[PATCH 20/23] memory: tegra30-emc: fix interconnect registration race

Johan Hovold
2023-02-01T10:16:49Z

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: d5ef16ba5fbe ("memory: tegra20: Support interconnect framework")
Cc: stable@vger.kernel.org # 5.11
Cc: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
---
drivers/memory/tegra/tegra30-emc.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/memory/tegra/tegra30-emc.c b/drivers/memory/tegra/tegra30-emc.c
index 77706e9bc543..c91e9b7e2e01 100644
--- a/drivers/memory/tegra/tegra30-emc.c
+++ b/drivers/memory/tegra/tegra30-emc.c
@@ -1533,15 +1533,13 @@ 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";
@@ -1562,12 +1560,14 @@ 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