->dev->of_node, "memory-region", 2);
+ } else {
+ child = of_get_child_by_name(qproc->dev->of_node, "metadata");
Bindings do not allow to have child "metadata", do they?
memory-region property was used to specify mba/mpss region in a phandle
array only from SC7180 SoC. All the older dtbs in the wild/upstream
still had sub-nodes to achieve the same. Patch 3 allows for a sub-set
of the SoCs (MSM8996/MSM8998/SDM845) to use metadata as a sub-node so
as to not break bindings when newer kernel uses a older dtb.
- Sibi
+ node = of_parse_phandle(child, "memory-region", 0);
+ of_node_put(child);
+ }
+
+ if (!node)
+ return 0;
+
+ ret = of_address_to_resource(node, 0, &r);
+ of_node_put(node);
+ if (ret) {
+ dev_err(qproc->dev, "unable to resolve metadata region\n");
+ return ret;
+ }
+
+ qproc->mdata_phys = r.start;
+
return 0;
}
Best regards,
Krzysztof
