From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E1F3023C8DE for ; Fri, 7 Feb 2025 16:33:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738946007; cv=none; b=DzPq8bES6WvovLuqDVXfslmKlpCgkPf2I6FpQ1FJtXvosVnVc9PXPZfI08yA5W3l1peMD32jsLmIkeyDv0MNKapUNipliJYdN/lDa2PEN9vh60KqYrtdCG8UhQzcs04nH3LyiVWE/FkdhHRMKnsxGZ34iI6xpzdm8rOzZ2KpP3A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1738946007; c=relaxed/simple; bh=N2uS9yWPLD4E6ZHEuCHhrIKMkX02v4Rz8ruwE/3Kq40=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rCH39pXt1e1Fnm4Fahrt+LeCdC3T+2qcBJfjgPuWeW8Puo/WPIZOFkl98tEJ1pftRyajekQh0IjwOaqCJF0xaizlHaDi8PY8CjrJzJaz2K7MYwpIl7gB44M28FmYH45Dpno7v49X5ELQ3zOHhZ2JbsLG3etWljalmid7uVCtq2A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=qs3BCIO9; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="qs3BCIO9" Received: from pendragon.ideasonboard.com (81-175-209-231.bb.dnainternet.fi [81.175.209.231]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 436442BA; Fri, 7 Feb 2025 17:32:09 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1738945929; bh=N2uS9yWPLD4E6ZHEuCHhrIKMkX02v4Rz8ruwE/3Kq40=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=qs3BCIO9noT5nVvOJY1+N8hSoVlybPDgYi+8fhLhLTLdudUtUI9LGIaNlkX0IfTGI nQE9OAUWaj2ccAfl6PV6vBnjK4pqeYLt4XtjtVj0uTEkrGbhFaCxKP1hNNWUF9mKAM RnQKXWodw5LuGpOKWkH3ffHekxGcesVWrYcf58bQ= Date: Fri, 7 Feb 2025 18:33:17 +0200 From: Laurent Pinchart To: Sean Anderson Cc: Tomi Valkeinen , "open list:DRM DRIVERS FOR XILINX" , Maarten Lankhorst , David Airlie , Simona Vetter , Michal Simek , Maxime Ripard , open list , Thomas Zimmermann , Bart Van Assche , Dan Carpenter , "moderated list:ARM/ZYNQ ARCHITECTURE" Subject: Re: [PATCH v2 1/2] drm: zynqmp_dp: Fix a deadlock in zynqmp_dp_ignore_hpd_set() Message-ID: <20250207163317.GA5869@pendragon.ideasonboard.com> References: <20250207162528.1651426-1-sean.anderson@linux.dev> <20250207162528.1651426-2-sean.anderson@linux.dev> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250207162528.1651426-2-sean.anderson@linux.dev> Hi Sean, Bart, Thank you for the patch. On Fri, Feb 07, 2025 at 11:25:27AM -0500, Sean Anderson wrote: > 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 Reviewed-by: Laurent Pinchart > --- > > (no changes since v1) > > 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; > } > -- Regards, Laurent Pinchart