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 499BA377ECC; Mon, 30 Mar 2026 16:43:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774889011; cv=none; b=OajMLmwAg1pvhGGSNj+EIEHULKFgyl5hKKSvN4E+TPOo8HhkGOQu5jaYT7M4o5oCuGpIdF5J1qzSgWpVpfS38maHL1KS7nCSr7+Vv5dpjprnjYs2AVpHg5WbVEU51Ij8F8ibCVjoOHOfwKOoshEtL6ELaV/enpYfq82Xpq3Qcg4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774889011; c=relaxed/simple; bh=p1jo0copgAEo8xrTWfLXOYQHLuRM6ONtDy8aiRv2lQ8=; h=Date:From:To:Cc:Subject:Message-ID:MIME-Version:Content-Type: Content-Disposition:In-Reply-To; b=PeAtg851Mu99KqVGsRjtrH7DQ4hDkq/9Evp/r9s6VUs4T8LgAt2OVYb5ywF6M6wmhXP4qKtNS+7rXiY6Os0KxgpXCdKXVUomHkh6taFWikw2FRvrSpDv073YxQixCw7iqTkapVv1KzncwC3hvDtOX+nrmwTODzCY1m8etjLBSqg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=f2IVOxLR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="f2IVOxLR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7D836C4CEF7; Mon, 30 Mar 2026 16:43:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774889010; bh=p1jo0copgAEo8xrTWfLXOYQHLuRM6ONtDy8aiRv2lQ8=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=f2IVOxLR6fhfrRkVXW7aZqz9z0nY+Tu32lPSojGKbpcR/PKUXKv1Uh4IvfneuqA3V 33e8otrxJFUKEt+YcyI1rEQz/k0l/bga4kWvFB1gQ/PZEpJo9781A5bA+zCaXho0Lb XGzljxjoeFrDZe6GgsnmznfrLGA2GF72TsqmlJuWM4EOLliSCUCtVBlJ328eT19huU PtxPKhddWi43eKbqNS8HEuR9ZKNZZaEtl0p5vxoWvR06HgPN+TRLkFAXAbd6KpGpl5 DSgi2zdC/c2uEmuFUrf1aOfI8Ubgu84xoNR/CmzpuevVuUY86ATQADKxwu7tim1enx JO+VlMbO3dVTQ== Date: Mon, 30 Mar 2026 11:43:27 -0500 From: Bjorn Helgaas To: kernel test robot Cc: Simon Richter , llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev, linux-pci@vger.kernel.org Subject: Re: [pci:vga 3/5] drivers/gpu/drm/i915/display/intel_vga.c:68:2: error: ignoring return value of function declared with 'warn_unused_result' attribute Message-ID: <20260330164327.GA81786@bhelgaas> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <202603300336.G53JumVL-lkp@intel.com> On Mon, Mar 30, 2026 at 04:02:59AM +0800, kernel test robot wrote: > Hi Simon, > > First bad commit (maybe != root cause): > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git vga > head: 21b082bd2a45704a6f7e69c190c8287a3d011ea9 > commit: dc582b5ed4b749335b947258d4874df628726632 [3/5] PCI/VGA: Mark vga_get() and wrappers as __must_check > config: x86_64-randconfig-011-20260329 (https://download.01.org/0day-ci/archive/20260330/202603300336.G53JumVL-lkp@intel.com/config) > compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261) > reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260330/202603300336.G53JumVL-lkp@intel.com/reproduce) > > If you fix the issue in a separate patch/commit (i.e. not just a new version of > the same patch/commit), kindly add following tags > | Reported-by: kernel test robot > | Closes: https://lore.kernel.org/oe-kbuild-all/202603300336.G53JumVL-lkp@intel.com/ > > All errors (new ones prefixed by >>): > > >> drivers/gpu/drm/i915/display/intel_vga.c:68:2: error: ignoring return value of function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result] > 68 | vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); > | ^~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~ > drivers/gpu/drm/i915/display/intel_vga.c:93:2: error: ignoring