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From: David Carlier <devnexen@gmail.com>
To: Tejun Heo <tj@kernel.org>, David Vernet <dvernet@meta.com>
Cc: linux-kernel@vger.kernel.org, David Carlier <devnexen@gmail.com>
Subject: [PATCH] tools/sched_ext: scx_nest: zero-initialize stats counter array
Date: Wed, 11 Feb 2026 21:52:13 +0000	[thread overview]
Message-ID: <20260211215213.917724-1-devnexen@gmail.com> (raw)

The local cnts array in read_stats() is not initialized before being
accumulated into per-CPU stats, which may lead to reading garbage
values. Zero it out with memset alongside the existing stats array
initialization.

Signed-off-by: David Carlier <devnexen@gmail.com>
---
 tools/sched_ext/scx_flatcg.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/sched_ext/scx_flatcg.c b/tools/sched_ext/scx_flatcg.c
index cd85eb401179..bea76d060201 100644
--- a/tools/sched_ext/scx_flatcg.c
+++ b/tools/sched_ext/scx_flatcg.c
@@ -106,6 +106,7 @@ static void fcg_read_stats(struct scx_flatcg *skel, __u64 *stats)
 	__u32 idx;
 
 	memset(stats, 0, sizeof(stats[0]) * FCG_NR_STATS);
+	memset(cnts, 0, sizeof(cnts));
 
 	for (idx = 0; idx < FCG_NR_STATS; idx++) {
 		int ret, cpu;
-- 
2.51.0


             reply	other threads:[~2026-02-11 21:52 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-11 21:52 David Carlier [this message]
2026-02-12 17:29 ` [PATCH] tools/sched_ext: scx_nest: zero-initialize stats counter array Tejun Heo

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