perf: Fix the nr_addr_filters fix

[ Upstream commit 388a1fb7da6aaa1970c7e2a7d7fcd983a87a8484 ]

Thomas reported that commit 652ffc2104ec ("perf/core: Fix narrow
startup race when creating the perf nr_addr_filters sysfs file") made
the entire attribute group vanish, instead of only the nr_addr_filters
attribute.

Additionally a stray return.

Insufficient coffee was involved with both writing and merging the
patch.

Fixes: 652ffc2104ec ("perf/core: Fix narrow startup race when creating the perf nr_addr_filters sysfs file")
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Link: https://lkml.kernel.org/r/20231122100756.GP8262@noisy.programming.kicks-ass.net
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f22c540..fe543e7 100644 (file)
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -11422,12 +11422,10 @@ static umode_t pmu_dev_is_visible(struct kobject *kobj, struct attribute *a, int
        struct device *dev = kobj_to_dev(kobj);
        struct pmu *pmu = dev_get_drvdata(dev);
 
-       if (!pmu->nr_addr_filters)
+       if (n == 2 && !pmu->nr_addr_filters)
                return 0;
 
        return a->mode;
-
-       return 0;
 }
 
 static struct attribute_group pmu_dev_attr_group = {