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 95AD4C4332F for ; Wed, 9 Nov 2022 14:24:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231434AbiKIOYE (ORCPT ); Wed, 9 Nov 2022 09:24:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58320 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231512AbiKIOXp (ORCPT ); Wed, 9 Nov 2022 09:23:45 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C171B27B0F for ; Wed, 9 Nov 2022 06:21:44 -0800 (PST) Received: from pendragon.ideasonboard.com (117.145-247-81.adsl-dyn.isp.belgacom.be [81.247.145.117]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 9FDB5896; Wed, 9 Nov 2022 15:21:42 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1668003702; bh=kP5lC0vCldZuVd7ukcL4OuhKGJfq527jSr9BMS6LjxQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YS+x2KWmsZNgtsyH6EfEhLBfJKSAlbi5DgNlGN7Y0g+/b8Luh/UiLTUtTDMqwI/Ia 1oCpbIqcqljqF9SpzFS8G5Uq5HQHqxN/o+6V5IpcqlJFHRTb5lAjS78bZiKqzj1Me0 ymo2e5OxlO3nJ0Ju3J7VpIyZqfeOUp0VzGkjBAdM= Date: Wed, 9 Nov 2022 16:21:23 +0200 From: Laurent Pinchart To: Nathan Chancellor Cc: Hyun Kwon , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, Nick Desaulniers , Tom Rix , Kees Cook , Sami Tolvanen , llvm@lists.linux.dev, linux-kernel@vger.kernel.org, patches@lists.linux.dev, Nathan Huckleberry , Dan Carpenter Subject: Re: [PATCH v2] drm: xlnx: Fix return type of zynqmp_dp_bridge_mode_valid Message-ID: References: <20221109001424.1422495-1-nathan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20221109001424.1422495-1-nathan@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Nathan, Thank you for the patch. On Tue, Nov 08, 2022 at 05:14:25PM -0700, Nathan Chancellor wrote: > From: Nathan Huckleberry > > The mode_valid field in drm_bridge_helper_funcs is expected to be of > type > enum drm_mode_status (* mode_valid) (struct drm_bridge *bridge, > struct drm_display_mode *mode); > > The mismatched return type breaks forward edge kCFI since the underlying > function definition does not match the function hook definition. A new > warning in clang will catch this at compile time: > > drivers/gpu/drm/xlnx/zynqmp_dp.c:1573:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_bridge *, const struct drm_display_info *, const struct drm_display_mode *)' with an expression of type 'int (struct drm_bridge *, const struct drm_display_info *, const struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict] > .mode_valid = zynqmp_dp_bridge_mode_valid, > ^~~~~~~~~~~~~~~~~~~~~~~~~~~ > 1 error generated. > > The return type of zynqmp_dp_bridge_mode_valid should be changed from > int to enum drm_mode_status. > > Reported-by: Dan Carpenter > Link: https://github.com/ClangBuiltLinux/linux/issues/1703 > Link: https://github.com/ClangBuiltLinux/linux/issues/1750 > Signed-off-by: Nathan Huckleberry > Reviewed-by: Laurent Pinchart > [nathan: Rebase on drm-misc-next and fix conflicts > Add note about new clang warning] > Signed-off-by: Nathan Chancellor > --- > > Please consider picking this up so that it makes 6.2. I'll send a pull request shortly. > v2: > - Take over for Nathan, as he is busy with other matters. > - Rebase on drm-misc-next and resolve conflicts. > - Add a note about new clang warning that will catch this issue at > compile time. > > v1: https://lore.kernel.org/20220913205600.155172-1-nhuck@google.com/ > > drivers/gpu/drm/xlnx/zynqmp_dp.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c > index 7c9ae167eac7..0a7b466446fb 100644 > --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c > +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c > @@ -1362,9 +1362,10 @@ static void zynqmp_dp_bridge_detach(struct drm_bridge *bridge) > zynqmp_dp_aux_cleanup(dp); > } > > -static int zynqmp_dp_bridge_mode_valid(struct drm_bridge *bridge, > - const struct drm_display_info *info, > - const struct drm_display_mode *mode) > +static enum drm_mode_status > +zynqmp_dp_bridge_mode_valid(struct drm_bridge *bridge, > + const struct drm_display_info *info, > + const struct drm_display_mode *mode) > { > struct zynqmp_dp *dp = bridge_to_dp(bridge); > int rate; > > base-commit: 1a0257c352638916fdaffaac2ddedb8e049312f3 -- Regards, Laurent Pinchart