[tip: sched/core] cpuacct: Convert BUG_ON() to WARN_ON_ONCE()

[tip-bot2 for Andrey Ryabinin]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     c7ccbf4b6174e32c130892570db06d0f496cfef0
Gitweb:        https://git.kernel.org/tip/c7ccbf4b6174e32c130892570db06d0f496cfef0
Author:        Andrey Ryabinin <arbn@xxxxxxxxxxxxxxx>
AuthorDate:    Mon, 15 Nov 2021 19:46:05 +03:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Tue, 23 Nov 2021 09:55:22 +01:00

cpuacct: Convert BUG_ON() to WARN_ON_ONCE()

Replace fatal BUG_ON() with more safe WARN_ON_ONCE() in cpuacct_cpuusage_read().

Signed-off-by: Andrey Ryabinin <arbn@xxxxxxxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Daniel Jordan <daniel.m.jordan@xxxxxxxxxx>
Acked-by: Tejun Heo <tj@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20211115164607.23784-2-arbn@xxxxxxxxxxxxxxx
---
 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 893eece..f347cf9 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
 	/*