linux-kernel - [PATCH v2 1/5] lib/test_cpumask: drop cpu_possible

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Message-Id: <6dfd4d3a4d77f97f13ab3f22bc53c96c38ba908e.1661007339.git.sander@svanheule.net>
Date:   Sat, 20 Aug 2022 17:03:09 +0200
From:   Sander Vanheule <sander@...nheule.net>
To:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Brendan Higgins <brendan.higgins@...ux.dev>,
        David Gow <davidgow@...gle.com>,
        linux-kselftest@...r.kernel.org, kunit-dev@...glegroups.com
Cc:     Maíra Canal <mairacanal@...eup.net>,
        linux-kernel@...r.kernel.org,
        Sander Vanheule <sander@...nheule.net>
Subject: [PATCH v2 1/5] lib/test_cpumask: drop cpu_possible_mask full test

When the number of CPUs that can possibly be brought online is known at
boot time, e.g. when HOTPLUG is disabled, nr_cpu_ids may be smaller than
NR_CPUS. In that case, cpu_possible_mask would not be completely filled,
and cpumask_full(cpu_possible_mask) can return false for valid system
configurations.

Fixes: c41e8866c28c ("lib/test: introduce cpumask KUnit test suite")
Link: https://lore.kernel.org/lkml/346cb279-8e75-24b0-7d12-9803f2b41c73@riseup.net/
Reported-by: Maíra Canal <mairacanal@...eup.net>
Signed-off-by: Sander Vanheule <sander@...nheule.net>
Tested-by: Maíra Canal <mairacanal@...eup.net>
Reviewed-by: David Gow <davidgow@...gle.com>
---
Changes in v2:
Rewrite commit message to explain why this test is wrong

 lib/test_cpumask.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/lib/test_cpumask.c b/lib/test_cpumask.c
index a31a1622f1f6..4ebf9f5805f3 100644
--- a/lib/test_cpumask.c
+++ b/lib/test_cpumask.c
@@ -54,7 +54,6 @@ static cpumask_t mask_all;
 static void test_cpumask_weight(struct kunit *test)
 {
 	KUNIT_EXPECT_TRUE(test, cpumask_empty(&mask_empty));
-	KUNIT_EXPECT_TRUE(test, cpumask_full(cpu_possible_mask));
 	KUNIT_EXPECT_TRUE(test, cpumask_full(&mask_all));
 
 	KUNIT_EXPECT_EQ(test, 0, cpumask_weight(&mask_empty));
-- 
2.37.2