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 86AF1C001E0 for ; Mon, 24 Jul 2023 01:37:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231873AbjGXBhG (ORCPT ); Sun, 23 Jul 2023 21:37:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231917AbjGXBgh (ORCPT ); Sun, 23 Jul 2023 21:36:37 -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 6137A59F2; Sun, 23 Jul 2023 18:33:00 -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 023F560F29; Mon, 24 Jul 2023 01:31:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6E549C433CC; Mon, 24 Jul 2023 01:31:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690162306; bh=sPgqBc9MDblYXPHS71Myl2hrzTAGjCrucv1FSII+xSY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PtQYyWlGdOnS/jH+ZGCJWimp1grJZ870ZbuAmtEcoGrx0nrxAL7SvjUYHdKg6zQ/7 Np8RA9UxpR97BtTkCcF5YOMfrIXaN33he67Perlix7m6rFZNPM8XwHqQU34UF3OSMj LGXgMy8+6dbF3RO2KgZ3jnJZu8X3HSrN13mx5nTtOcq2gLF3scOxYyNpQpD7cIxwwW 0EExZx8tkUGTVe0DPgs7wwGgyabBw4X91xi/TvDIcSaRhKi3E5yoBCMYjuCrl4qCTl JxXS9ddCIk8/Q5VnFSYZWrvXvLt7m10uwjIPCMbfoLxXUP6kiwuUtPB6UPljOH26U2 1O8tG11yY7yHQ== 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 6.4 03/40] media: v4l2-mem2mem: add lock to protect parameter num_rdy Date: Sun, 23 Jul 2023 21:31:03 -0400 Message-Id: <20230724013140.2327815-3-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230724013140.2327815-1-sashal@kernel.org> References: <20230724013140.2327815-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.4.5 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 bb9de6a899e07..d6c8eb2b52019 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 = m2m_ctx->out_q_ctx.num_rdy; + spin_unlock_irqrestore(&m2m_ctx->out_q_ctx.rdy_spinlock, flags); + + return num_buf_rdy; } /** @@ -605,7 +612,14 @@ 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