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 32987C04E69 for ; Mon, 24 Jul 2023 01:44:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232398AbjGXBog (ORCPT ); Sun, 23 Jul 2023 21:44:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46710 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232331AbjGXBmz (ORCPT ); Sun, 23 Jul 2023 21:42:55 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8859A1BE4; Sun, 23 Jul 2023 18:37:33 -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 F16CE60F66; Mon, 24 Jul 2023 01:33:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67A8CC433C7; Mon, 24 Jul 2023 01:33:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690162408; bh=HBPxB4RSNktNe65BuqWS+L5dNFVXfE7ZABDYXvs5vsc=; h=From:To:Cc:Subject:Date:From; b=G0HO7mSzs/MsPLmcuwZw/bTJKEMBOkvpGKx01tPeq2NN8skcgKQiEEVCvB30w+Ci9 E6OE83Jejzt6rTzsJUR+K0D4XuB4lNCvhQWvBLkJ9dC2gvI8n2TI+6FnNir0SlpbgE yFhSUXklDDoJ+uM6ZEk7U3LxmSuWbH6XfxKj2f0DXERhUQS+Fo/+CkcPtV39sDid+C kLr7Tesd42ZG4V2GeP60ZdznQAnkgGNvRN3fqVEnMUg6WFYQaNeIrgwQESYfhPUZyr CK6sAFvbdITpapu5cPv1RvgZbY+G25F4CraVv+Q5601HhtKDZZKUv/+e1JcKLGBU0p GUnRA65nx/MrQ== 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 5.15 01/24] media: v4l2-mem2mem: add lock to protect parameter num_rdy Date: Sun, 23 Jul 2023 21:33:02 -0400 Message-Id: <20230724013325.2332084-1-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 5.15.121 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 5a91b548ecc0c..8d52c4506762d 100644 --- a/include/media/v4l2-mem2mem.h +++ b/include/media/v4l2-mem2mem.h @@ -588,7 +588,14 @@ 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; } /** @@ -600,7 +607,14 @@ 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