Commit 305f2547 authored by Macpaul Lin's avatar Macpaul Lin Committed by Ulf Hansson
Browse files

pmdomain: mtk-pm-domains: Fix spinlock recursion fix in probe 



Remove scpsys_get_legacy_regmap(), replacing its usage with
of_find_node_with_property(). Explicitly call of_node_get(np) before each
of_find_node_with_property() to maintain correct node reference counting.

The of_find_node_with_property() function "consumes" its input by calling
of_node_put() internally, whether or not it finds a match.  Currently,
dev->of_node (np) is passed multiple times in sequence without incrementing
its reference count, causing it to be decremented multiple times and
risking early memory release.

Adding of_node_get(np) before each call balances the reference count,
preventing premature node release.

Fixes: c1bac49f ("pmdomains: mtk-pm-domains: Fix spinlock recursion in probe")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarMacpaul Lin <macpaul.lin@mediatek.com>
Tested-by: default avatarLouis-Alexis Eyraud <louisalexis.eyraud@collabora.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
parent f8f9c1f4

drivers/pmdomain/mediatek/mtk-pm-domains.c

+6 −15
Original line number Diff line number Diff line
@@ -984,18 +984,6 @@ static void scpsys_domain_cleanup(struct scpsys *scpsys) 
	}

}



static struct device_node *scpsys_get_legacy_regmap(struct device_node *np, const char *pn)

{

	struct device_node *local_node;



	for_each_child_of_node(np, local_node) {

		if (of_property_present(local_node, pn))

			return local_node;

	}



	return NULL;

}



static int scpsys_get_bus_protection_legacy(struct device *dev, struct scpsys *scpsys)

{

	const u8 bp_blocks[3] = {
@@ -1017,7 +1005,8 @@ static int scpsys_get_bus_protection_legacy(struct device *dev, struct scpsys *s 
	 * this makes it then possible to allocate the array of bus_prot

	 * regmaps and convert all to the new style handling.

	 */

	node = scpsys_get_legacy_regmap(np, "mediatek,infracfg");

	of_node_get(np);

	node = of_find_node_with_property(np, "mediatek,infracfg");

	if (node) {

		regmap[0] = syscon_regmap_lookup_by_phandle(node, "mediatek,infracfg");

		of_node_put(node);
@@ -1030,7 +1019,8 @@ static int scpsys_get_bus_protection_legacy(struct device *dev, struct scpsys *s 
		regmap[0] = NULL;

	}



	node = scpsys_get_legacy_regmap(np, "mediatek,smi");

	of_node_get(np);

	node = of_find_node_with_property(np, "mediatek,smi");

	if (node) {

		smi_np = of_parse_phandle(node, "mediatek,smi", 0);

		of_node_put(node);
@@ -1048,7 +1038,8 @@ static int scpsys_get_bus_protection_legacy(struct device *dev, struct scpsys *s 
		regmap[1] = NULL;

	}



	node = scpsys_get_legacy_regmap(np, "mediatek,infracfg-nao");

	of_node_get(np);

	node = of_find_node_with_property(np, "mediatek,infracfg-nao");

	if (node) {

		regmap[2] = syscon_regmap_lookup_by_phandle(node, "mediatek,infracfg-nao");

		num_regmaps++;