[PATCH 18/23] memory: tegra124-emc: fix interconnect registration race

Johan Hovold posted 23 patches 2 years, 7 months ago
There is a newer version of this series
[PATCH 18/23] memory: tegra124-emc: fix interconnect 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: 380def2d4cf2 ("memory: tegra124: Support interconnect framework")
Cc: stable@vger.kernel.org      # 5.12
Cc: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
 drivers/memory/tegra/tegra124-emc.c | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/memory/tegra/tegra124-emc.c b/drivers/memory/tegra/tegra124-emc.c
index 85bc936c02f9..00ed2b6a0d1b 100644
--- a/drivers/memory/tegra/tegra124-emc.c
+++ b/drivers/memory/tegra/tegra124-emc.c
@@ -1351,15 +1351,13 @@ static int tegra_emc_interconnect_init(struct tegra_emc *emc)
 	emc->provider.aggregate = soc->icc_ops->aggregate;
 	emc->provider.xlate_extended = emc_of_icc_xlate_extended;
 
-	err = icc_provider_add(&emc->provider);
-	if (err)
-		goto err_msg;
+	icc_provider_init(&emc->provider);
 
 	/* create External Memory Controller node */
 	node = icc_node_create(TEGRA_ICC_EMC);
 	if (IS_ERR(node)) {
 		err = PTR_ERR(node);
-		goto del_provider;
+		goto err_msg;
 	}
 
 	node->name = "External Memory Controller";
@@ -1380,12 +1378,14 @@ static int tegra_emc_interconnect_init(struct tegra_emc *emc)
 	node->name = "External Memory (DRAM)";
 	icc_node_add(node, &emc->provider);
 
+	err = icc_provider_register(&emc->provider);
+	if (err)
+		goto remove_nodes;
+
 	return 0;
 
 remove_nodes:
 	icc_nodes_remove(&emc->provider);
-del_provider:
-	icc_provider_del(&emc->provider);
 err_msg:
 	dev_err(emc->dev, "failed to initialize ICC: %d\n", err);
 
-- 
2.39.1
Re: [PATCH 18/23] memory: tegra124-emc: fix interconnect registration race
Posted by Krzysztof Kozlowski 2 years, 7 months ago
On 01/02/2023 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: 380def2d4cf2 ("memory: tegra124: Support interconnect framework")
> Cc: stable@vger.kernel.org      # 5.12
> Cc: Dmitry Osipenko <digetx@gmail.com>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---


Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof