From patchwork Thu Feb 6 19:41:18 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Anderson X-Patchwork-Id: 13963654 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 03251C02199 for ; Thu, 6 Feb 2025 19:42:17 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 85B1810E92E; Thu, 6 Feb 2025 19:42:16 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=linux.dev header.i=@linux.dev header.b="GHa1uwp2"; dkim-atps=neutral Received: from out-174.mta0.migadu.com (out-174.mta0.migadu.com [91.218.175.174]) by gabe.freedesktop.org (Postfix) with ESMTPS id 88DB410E92E for ; Thu, 6 Feb 2025 19:42:15 +0000 (UTC) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1738870928; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nZK/bu+U+BunpfC6VHKB5s7S43oPvXJGJkXPxJV9DLc=; b=GHa1uwp2L4ZpkRxR8aMWI3YDryRt/1t3jE/emX03upQMoAirq6MpvaHREEZiCsqLbA+B67 x2k7uL+sLJD5CjAFi6jUGHbvz1bRPpxXy8e1lY/u8aOcpNr+xdRd152UPv1O0NoHVx5fx0 kcePpf8A6GFUM+jpQrAa7pHiKpqa63k= From: Sean Anderson To: Laurent Pinchart , Tomi Valkeinen , dri-devel@lists.freedesktop.org (open list:DRM DRIVERS FOR XILINX) Cc: Thomas Zimmermann , linux-arm-kernel@lists.infradead.org (moderated list:ARM/ZYNQ ARCHITECTURE), linux-kernel@vger.kernel.org (open list), David Airlie , Dan Carpenter , Michal Simek , Maxime Ripard , Simona Vetter , Maarten Lankhorst , Bart Van Assche , Sean Anderson Subject: [PATCH 1/2] drm: zynqmp_dp: Fix a deadlock in zynqmp_dp_ignore_hpd_set() Date: Thu, 6 Feb 2025 14:41:18 -0500 Message-Id: <20250206194117.1496245-2-sean.anderson@linux.dev> In-Reply-To: <20250206194117.1496245-1-sean.anderson@linux.dev> References: <20250206194117.1496245-1-sean.anderson@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" From: Bart Van Assche Instead of attempting the same mutex twice, lock and unlock it. This bug has been detected by the Clang thread-safety analyzer. Cc: Sean Anderson Cc: Tomi Valkeinen Fixes: 28edaacb821c ("drm: zynqmp_dp: Add debugfs interface for compliance testing") Signed-off-by: Bart Van Assche Reviewed-by: Sean Anderson Signed-off-by: Sean Anderson --- drivers/gpu/drm/xlnx/zynqmp_dp.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c index 979f6d3239ba..189a08cdc73c 100644 --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c @@ -2295,7 +2295,7 @@ static int zynqmp_dp_ignore_hpd_set(void *data, u64 val) mutex_lock(&dp->lock); dp->ignore_hpd = val; - mutex_lock(&dp->lock); + mutex_unlock(&dp->lock); return 0; }