Hi Oliver, I love your patch! Perhaps something to improve: [auto build test WARNING on media-tree/master] [also build test WARNING on v5.18-rc7 next-20220517] [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/intel-lab-lkp/linux/commits/Oliver-Neukum/airspy-respect-the-DMA-coherency-rules/20220517-191203 base: git://linuxtv.org/media_tree.git master config: i386-randconfig-a006-20220516 (https://download.01.org/0day-ci/archive/20220518/202205180516.aJrehmYZ-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 853fa8ee225edf2d0de94b0dcbd31bea916e825e) 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 # https://github.com/intel-lab-lkp/linux/commit/1001f475c1972ae2ab2be36a64d723f12c56786d git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Oliver-Neukum/airspy-respect-the-DMA-coherency-rules/20220517-191203 git checkout 1001f475c1972ae2ab2be36a64d723f12c56786d # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/media/usb/airspy/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/media/usb/airspy/airspy.c:979:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (!buf) ^~~~ drivers/media/usb/airspy/airspy.c:1082:9: note: uninitialized use occurs here return ret; ^~~ drivers/media/usb/airspy/airspy.c:979:2: note: remove the 'if' if its condition is always false if (!buf) ^~~~~~~~~ drivers/media/usb/airspy/airspy.c:976:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] if (!s->buf) ^~~~~~~ drivers/media/usb/airspy/airspy.c:1082:9: note: uninitialized use occurs here return ret; ^~~ drivers/media/usb/airspy/airspy.c:976:2: note: remove the 'if' if its condition is always false if (!s->buf) ^~~~~~~~~~~~ drivers/media/usb/airspy/airspy.c:966:9: note: initialize the variable 'ret' to silence this warning int ret; ^ = 0 2 warnings generated. vim +979 drivers/media/usb/airspy/airspy.c 961 962 static int airspy_probe(struct usb_interface *intf, 963 const struct usb_device_id *id) 964 { 965 struct airspy *s; 966 int ret; 967 u8 u8tmp, *buf = NULL; 968 969 s = kzalloc(sizeof(struct airspy), GFP_KERNEL); 970 if (s == NULL) { 971 dev_err(&intf->dev, "Could not allocate memory for state\n"); 972 return -ENOMEM; 973 } 974 975 s->buf = kzalloc(BUF_SIZE, GFP_KERNEL); 976 if (!s->buf) 977 goto err_free_mem; 978 buf = kzalloc(BUF_SIZE, GFP_KERNEL); > 979 if (!buf) 980 goto err_free_mem; 981 982 mutex_init(&s->v4l2_lock); 983 mutex_init(&s->vb_queue_lock); 984 spin_lock_init(&s->queued_bufs_lock); 985 INIT_LIST_HEAD(&s->queued_bufs); 986 s->dev = &intf->dev; 987 s->udev = interface_to_usbdev(intf); 988 s->f_adc = bands[0].rangelow; 989 s->f_rf = bands_rf[0].rangelow; 990 s->pixelformat = formats[0].pixelformat; 991 s->buffersize = formats[0].buffersize; 992 993 /* Detect device */ 994 ret = airspy_ctrl_msg(s, CMD_BOARD_ID_READ, 0, 0, &u8tmp, 1); 995 if (ret == 0) 996 ret = airspy_ctrl_msg(s, CMD_VERSION_STRING_READ, 0, 0, 997 buf, BUF_SIZE); 998 if (ret) { 999 dev_err(s->dev, "Could not detect board\n"); 1000 goto err_free_mem; 1001 } 1002 1003 buf[BUF_SIZE - 1] = '\0'; 1004 1005 