return value of function declared with 'warn_unused_result' attribute [-Werror,-Wunused-result] > 93 | vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); > | ^~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~ > 2 errors generated. Dropped the commits related to this, see https://lore.kernel.org/all/20260330161802.GA79047@bhelgaas > vim +/warn_unused_result +68 drivers/gpu/drm/i915/display/intel_vga.c > > 0c80d60ae63461 Ville Syrjälä 2025-04-17 43 > 4fb8783165b7c6 Jani Nikula 2019-10-01 44 /* Disable the VGA plane that we never use */ > 4b6e05c43b7542 Ville Syrjälä 2024-09-06 45 void intel_vga_disable(struct intel_display *display) > 4fb8783165b7c6 Jani Nikula 2019-10-01 46 { > 4b6e05c43b7542 Ville Syrjälä 2024-09-06 47 struct pci_dev *pdev = to_pci_dev(display->drm->dev); > 4b6e05c43b7542 Ville Syrjälä 2024-09-06 48 i915_reg_t vga_reg = intel_vga_cntrl_reg(display); > 0c80d60ae63461 Ville Syrjälä 2025-04-17 49 enum pipe pipe; > 0c80d60ae63461 Ville Syrjälä 2025-04-17 50 u32 tmp; > 4fb8783165b7c6 Jani Nikula 2019-10-01 51 u8 sr1; > 4fb8783165b7c6 Jani Nikula 2019-10-01 52 > 0c80d60ae63461 Ville Syrjälä 2025-04-17 53 tmp = intel_de_read(display, vga_reg); > 0c80d60ae63461 Ville Syrjälä 2025-04-17 54 if (tmp & VGA_DISP_DISABLE) > a3af0140663dc3 Emil Velikov 2021-06-04 55 return; > a3af0140663dc3 Emil Velikov 2021-06-04 56 > 0c80d60ae63461 Ville Syrjälä 2025-04-17 57 if (display->platform.cherryview) > 0c80d60ae63461 Ville Syrjälä 2025-04-17 58 pipe = REG_FIELD_GET(VGA_PIPE_SEL_MASK_CHV, tmp); > 0c80d60ae63461 Ville Syrjälä 2025-04-17 59 else if (has_vga_pipe_sel(display)) > 0c80d60ae63461 Ville Syrjälä 2025-04-17 60 pipe = REG_FIELD_GET(VGA_PIPE_SEL_MASK, tmp); > 0c80d60ae63461 Ville Syrjälä 2025-04-17 61 else > 0c80d60ae63461 Ville Syrjälä 2025-04-17 62 pipe = PIPE_A; > 0c80d60ae63461 Ville Syrjälä 2025-04-17 63 > 0c80d60ae63461 Ville Syrjälä 2025-04-17 64 drm_dbg_kms(display->drm, "Disabling VGA plane on pipe %c\n", > 0c80d60ae63461 Ville Syrjälä 2025-04-17 65 pipe_name(pipe)); > 0c80d60ae63461 Ville Syrjälä 2025-04-17 66 > 4fb8783165b7c6 Jani Nikula 2019-10-01 67 /* WaEnableVGAAccessThroughIOPort:ctg,elk,ilk,snb,ivb,vlv,hsw */ > 4fb8783165b7c6 Jani Nikula 2019-10-01 @68 vga_get_uninterruptible(pdev, VGA_RSRC_LEGACY_IO); > f0bb41fad02e03 Jani Nikula 2022-02-02 69 outb(0x01, VGA_SEQ_I); > f0bb41fad02e03 Jani Nikula 2022-02-02 70 sr1 = inb(VGA_SEQ_D); > f0bb41fad02e03 Jani Nikula 2022-02-02 71 outb(sr1 | VGA_SR01_SCREEN_OFF, VGA_SEQ_D); > 4fb8783165b7c6 Jani Nikula 2019-10-01 72 vga_put(pdev, VGA_RSRC_LEGACY_IO); > 4fb8783165b7c6 Jani Nikula 2019-10-01 73 udelay(300); > 4fb8783165b7c6 Jani Nikula 2019-10-01 74 > 4b6e05c43b7542 Ville Syrjälä 2024-09-06 75 intel_de_write(display, vga_reg, VGA_DISP_DISABLE); > 4b6e05c43b7542 Ville Syrjälä 2024-09-06 76 intel_de_posting_read(display, vga_reg); > 4fb8783165b7c6 Jani Nikula 2019-10-01 77 } > 4fb8783165b7c6 Jani Nikula 2019-10-01 78 > > :::::: The code at line 68 was first introduced by commit > :::::: 4fb8783165b7c6fb4b52428dbb80da8554e5fd1e drm/i915/display: abstract all vgaarb access to intel_vga.[ch] > > :::::: TO: Jani Nikula > :::::: CC: Jani Nikula > > -- > 0-DAY CI Kernel Test Service > https://github.com/intel/lkp-tests/wiki