CC: kbuild-all(a)lists.01.org TO: "Christian, Gromm," <christian.gromm(a)microchip.com&gt; CC: "Greg Kroah-Hartman" <gregkh(a)linuxfoundation.org&gt; tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: e7b08814b16b80a0bf76eeca16317f8c2ed23b8c commit: 2c069b61a843dc9c3d2296b54c4baa9730286530 [12331/14131] staging: most: usb: return 0 instead of variable :::::: branch date: 2 days ago :::::: commit date: 4 days ago config: x86_64-randconfig-m001-20200531 (attached as .config) compiler: gcc-9 (Debian 9.3.0-13) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; Reported-by: Dan Carpenter <dan.carpenter(a)oracle.com&gt; smatch warnings: drivers/staging/most/usb/usb.c:220 get_stream_frame_size() error: uninitialized symbol 'frame_size'. # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git remote update linux-next git checkout 2c069b61a843dc9c3d2296b54c4baa9730286530 vim +/frame_size +220 drivers/staging/most/usb/usb.c e33269f60ae114 drivers/staging/most/hdm-usb/hdm_usb.c Andrey Shvetsov 2016-10-25 186 a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 187 /** a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 188 * get_stream_frame_size - calculate frame size of current configuration 1c538a417977ec drivers/staging/most/usb/usb.c Christian Gromm 2020-05-27 189 * @dev: device structure a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 190 * @cfg: channel configuration a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 191 */ 1c538a417977ec drivers/staging/most/usb/usb.c Christian Gromm 2020-05-27 192 static unsigned int get_stream_frame_size(struct device *dev, 1c538a417977ec drivers/staging/most/usb/usb.c Christian Gromm 2020-05-27 193 struct most_channel_config *cfg) a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 194 { 2c069b61a843dc drivers/staging/most/usb/usb.c Christian Gromm 2020-05-27 195 unsigned int frame_size; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 196 unsigned int sub_size = cfg->subbuffer_size; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 197 a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 198 if (!sub_size) { 62573221240fdf drivers/staging/most/usb/usb.c Christian Gromm 2020-05-15 199 dev_warn(dev, "Misconfig: Subbuffer size zero.\n"); 2c069b61a843dc drivers/staging/most/usb/usb.c Christian Gromm 2020-05-27 200 return 0; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 201 } a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 202 switch (cfg->data_type) { 0540609fe217c3 drivers/staging/most/hdm-usb/hdm_usb.c Andrey Shvetsov 2016-09-21 203 case MOST_CH_ISOC: a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 204 frame_size = AV_PACKETS_PER_XACT * sub_size; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 205 break; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 206 case MOST_CH_SYNC: a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 207 if (cfg->packets_per_xact == 0) { 62573221240fdf drivers/staging/most/usb/usb.c Christian Gromm 2020-05-15 208 dev_warn(dev, "Misconfig: Packets per XACT zero\n"); a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 209 frame_size = 0; 9deba73de56ce5 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-10-21 210 } else if (cfg->packets_per_xact == 0xFF) { a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 211 frame_size = (USB_MTU / sub_size) * sub_size; 9deba73de56ce5 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-10-21 212 } else { a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 213 frame_size = cfg->packets_per_xact * sub_size; 9deba73de56ce5 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-10-21 214 } a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 215 break; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 216 default: 62573221240fdf drivers/staging/most/usb/usb.c Christian Gromm 2020-05-15 217 dev_warn(dev, "Query frame size of non-streaming channel\n"); a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 218 break; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 219 } a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 @220 return frame_size; a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 221 } a4198cdf0c3460 drivers/staging/most/hdm-usb/hdm_usb.c Christian Gromm 2015-07-24 222 :::::: The code at line 220 was first introduced by commit :::::: a4198cdf0c3460d767d0d36979cd633021c127a2 Staging: most: add MOST driver's hdm-usb module :::::: TO: Christian Gromm <christian.gromm(a)microchip.com&gt; :::::: CC: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org