From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 3516D443D for ; Mon, 31 Oct 2022 22:24:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1E666C433D7; Mon, 31 Oct 2022 22:24:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1667255072; bh=c430a9vtJ9VLpdvhysJooW/JnUHf5Y1ouH47JEN2P14=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=WTWhq78uRNLiqVdI4TGtO46oG1p4v/zCTpBX8wI2zjC/49Ea74Bx/W3KE9TmaCzdF hxwiG13aeaNMJGIRuNr92vPbxk2TxonFCbZ1ucQ4wk+pL2aFBFyOWDzuUSV7nL3Laf 6SE3mn0W61+oV9Uf3RpX26XUKDYq/sLpULaZOHlyffJZ6BvYyJHbNSxOLMTagKFUUN xlNnIDnqGganQImu8fzJCmlVWV/U0rB3e4qfbWnRjhV4VL6J+4gqlqdxRwOGP4lDHl F39PT3miQm9J2K8S4mc0WnZHEAtfLoORFJ3cTkRpf2FsrrK6XKSPlV+PCrCaq8vk9g sHy3KIFTr/27w== Date: Mon, 31 Oct 2022 15:24:30 -0700 From: Nathan Chancellor To: Nathan Huckleberry Cc: Dan Carpenter , llvm@lists.linux.dev, Hyun Kwon , Laurent Pinchart , David Airlie , Daniel Vetter , Michal Simek , Nick Desaulniers , Tom Rix , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] drm: xlnx: Fix return type of zynqmp_dp_connector_mode_valid Message-ID: References: <20220913205600.155172-1-nhuck@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220913205600.155172-1-nhuck@google.com> Hi all, On Tue, Sep 13, 2022 at 01:56:00PM -0700, Nathan Huckleberry wrote: > The mode_valid field in drm_connector_helper_funcs is expected to be of > type > enum drm_mode_status (* mode_valid) (struct drm_connector *connector, > 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. > > The return type of zynqmp_dp_connector_mode_valid should be changed from > int to enum drm_mode_status. > > Reported-by: Dan Carpenter > Link: https://github.com/ClangBuiltLinux/linux/issues/1703 > Cc: llvm@lists.linux.dev > Signed-off-by: Nathan Huckleberry > --- > drivers/gpu/drm/xlnx/zynqmp_dp.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/xlnx/zynqmp_dp.c b/drivers/gpu/drm/xlnx/zynqmp_dp.c > index d14612b34796..f571b08d23d3 100644 > --- a/drivers/gpu/drm/xlnx/zynqmp_dp.c > +++ b/drivers/gpu/drm/xlnx/zynqmp_dp.c > @@ -1352,8 +1352,9 @@ zynqmp_dp_connector_best_encoder(struct drm_connector *connector) > return &dp->encoder; > } > > -static int zynqmp_dp_connector_mode_valid(struct drm_connector *connector, > - struct drm_display_mode *mode) > +static enum drm_mode_status > +zynqmp_dp_connector_mode_valid(struct drm_connector *connector, > + struct drm_display_mode *mode) > { > struct zynqmp_dp *dp = connector_to_dp(connector); > u8 max_lanes = dp->link_config.max_lanes; > -- > 2.37.2.789.g6183377224-goog > > Did this patch get lost somewhere? I do not see it picked up. It is needed to avoid a new WIP warning from clang for catching these CFI failures: drivers/gpu/drm/xlnx/zynqmp_dp.c:1396:16: error: incompatible function pointer types initializing 'enum drm_mode_status (*)(struct drm_connector *, struct drm_display_mode *)' with an expression of type 'int (struct drm_connector *, struct drm_display_mode *)' [-Werror,-Wincompatible-function-pointer-types-strict] .mode_valid = zynqmp_dp_connector_mode_valid, ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1 error generated. Cheers, Nathan