diff mbox series

[08/23] interconnect: qcom: rpm: fix registration race

Message ID 20230201101559.15529-9-johan+linaro@kernel.org (mailing list archive)
State New
Headers show
Series interconnect: fix racy provider registration | expand

Commit Message

Johan Hovold Feb. 1, 2023, 10:15 a.m. UTC
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.

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

Fixes: 62feb14ee8a3 ("interconnect: qcom: Consolidate interconnect RPM support")
Fixes: 30c8fa3ec61a ("interconnect: qcom: Add MSM8916 interconnect provider driver")
Cc: stable@vger.kernel.org	# 5.7
Cc: Jun Nie <jun.nie@linaro.org>
Cc: Georgi Djakov <georgi.djakov@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/interconnect/qcom/icc-rpm.c | 23 ++++++++++++-----------
 1 file changed, 12 insertions(+), 11 deletions(-)

Comments

Konrad Dybcio Feb. 3, 2023, 2:53 a.m. UTC | #1
On 1.02.2023 11:15, Johan Hovold wrote:
> 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.
> 
> Switch to using the new API where the provider is not registered until
> after it has been fully initialised.
> 
> Fixes: 62feb14ee8a3 ("interconnect: qcom: Consolidate interconnect RPM support")
> Fixes: 30c8fa3ec61a ("interconnect: qcom: Add MSM8916 interconnect provider driver")
> Cc: stable@vger.kernel.org	# 5.7
> Cc: Jun Nie <jun.nie@linaro.org>
> Cc: Georgi Djakov <georgi.djakov@linaro.org>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>

Konrad
>  drivers/interconnect/qcom/icc-rpm.c | 23 ++++++++++++-----------
>  1 file changed, 12 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c
> index da595059cafd..4d0997b210f7 100644
> --- a/drivers/interconnect/qcom/icc-rpm.c
> +++ b/drivers/interconnect/qcom/icc-rpm.c
> @@ -502,7 +502,6 @@ int qnoc_probe(struct platform_device *pdev)
>  	}
>  
>  	provider = &qp->provider;
> -	INIT_LIST_HEAD(&provider->nodes);
>  	provider->dev = dev;
>  	provider->set = qcom_icc_set;
>  	provider->pre_aggregate = qcom_icc_pre_bw_aggregate;
> @@ -510,11 +509,7 @@ int qnoc_probe(struct platform_device *pdev)
>  	provider->xlate_extended = qcom_icc_xlate_extended;
>  	provider->data = data;
>  
> -	ret = icc_provider_add(provider);
> -	if (ret) {
> -		dev_err(dev, "error adding interconnect provider: %d\n", ret);
> -		goto err_disable_clks;
> -	}
> +	icc_provider_init(provider);
>  
>  	for (i = 0; i < num_nodes; i++) {
>  		size_t j;
> @@ -522,7 +517,7 @@ int qnoc_probe(struct platform_device *pdev)
>  		node = icc_node_create(qnodes[i]->id);
>  		if (IS_ERR(node)) {
>  			ret = PTR_ERR(node);
> -			goto err;
> +			goto err_remove_nodes;
>  		}
>  
>  		node->name = qnodes[i]->name;
> @@ -536,19 +531,25 @@ int qnoc_probe(struct platform_device *pdev)
>  	}
>  	data->num_nodes = num_nodes;
>  
> +	ret = icc_provider_register(provider);
> +	if (ret)
> +		goto err_remove_nodes;
> +
>  	platform_set_drvdata(pdev, qp);
>  
>  	/* Populate child NoC devices if any */
>  	if (of_get_child_count(dev->of_node) > 0) {
>  		ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
>  		if (ret)
> -			goto err;
> +			goto err_deregister_provider;
>  	}
>  
>  	return 0;
> -err:
> +
> +err_deregister_provider:
> +	icc_provider_deregister(provider);
> +err_remove_nodes:
>  	icc_nodes_remove(provider);
> -	icc_provider_del(provider);
>  err_disable_clks:
>  	clk_bulk_disable_unprepare(qp->num_clks, qp->bus_clks);
>  
> @@ -560,9 +561,9 @@ int qnoc_remove(struct platform_device *pdev)
>  {
>  	struct qcom_icc_provider *qp = platform_get_drvdata(pdev);
>  
> +	icc_provider_deregister(&qp->provider);
>  	icc_nodes_remove(&qp->provider);
>  	clk_bulk_disable_unprepare(qp->num_clks, qp->bus_clks);
> -	icc_provider_del(&qp->provider);
>  
>  	return 0;
>  }
Jun Nie Feb. 3, 2023, 4:06 a.m. UTC | #2
Johan Hovold <johan+linaro@kernel.org> 于2023年2月1日周三 18:16写道:
>
> 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.
>
> Switch to using the new API where the provider is not registered until
> after it has been fully initialised.
>
> Fixes: 62feb14ee8a3 ("interconnect: qcom: Consolidate interconnect RPM support")
> Fixes: 30c8fa3ec61a ("interconnect: qcom: Add MSM8916 interconnect provider driver")
> Cc: stable@vger.kernel.org      # 5.7
> Cc: Jun Nie <jun.nie@linaro.org>
> Cc: Georgi Djakov <georgi.djakov@linaro.org>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---
>  drivers/interconnect/qcom/icc-rpm.c | 23 ++++++++++++-----------
>  1 file changed, 12 insertions(+), 11 deletions(-)
>
Reviewed-by: Jun Nie <jun.nie@linaro.org>
diff mbox series

