Commit 6ec4836f authored by Liang He's avatar Liang He Committed by Michael Ellerman
Browse files

powerpc/pseries: Add missing of_node_put()s in hotplug-cpu.c 



In pseries_cpuhp_cache_use_count() and pseries_cpuhp_detach_nodes(),
we need carefully hold the reference returned by
of_find_next_cache_node() and use it to call of_node_put() to keep
refcount balance.

Signed-off-by: default avatarLiang He <windhl@126.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220621111701.4082889-1-windhl@126.com
parent d208d8c2

arch/powerpc/platforms/pseries/hotplug-cpu.c

+11 −4
Original line number Diff line number Diff line
@@ -619,17 +619,21 @@ static ssize_t dlpar_cpu_add(u32 drc_index) 
static unsigned int pseries_cpuhp_cache_use_count(const struct device_node *cachedn)

{

	unsigned int use_count = 0;

	struct device_node *dn;

	struct device_node *dn, *tn;



	WARN_ON(!of_node_is_type(cachedn, "cache"));



	for_each_of_cpu_node(dn) {

		if (of_find_next_cache_node(dn) == cachedn)

		tn = of_find_next_cache_node(dn);

		of_node_put(tn);

		if (tn == cachedn)

			use_count++;

	}



	for_each_node_by_type(dn, "cache") {

		if (of_find_next_cache_node(dn) == cachedn)

		tn = of_find_next_cache_node(dn);

		of_node_put(tn);

		if (tn == cachedn)

			use_count++;

	}
@@ -649,10 +653,13 @@ static int pseries_cpuhp_detach_nodes(struct device_node *cpudn) 


	dn = cpudn;

	while ((dn = of_find_next_cache_node(dn))) {

		if (pseries_cpuhp_cache_use_count(dn) > 1)

		if (pseries_cpuhp_cache_use_count(dn) > 1) {

			of_node_put(dn);

			break;

		}



		ret = of_changeset_detach_node(&cs, dn);

		of_node_put(dn);

		if (ret)

			goto out;

	}