From:   Andrey Ryabinin <arbn@yandex-team.com>
To:     Ingo Molnar <mingo@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>
Cc:     Andrey Ryabinin <arbn@yandex-team.com>,
        Daniel Jordan <daniel.m.jordan@oracle.com>,
        Tejun Heo <tj@kernel.org>, Juri Lelli <juri.lelli@redhat.com>,
        Vincent Guittot <vincent.guittot@linaro.org>,
        Dietmar Eggemann <dietmar.eggemann@arm.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
        Daniel Bristot de Oliveira <bristot@redhat.com>,
        cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
        Dan Schatzberg <schatzberg.dan@gmail.com>
Subject: [PATCH v3 2/4] cpuacct: convert BUG_ON() to WARN_ON_ONCE()
Date:   Mon, 15 Nov 2021 19:46:05 +0300
Message-Id: <20211115164607.23784-2-arbn@yandex-team.com>
In-Reply-To: <20211115164607.23784-1-arbn@yandex-team.com>
References: <20211115164607.23784-1-arbn@yandex-team.com>
MIME-Version: 1.0
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Replace fatal BUG_ON() with more safe WARN_ON_ONCE() in cpuacct_cpuusage_read().

Signed-off-by: Andrey Ryabinin <arbn@yandex-team.com>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
---
 kernel/sched/cpuacct.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/kernel/sched/cpuacct.c b/kernel/sched/cpuacct.c
index 893eece65bfd..f347cf9e4634 100644
--- a/kernel/sched/cpuacct.c
+++ b/kernel/sched/cpuacct.c
@@ -106,7 +106,8 @@ static u64 cpuacct_cpuusage_read(struct cpuacct *ca, int cpu,
 	 * We allow index == CPUACCT_STAT_NSTATS here to read
 	 * the sum of usages.
 	 */
-	BUG_ON(index > CPUACCT_STAT_NSTATS);
+	if (WARN_ON_ONCE(index > CPUACCT_STAT_NSTATS))
+		return 0;
 
 #ifndef CONFIG_64BIT
 	/*
-- 
2.32.0