From: Bjorn Andersson <bjorn.andersson@linaro.org>
Date: Fri, 25 Jun 2021 23:49:03 +0000 (-0700)
Subject: interconnect: Sanity check that node isn't already on list
X-Git-Tag: howlett/maple/20220722_2~2448^2~7^2~5
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=9cc969675dea496b6689f576ddd4d8fd172705c5;p=users%2Fjedix%2Flinux-maple.git

interconnect: Sanity check that node isn't already on list

Broken interconnect providers might add the same node multiple times or
in multiple providers, which causes strange errors as the provider's
node list is later traversed.

Detect that a node already has an associated provider, complain and
reject the addition of the node, to aid the developer.

Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20210625234903.1324755-1-bjorn.andersson@linaro.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
---

diff --git a/drivers/interconnect/core.c b/drivers/interconnect/core.c
index 8a1e70e008764..fcb5d8eefb515 100644
--- a/drivers/interconnect/core.c
+++ b/drivers/interconnect/core.c
@@ -959,6 +959,9 @@ EXPORT_SYMBOL_GPL(icc_link_destroy);
  */
 void icc_node_add(struct icc_node *node, struct icc_provider *provider)
 {
+	if (WARN_ON(node->provider))
+		return;
+
 	mutex_lock(&icc_lock);
 
 	node->provider = provider;