Patch

diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c
index da595059cafd..4d0997b210f7 100644
--- a/drivers/interconnect/qcom/icc-rpm.c
+++ b/drivers/interconnect/qcom/icc-rpm.c
@@ -502,7 +502,6 @@  int qnoc_probe(struct platform_device *pdev)
 	}
 
 	provider = &qp->provider;
-	INIT_LIST_HEAD(&provider->nodes);
 	provider->dev = dev;
 	provider->set = qcom_icc_set;
 	provider->pre_aggregate = qcom_icc_pre_bw_aggregate;
@@ -510,11 +509,7 @@  int qnoc_probe(struct platform_device *pdev)
 	provider->xlate_extended = qcom_icc_xlate_extended;
 	provider->data = data;
 
-	ret = icc_provider_add(provider);
-	if (ret) {
-		dev_err(dev, "error adding interconnect provider: %d\n", ret);
-		goto err_disable_clks;
-	}
+	icc_provider_init(provider);
 
 	for (i = 0; i < num_nodes; i++) {
 		size_t j;
@@ -522,7 +517,7 @@  int qnoc_probe(struct platform_device *pdev)
 		node = icc_node_create(qnodes[i]->id);
 		if (IS_ERR(node)) {
 			ret = PTR_ERR(node);
-			goto err;
+			goto err_remove_nodes;
 		}
 
 		node->name = qnodes[i]->name;
@@ -536,19 +531,25 @@  int qnoc_probe(struct platform_device *pdev)
 	}
 	data->num_nodes = num_nodes;
 
+	ret = icc_provider_register(provider);
+	if (ret)
+		goto err_remove_nodes;
+
 	platform_set_drvdata(pdev, qp);
 
 	/* Populate child NoC devices if any */
 	if (of_get_child_count(dev->of_node) > 0) {
 		ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
 		if (ret)
-			goto err;
+			goto err_deregister_provider;
 	}
 
 	return 0;
-err:
+
+err_deregister_provider:
+	icc_provider_deregister(provider);
+err_remove_nodes:
 	icc_nodes_remove(provider);
-	icc_provider_del(provider);
 err_disable_clks:
 	clk_bulk_disable_unprepare(qp->num_clks, qp->bus_clks);
 
@@ -560,9 +561,9 @@  int qnoc_remove(struct platform_device *pdev)
 {
 	struct qcom_icc_provider *qp = platform_get_drvdata(pdev);
 
+	icc_provider_deregister(&qp->provider);
 	icc_nodes_remove(&qp->provider);
 	clk_bulk_disable_unprepare(qp->num_clks, qp->bus_clks);
-	icc_provider_del(&qp->provider);
 
 	return 0;
 }