[PATCH 6.1 133/198] interconnect: qcom: osm-l3: fix registration race

[Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>]

From: Johan Hovold <johan+linaro@xxxxxxxxxx>

commit 174941ed28a3573db075da46d95b4dcf9d4c49c2 upstream.

The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to fail:

	of_icc_xlate_onecell: invalid index 0
	cpu cpu0: error -EINVAL: error finding src node
	cpu cpu0: dev_pm_opp_of_find_icc_paths: Unable to get path0: -22
	qcom-cpufreq-hw: probe of 18591000.cpufreq failed with error -22

Switch to using the new API where the provider is not registered until
after it has been fully initialised.

Fixes: 5bc9900addaf ("interconnect: qcom: Add OSM L3 interconnect provider support")
Cc: stable@xxxxxxxxxxxxxxx      # 5.7
Reviewed-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
Signed-off-by: Johan Hovold <johan+linaro@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230306075651.2449-6-johan+linaro@xxxxxxxxxx
Signed-off-by: Georgi Djakov <djakov@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 drivers/interconnect/qcom/osm-l3.c |   14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

--- a/drivers/interconnect/qcom/osm-l3.c
+++ b/drivers/interconnect/qcom/osm-l3.c
@@ -216,8 +216,8 @@ static int qcom_osm_l3_remove(struct pla
 {
 	struct qcom_osm_l3_icc_provider *qp = platform_get_drvdata(pdev);
 
+	icc_provider_deregister(&qp->provider);
 	icc_nodes_remove(&qp->provider);
-	icc_provider_del(&qp->provider);
 
 	return 0;
 }
@@ -303,14 +303,9 @@ static int qcom_osm_l3_probe(struct plat
 	provider->set = qcom_osm_l3_set;
 	provider->aggregate = icc_std_aggregate;
 	provider->xlate = of_icc_xlate_onecell;
-	INIT_LIST_HEAD(&provider->nodes);
 	provider->data = data;
 
-	ret = icc_provider_add(provider);
-	if (ret) {
-		dev_err(&pdev->dev, "error adding interconnect provider\n");
-		return ret;
-	}
+	icc_provider_init(provider);
 
 	for (i = 0; i < num_nodes; i++) {
 		size_t j;
@@ -333,12 +328,15 @@ static int qcom_osm_l3_probe(struct plat
 	}
 	data->num_nodes = num_nodes;
 
+	ret = icc_provider_register(provider);
+	if (ret)
+		goto err;
+
 	platform_set_drvdata(pdev, qp);
 
 	return 0;
 err:
 	icc_nodes_remove(provider);
-	icc_provider_del(provider);
 
 	return ret;
 }