From nobody Fri Sep 20 20:28:00 2024 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 5A3C2C77B72 for ; Mon, 17 Apr 2023 08:17:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230401AbjDQIRy (ORCPT ); Mon, 17 Apr 2023 04:17:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229741AbjDQIRu (ORCPT ); Mon, 17 Apr 2023 04:17:50 -0400 Received: from mailgw01.mediatek.com (unknown [60.244.123.138]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B0EB026B2; Mon, 17 Apr 2023 01:17:48 -0700 (PDT) X-UUID: 537a69fedcf811eda9a90f0bb45854f4-20230417 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Message-ID:Date:Subject:CC:To:From; bh=vtIb9tYbe6yjfReUyHamMXfyrKWMabuVK2QPQKV6Ies=; b=a9ZtKBFJTlDSMSeg+qF7t/jFa3YKH9vDkYaWS5e6uDR3UKzuMCKqt7lDOcGNpCUWcZJhuLzD6jifn1uoNHGKOuVa3yADsHLgDYuTDRR88gX+KZdhXuJHhI1aS3EZPbEWEDRMRuh0kAdk1egxVnz5syxJcKwuEkobkH27k+fzCbs=; X-CID-P-RULE: Release_Ham X-CID-O-INFO: VERSION:1.1.22,REQID:34a49bda-3911-4913-8900-ccc034b47e1b,IP:0,U RL:0,TC:0,Content:0,EDM:0,RT:0,SF:95,FILE:0,BULK:0,RULE:Release_Ham,ACTION :release,TS:95 X-CID-INFO: VERSION:1.1.22,REQID:34a49bda-3911-4913-8900-ccc034b47e1b,IP:0,URL :0,TC:0,Content:0,EDM:0,RT:0,SF:95,FILE:0,BULK:0,RULE:Spam_GS981B3D,ACTION :quarantine,TS:95 X-CID-META: VersionHash:120426c,CLOUDID:dc294e84-cd9c-45f5-8134-710979e3df0e,B ulkID:230417161743L1ENFHNP,BulkQuantity:0,Recheck:0,SF:38|29|28|17|19|48,T C:nil,Content:0,EDM:-3,IP:nil,URL:0,File:nil,Bulk:nil,QS:nil,BEC:nil,COL:0 ,OSI:0,OSA:0,AV:0 X-CID-BVR: 0,NGT X-CID-BAS: 0,NGT,0,_ X-UUID: 537a69fedcf811eda9a90f0bb45854f4-20230417 Received: from mtkmbs10n1.mediatek.inc [(172.21.101.34)] by mailgw01.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 1581083758; Mon, 17 Apr 2023 16:17:42 +0800 Received: from mtkmbs13n2.mediatek.inc (172.21.101.108) by mtkmbs10n2.mediatek.inc (172.21.101.183) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.25; Mon, 17 Apr 2023 16:17:41 +0800 Received: from mhfsdcap04.gcn.mediatek.inc (10.17.3.154) by mtkmbs13n2.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.2.1118.25 via Frontend Transport; Mon, 17 Apr 2023 16:17:41 +0800 From: Yunfei Dong To: Hans Verkuil , Mauro Carvalho Chehab CC: Pina Chen , Yunfei Dong , , , , Subject: [PATCH] media: v4l2-mem2mem: add lock to protect parameter num_rdy Date: Mon, 17 Apr 2023 16:17:40 +0800 Message-ID: <20230417081740.26075-1-yunfei.dong@mediatek.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Getting below error when using KCSAN to check the driver. Adding lock to protect parameter num_rdy when getting the value with function: v4l2_m2m_num_src_bufs_ready/v4l2_m2m_num_dst_bufs_ready. kworker/u16:3: [name:report&]BUG: KCSAN: data-race in v4l2_m2m_buf_queue kworker/u16:3: [name:report&] kworker/u16:3: [name:report&]read-write to 0xffffff8105f35b94 of 1 bytes by= task 20865 on cpu 7: kworker/u16:3:=C2=A0 v4l2_m2m_buf_queue+0xd8/0x10c Signed-off-by: Pina Chen Signed-off-by: Yunfei Dong --- include/media/v4l2-mem2mem.h | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) diff --git a/include/media/v4l2-mem2mem.h b/include/media/v4l2-mem2mem.h index bb9de6a899e0..d6c8eb2b5201 100644 --- a/include/media/v4l2-mem2mem.h +++ b/include/media/v4l2-mem2mem.h @@ -593,7 +593,14 @@ void v4l2_m2m_buf_queue(struct v4l2_m2m_ctx *m2m_ctx, static inline unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx) { - return m2m_ctx->out_q_ctx.num_rdy; + unsigned int num_buf_rdy; + unsigned long flags; + + spin_lock_irqsave(&m2m_ctx->out_q_ctx.rdy_spinlock, flags); + num_buf_rdy =3D m2m_ctx->out_q_ctx.num_rdy; + spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock, flags); + + return num_buf_rdy; } =20 /** @@ -605,7 +612,14 @@ unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m= 2m_ctx *m2m_ctx) static inline unsigned int v4l2_m2m_num_dst_bufs_ready(struct v4l2_m2m_ctx *m2m_ctx) { - return m2m_ctx->cap_q_ctx.num_rdy; + unsigned int num_buf_rdy; + unsigned long flags; + + spin_lock_irqsave(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags); + num_buf_rdy =3D m2m_ctx->cap_q_ctx.num_rdy; + spin_unlock_irqrestore(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags); + + return num_buf_rdy; } =20 /** --=20 2.18.0