Re: [PATCH] usb: gadget: uvc: add framebased stream support

From: kernel test robot <lkp@intel.com>
To: 3090101217@zju.edu.cn, laurent.pinchart@ideasonboard.com,
	balbi@kernel.org, gregkh@linuxfoundation.org, corbet@lwn.net,
	mchehab+huawei@kernel.org, rdunlap@infradead.org, bilbao@vt.edu,
	pawell@cadence.com
Cc: llvm@lists.linux.dev, kbuild-all@lists.01.org,
	linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org,
	Jing Leng <jleng@ambarella.com>
Subject: Re: [PATCH] usb: gadget: uvc: add framebased stream support
Date: Thu, 17 Feb 2022 02:22:45 +0800	[thread overview]
Message-ID: <202202170211.van9U4Ha-lkp@intel.com> (raw)
In-Reply-To: <20220216081651.9089-1-3090101217@zju.edu.cn>

Hi,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on usb/usb-testing]
[also build test WARNING on linus/master v5.17-rc4 next-20220216]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/3090101217-zju-edu-cn/usb-gadget-uvc-add-framebased-stream-support/20220216-162037
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
config: arm-randconfig-r023-20220216 (https://download.01.org/0day-ci/archive/20220217/202202170211.van9U4Ha-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0e628a783b935c70c80815db6c061ec84f884af5)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://github.com/0day-ci/linux/commit/475fba6b60329d9270b699550907a5e077cd84b6
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review 3090101217-zju-edu-cn/usb-gadget-uvc-add-framebased-stream-support/20220216-162037
        git checkout 475fba6b60329d9270b699550907a5e077cd84b6
        # save the config file to linux build tree
        mkdir build_dir
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash block// drivers/usb/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/usb/gadget/function/uvc_configfs.c:1091:3: warning: field  within 'struct uvcg_frame::(unnamed at drivers/usb/gadget/function/uvc_configfs.c:1068:2)' is less aligned than 'union uvcg_frame::(anonymous at drivers/usb/gadget/function/uvc_configfs.c:1091:3)' and is usually due to 'struct uvcg_frame::(unnamed at drivers/usb/gadget/function/uvc_configfs.c:1068:2)' being packed, which can lead to unaligned accesses [-Wunaligned-access]
                   union {
                   ^
   1 warning generated.

vim +1091 drivers/usb/gadget/function/uvc_configfs.c

  1060	
  1061	/* -----------------------------------------------------------------------------
  1062	 * streaming/<mode>/<format>/<NAME>
  1063	 */
  1064	
  1065	struct uvcg_frame {
  1066		struct config_item	item;
  1067		enum uvcg_format_type	fmt_type;
  1068		struct {
  1069			u8	b_length;
  1070			u8	b_descriptor_type;
  1071			u8	b_descriptor_subtype;
  1072			u8	b_frame_index;
  1073			u8	bm_capabilities;
  1074			u16	w_width;
  1075			u16	w_height;
  1076			u32	dw_min_bit_rate;
  1077			u32	dw_max_bit_rate;
  1078	
  1079			/*
  1080			 * The layout of last three members of framebased frame
  1081			 * is different from uncompressed frame.
  1082			 *   Last three members of uncompressed frame are:
  1083			 *     u32	dw_max_video_frame_buffer_size;
  1084			 *     u32	dw_default_frame_interval;
  1085			 *     u8	b_frame_interval_type;
  1086			 *   Last three members of framebased frame are:
  1087			 *     u32	dw_default_frame_interval;
  1088			 *     u8	b_frame_interval_type;
  1089			 *     u32	dw_bytes_perline;
  1090			 */
> 1091			union {
  1092				u32	dw_max_video_frame_buffer_size;
  1093				u32	dw_bytes_perline;
  1094			};
  1095			u32	dw_default_frame_interval;
  1096			u8	b_frame_interval_type;
  1097		} __attribute__((packed)) frame;
  1098		u32 *dw_frame_interval;
  1099	};
  1100	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org