From mboxrd@z Thu Jan 1 00:00:00 1970 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 5DA3AC001B0 for ; Mon, 24 Jul 2023 01:52:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232615AbjGXBv7 (ORCPT ); Sun, 23 Jul 2023 21:51:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232600AbjGXBvq (ORCPT ); Sun, 23 Jul 2023 21:51:46 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F5507EE2; Sun, 23 Jul 2023 18:42:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C83E360FB4; Mon, 24 Jul 2023 01:35:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4378FC433C9; Mon, 24 Jul 2023 01:35:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690162557; bh=ve8GlTcDx3xxhHd+mTKMYwS4ODpTdL2prrI9QupPcAY=; h=From:To:Cc:Subject:Date:From; b=PKJu2ZaQk6qIv7uP5/ds8QgTcGHiGuheln3oxDsz+U+xXtf0CtpJT/h9qV1G5lvPK jZZcmKroBGe+weU2RqfBa6OtkI5teEqYSt+mu5ERaR3sakpL/UwdnNg+fyyEPk12WC W9YiP13FGEOr8DacoKFVuJ3p65V7ZuvAAwPLeHNM28jfZNdgkIIAJdEgX8Bo82BTPd 6g2Shw8boqzQbv4cMduCFhkSLGuL2nZSKlfurmoe5kDmJT+Whm980w7vxY6WmGQlNT 8Q4iGYBd15woC0tEqvwftB/RnPEncVv8/siZ/QFTtS/g9M3uJNfEWLaDLnsB4qubE4 tkWVVwJaZywiw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Yunfei Dong , Pina Chen , Hans Verkuil , Sasha Levin , matthias.bgg@gmail.com, linux-media@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org Subject: [PATCH AUTOSEL 4.14 1/9] media: v4l2-mem2mem: add lock to protect parameter num_rdy Date: Sun, 23 Jul 2023 21:35:43 -0400 Message-Id: <20230724013554.2334965-1-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 4.14.320 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Yunfei Dong [ Upstream commit 56b5c3e67b0f9af3f45cf393be048ee8d8a92694 ] 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:  v4l2_m2m_buf_queue+0xd8/0x10c Signed-off-by: Pina Chen Signed-off-by: Yunfei Dong Signed-off-by: Hans Verkuil Signed-off-by: Sasha Levin --- 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 e157d5c9b224e..239bcc4b7e95a 100644 --- a/include/media/v4l2-mem2mem.h +++ b/include/media/v4l2-mem2mem.h @@ -392,7 +392,14 @@ 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 = m2m_ctx->out_q_ctx.num_rdy; + spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock, flags); + + return num_buf_rdy; } /** @@ -404,7 +411,14 @@ unsigned int v4l2_m2m_num_src_bufs_ready(struct v4l2_m2m_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 = m2m_ctx->cap_q_ctx.num_rdy; + spin_unlock_irqrestore(&m2m_ctx->cap_q_ctx.rdy_spinlock, flags); + + return num_buf_rdy; } /** -- 2.39.2