dev_info(s->dev, "Board ID: %02x\n", u8tmp); 1006 dev_info(s->dev, "Firmware version: %s\n", buf); 1007 1008 /* Init videobuf2 queue structure */ 1009 s->vb_queue.type = V4L2_BUF_TYPE_SDR_CAPTURE; 1010 s->vb_queue.io_modes = VB2_MMAP | VB2_USERPTR | VB2_READ; 1011 s->vb_queue.drv_priv = s; 1012 s->vb_queue.buf_struct_size = sizeof(struct airspy_frame_buf); 1013 s->vb_queue.ops = &airspy_vb2_ops; 1014 s->vb_queue.mem_ops = &vb2_vmalloc_memops; 1015 s->vb_queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC; 1016 ret = vb2_queue_init(&s->vb_queue); 1017 if (ret) { 1018 dev_err(s->dev, "Could not initialize vb2 queue\n"); 1019 goto err_free_mem; 1020 } 1021 1022 /* Init video_device structure */ 1023 s->vdev = airspy_template; 1024 s->vdev.queue = &s->vb_queue; 1025 s->vdev.queue->lock = &s->vb_queue_lock; 1026 video_set_drvdata(&s->vdev, s); 1027 1028 /* Register the v4l2_device structure */ 1029 s->v4l2_dev.release = airspy_video_release; 1030 ret = v4l2_device_register(&intf->dev, &s->v4l2_dev); 1031 if (ret) { 1032 dev_err(s->dev, "Failed to register v4l2-device (%d)\n", ret); 1033 goto err_free_mem; 1034 } 1035 1036 /* Register controls */ 1037 v4l2_ctrl_handler_init(&s->hdl, 5); 1038 s->lna_gain_auto = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops, 1039 V4L2_CID_RF_TUNER_LNA_GAIN_AUTO, 0, 1, 1, 0); 1040 s->lna_gain = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops, 1041 V4L2_CID_RF_TUNER_LNA_GAIN, 0, 14, 1, 8); 1042 v4l2_ctrl_auto_cluster(2, &s->lna_gain_auto, 0, false); 1043 s->mixer_gain_auto = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops, 1044 V4L2_CID_RF_TUNER_MIXER_GAIN_AUTO, 0, 1, 1, 0); 1045 s->mixer_gain = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops, 1046 V4L2_CID_RF_TUNER_MIXER_GAIN, 0, 15, 1, 8); 1047 v4l2_ctrl_auto_cluster(2, &s->mixer_gain_auto, 0, false); 1048 s->if_gain = v4l2_ctrl_new_std(&s->hdl, &airspy_ctrl_ops, 1049 V4L2_CID_RF_TUNER_IF_GAIN, 0, 15, 1, 0); 1050 if (s->hdl.error) { 1051 ret = s->hdl.error; 1052 dev_err(s->dev, "Could not initialize controls\n"); 1053 goto err_free_controls; 1054 } 1055 1056 v4l2_ctrl_handler_setup(&s->hdl); 1057 1058 s->v4l2_dev.ctrl_handler = &s->hdl; 1059 s->vdev.v4l2_dev = &s->v4l2_dev; 1060 s->vdev.lock = &s->v4l2_lock; 1061 s->vdev.device_caps = V4L2_CAP_SDR_CAPTURE | V4L2_CAP_STREAMING | 1062 V4L2_CAP_READWRITE | V4L2_CAP_TUNER; 1063 1064 ret = video_register_device(&s->vdev, VFL_TYPE_SDR, -1); 1065 if (ret) { 1066 dev_err(s->dev, "Failed to register as video device (%d)\n", 1067 ret); 1068 goto err_free_controls; 1069 } 1070 dev_info(s->dev, "Registered as %s\n", 1071 video_device_node_name(&s->vdev)); 1072 dev_notice(s->dev, "SDR API is still slightly experimental and functionality changes may follow\n"); 1073 return 0; 1074 1075 err_free_controls: 1076 v4l2_ctrl_handler_free(&s->hdl); 1077 v4l2_device_unregister(&s->v4l2_dev); 1078 err_free_mem: 1079 kfree(buf); 1080 kfree(s->buf); 1081 kfree(s); 1082 return ret; 1083 } 1084 -- 0-DAY CI Kernel Test Service https://01.org/lkp
