From nobody Thu Dec 18 12:32:37 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00E2CC4332F for ; Mon, 11 Dec 2023 19:27:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344459AbjLKT13 (ORCPT ); Mon, 11 Dec 2023 14:27:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52882 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229661AbjLKT12 (ORCPT ); Mon, 11 Dec 2023 14:27:28 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id A46199F for ; Mon, 11 Dec 2023 11:27:34 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0B82F1007; Mon, 11 Dec 2023 11:28:21 -0800 (PST) Received: from e121345-lin.cambridge.arm.com (e121345-lin.cambridge.arm.com [10.1.196.40]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 5D7A53F762; Mon, 11 Dec 2023 11:27:33 -0800 (PST) From: Robin Murphy To: will@kernel.org Cc: mark.rutland@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, jeremy.linton@arm.com, ilkka@os.amperecomputing.com, renyu.zj@linux.alibaba.com Subject: [PATCH] perf/arm-cmn: Fail DTC counter allocation correctly Date: Mon, 11 Dec 2023 19:27:28 +0000 Message-Id: X-Mailer: git-send-email 2.39.2.101.g768bb238c484.dirty MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Calling arm_cmn_event_clear() before all DTC indices are allocated is wrong, and can lead to arm_cmn_event_add() erroneously clearing live counters from full DTCs where allocation fails. Since the DTC counters are only updated by arm_cmn_init_counter() after all DTC and DTM allocations succeed, nothing actually needs cleaning up in this case anyway, and it should just return directly as it did before. Fixes: 7633ec2c262f ("perf/arm-cmn: Rework DTC counters (again)") Signed-off-by: Robin Murphy Acked-by: Will Deacon --- drivers/perf/arm-cmn.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c index 86d970e74129..c584165b13ba 100644 --- a/drivers/perf/arm-cmn.c +++ b/drivers/perf/arm-cmn.c @@ -1816,7 +1816,7 @@ static int arm_cmn_event_add(struct perf_event *event= , int flags) idx =3D 0; while (cmn->dtc[j].counters[idx]) if (++idx =3D=3D CMN_DT_NUM_COUNTERS) - goto free_dtms; + return -ENOSPC; } hw->dtc_idx[j] =3D idx; } --=20 2.39.2.101.g768bb238c484.dirty