From 6ec4836fa15a0ff02e3a382ad6b1920c728a8c95 Mon Sep 17 00:00:00 2001 From: Liang He Date: Tue, 21 Jun 2022 19:17:01 +0800 Subject: [PATCH] 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: Liang He Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220621111701.4082889-1-windhl@126.com --- arch/powerpc/platforms/pseries/hotplug-cpu.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c index 0f8cd8b..e0a7ac5 100644 --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c @@ -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; } -- 2.7.4