Commit 2012a9e2 authored by Xiaomeng Tong's avatar Xiaomeng Tong Committed by Will Deacon
Browse files

perf: qcom_l2_pmu: fix an incorrect NULL check on list iterator 



The bug is here:
	return cluster;

The list iterator value 'cluster' will *always* be set and non-NULL
by list_for_each_entry(), so it is incorrect to assume that the
iterator value will be NULL if the list is empty or no element
is found.

To fix the bug, return 'cluster' when found, otherwise return NULL.

Cc: stable@vger.kernel.org
Fixes: 21bdbb71 ("perf: add qcom l2 cache perf events driver")
Signed-off-by: default avatarXiaomeng Tong <xiam0nd.tong@gmail.com>
Link: https://lore.kernel.org/r/20220327055733.4070-1-xiam0nd.tong@gmail.com


Signed-off-by: default avatarWill Deacon <will@kernel.org>
parent 4dfa1f36

drivers/perf/qcom_l2_pmu.c

+3 −3
Original line number Diff line number Diff line
@@ -736,7 +736,7 @@ static struct cluster_pmu *l2_cache_associate_cpu_with_cluster( 
{

	u64 mpidr;

	int cpu_cluster_id;

	struct cluster_pmu *cluster = NULL;

	struct cluster_pmu *cluster;



	/*

	 * This assumes that the cluster_id is in MPIDR[aff1] for
@@ -758,10 +758,10 @@ static struct cluster_pmu *l2_cache_associate_cpu_with_cluster( 
			 cluster->cluster_id);

		cpumask_set_cpu(cpu, &cluster->cluster_cpus);

		*per_cpu_ptr(l2cache_pmu->pmu_cluster, cpu) = cluster;

		break;

		return cluster;

	}



	return cluster;

	return NULL;

}



static int l2cache_pmu_online_cpu(unsigned int cpu, struct hlist_node *node)