From nobody Tue Feb 10 18:21:33 2026 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.5]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 8AE5518C004 for ; Wed, 25 Sep 2024 14:32:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.5 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727274772; cv=none; b=uT4nQY2+7C6iA49LO/e8/+pcsudzdY9rKFEM+DI6MDtrEXyHEylrAG6728LZfBhH+t9pZV7/deqHWZJ53m2Q49B/sZmD7s5nvFoYNVjlLclA2BCXV2n+yaD0NcrPVfArJgESuPl7TSuyBgLTdexyEgKFYlvBRIKRsYbeS+P25sY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727274772; c=relaxed/simple; bh=9hXniMzHG8iE92aMEhzcFR7plZHS0qL/TXHqDgDnhPk=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=GnVQpsUB+xXTIXHY9FGmrnyrb0p5mjjLuJARcRdkwMPui835xYGlLuhFPbC0nZXPjL9ePLi6osOVOgT5gVFRCRIdS1ZD47IOlGAsWWA1yhb6k7veyqdHX1YTDRZgIDBv2k0GSarLzvUIybPL+jbfcHa5JTY5eswxCR8vbmehlzM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=dfL9K7oa; arc=none smtp.client-ip=220.197.31.5 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="dfL9K7oa" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:Subject:Date:Message-Id:MIME-Version; bh=7/NB/ v2fjTsmnyeIo9rDAFMjTCqI92mCnWuv5aDhiWo=; b=dfL9K7oa1gJVJZ2PTUQ5e S9Ae1QsUA8CShbWVfOoA2vmfEkzF+wbGMDdGlNJhmpkM4xqrf1Mo6JzsDc8gCLys +tVC1kCtNqdJXYKO+Geb7Q825dXpBQxK3GuHDdnqycdIn9K2TD1TIR7IgGwU8vlp OFgVbNWGRjKUiiY8VLlnQM= Received: from localhost.localdomain (unknown [193.203.214.57]) by gzga-smtp-mta-g2-2 (Coremail) with SMTP id _____wDn9EXeHvRmGMqpJA--.33673S8; Wed, 25 Sep 2024 22:32:14 +0800 (CST) From: ran xiaokai To: elver@google.com, tglx@linutronix.de, dvyukov@google.com Cc: kasan-dev@googlegroups.com, linux-kernel@vger.kernel.org, Ran Xiaokai Subject: [PATCH 4/4] kcsan, debugfs: avoid updating white/blacklist with the same value Date: Wed, 25 Sep 2024 14:31:54 +0000 Message-Id: <20240925143154.2322926-5-ranxiaokai627@163.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20240925143154.2322926-1-ranxiaokai627@163.com> References: <20240925143154.2322926-1-ranxiaokai627@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: _____wDn9EXeHvRmGMqpJA--.33673S8 X-Coremail-Antispam: 1Uf129KBjvdXoWrZFW3Cry7CryxtF1xuw1UAwb_yoW3CwbEq3 ykXay8Kr45JFZxur1v93yrXrsYy345AF40va4fKa47J3Z8K3ZIkFZ3XrWqgrZ5uFWxGryr A3s8Krn8WryftjkaLaAFLSUrUUUUjb8apTn2vfkv8UJUUUU8Yxn0WfASr-VFAUDa7-sFnT 9fnUUvcSsGvfC2KfnxnUUI43ZEXa7IU05l1DUUUUU== X-CM-SenderInfo: xudq5x5drntxqwsxqiywtou0bp/xtbB0hhlTGb0HcIX-AAAsF Content-Type: text/plain; charset="utf-8" From: Ran Xiaokai When userspace passes a same white/blacklist value as it for now, the update is actually not necessary. Signed-off-by: Ran Xiaokai --- kernel/kcsan/debugfs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/kcsan/debugfs.c b/kernel/kcsan/debugfs.c index d5e624c37125..6b05115d5b73 100644 --- a/kernel/kcsan/debugfs.c +++ b/kernel/kcsan/debugfs.c @@ -142,6 +142,9 @@ static ssize_t set_report_filterlist_whitelist(bool whi= telist) old_list =3D rcu_dereference_protected(rp_flist, lockdep_is_held(&rp_flist_mutex)); =20 + if (old_list->whitelist =3D=3D whitelist) + goto out; + new_list =3D kzalloc(sizeof(*new_list), GFP_KERNEL); if (!new_list) { ret =3D -ENOMEM; --=20 2.15.2