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 632F0C00528 for ; Mon, 24 Jul 2023 01:49:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232620AbjGXBt2 (ORCPT ); Sun, 23 Jul 2023 21:49:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231159AbjGXBrc (ORCPT ); Sun, 23 Jul 2023 21:47:32 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A5DD5199D; Sun, 23 Jul 2023 18:39:58 -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 A852C61047; Mon, 24 Jul 2023 01:34:48 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1DD3FC433C8; Mon, 24 Jul 2023 01:34:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690162488; bh=vSBc29n/0V7Gek75PwWlCSvfClOhA/69+Dc3CrxfUTU=; h=From:To:Cc:Subject:Date:From; b=Ac6wylaPc6rZYS56Bp9lv/AHtx2Jdn+anAuWEiEWrAS8PUPv/ySFzyGx5s9zg6bRI Out09OtfYU0eO+eb3SugTA4u6rVox8EnLhjyK5UY1IDXTk7vG5r4TnvfWoPgSGczGp LPnWeJZdmAy/F/tByXUYCjoo4tE6Z6u+Zi1BW7InYqZDwU8jeyLDN1UVjx5UWlOTGy +DCVHUiW3eixbJo3VDpUK+vS4Au2V7yW8xfxwPtFUeXBDEEHTjt+bUUARR28TQ34Ik ymDLN0XJxKOQzibY62TKGdeJQg/jpZFoZwI0yxok6LjEp64/p+PLOWvmS/gRlxPQfl hVpEXcOl78jBw== 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 4.19 1/9] media: v4l2-mem2mem: add lock to protect parameter num_rdy Date: Sun, 23 Jul 2023 21:34:37 -0400 Message-Id: <20230724013445.2334326-1-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 4.19.288 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 d655720e16a15..62c67e9e190c0 100644 --- a/include/media/v4l2-mem2mem.h +++ b/include/media/v4l2-mem2mem.h @@ -405,7 +405,14 @@ 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; } /** @@ -417,7 +424,14 @@ 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