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

Johan Hovold posted 23 patches 2 years, 7 months ago
There is a newer version of this series
[PATCH 08/23] interconnect: qcom: rpm: fix registration race
Posted by Johan Hovold 2 years, 7 months ago
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(-)

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;
 }
-- 
2.39.1
Re: [PATCH 08/23] interconnect: qcom: rpm: fix registration race
Posted by Jun Nie 2 years, 7 months ago
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>
Re: [PATCH 08/23] interconnect: qcom: rpm: fix registration race
Posted by Konrad Dybcio 2 years, 7 months ago

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;
>  }