[PATCH 17/23] memory: tegra: fix interconnect registration race

Johan Hovold
2023-02-01T10:16:53Z

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: 06f079816d4c ("memory: tegra-mc: Add 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/mc.c | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/memory/tegra/mc.c b/drivers/memory/tegra/mc.c
index 592907546ee6..5cd28619ea9f 100644
--- a/drivers/memory/tegra/mc.c
+++ b/drivers/memory/tegra/mc.c
@@ -794,16 +794,12 @@ static int tegra_mc_interconnect_setup(struct tegra_mc *mc)
mc->provider.aggregate = mc->soc->icc_ops->aggregate;
mc->provider.xlate_extended = mc->soc->icc_ops->xlate_extended;

- err = icc_provider_add(&mc->provider);
- if (err)
- return err;
+ icc_provider_init(&mc->provider);

/* create Memory Controller node */
node = icc_node_create(TEGRA_ICC_MC);
- if (IS_ERR(node)) {
- err = PTR_ERR(node);
- goto del_provider;
- }
+ if (IS_ERR(node))
+ return PTR_ERR(node);

node->name = "Memory Controller";
icc_node_add(node, &mc->provider);
@@ -830,12 +826,14 @@ static int tegra_mc_interconnect_setup(struct tegra_mc *mc)
goto remove_nodes;
}

+ err = icc_provider_register(&mc->provider);
+ if (err)
+ goto remove_nodes;
+
return 0;

remove_nodes:
icc_nodes_remove(&mc->provider);
-del_provider:
- icc_provider_del(&mc->provider);

return err;
}
--
2.39.1