Hi Sean, Thanks for your patch! Perhaps something to improve: [auto build test WARNING on bluetooth-next/master] [also build test WARNING on next-20220211] [cannot apply to v5.17-rc3] [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/sean-wang-mediatek-com/Bluetooth-mt7921s-support-bluetooth-reset-mechanism/20220129-140313 base: https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git master config: riscv-randconfig-c006-20220205 (https://download.01.org/0day-ci/archive/20220213/202202130806.UHxKw5N3-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project dee058c670593b999fec19c458dbbd882ad9de56) 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 riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://github.com/0day-ci/linux/commit/33092fd43b74594bae07555a6fdf15133cc8ec54 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review sean-wang-mediatek-com/Bluetooth-mt7921s-support-bluetooth-reset-mechanism/20220129-140313 git checkout 33092fd43b74594bae07555a6fdf15133cc8ec54 # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=riscv clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <yujie.liu@xxxxxxxxx> clang-analyzer warnings: (new ones prefixed by >>) >> drivers/bluetooth/btusb.c:2273:3: warning: Value stored to 'hdr' is never read [clang-analyzer-deadcode.DeadStores] hdr = (void *)skb->data; ^ ~~~~~~~~~~~~~~~~~ vim +/hdr +2273 drivers/bluetooth/btusb.c 5a87679ffd4436 mark-yw.chen 2021-09-01 2248 a1c49c434e1505 Sean Wang 2019-06-02 2249 static void btusb_mtk_wmt_recv(struct urb *urb) a1c49c434e1505 Sean Wang 2019-06-02 2250 { a1c49c434e1505 Sean Wang 2019-06-02 2251 struct hci_dev *hdev = urb->context; a1c49c434e1505 Sean Wang 2019-06-02 2252 struct btusb_data *data = hci_get_drvdata(hdev); a1c49c434e1505 Sean Wang 2019-06-02 @2253 struct hci_event_hdr *hdr; a1c49c434e1505 Sean Wang 2019-06-02 2254 struct sk_buff *skb; a1c49c434e1505 Sean Wang 2019-06-02 2255 int err; a1c49c434e1505 Sean Wang 2019-06-02 2256 a1c49c434e1505 Sean Wang 2019-06-02 2257 if (urb->status == 0 && urb->actual_length > 0) { a1c49c434e1505 Sean Wang 2019-06-02 2258 hdev->stat.byte_rx += urb->actual_length; a1c49c434e1505 Sean Wang 2019-06-02 2259 a1c49c434e1505 Sean Wang 2019-06-02 2260 /* WMT event shouldn't be fragmented and the size should be a1c49c434e1505 Sean Wang 2019-06-02 2261 * less than HCI_WMT_MAX_EVENT_SIZE. a1c49c434e1505 Sean Wang 2019-06-02 2262 */ a1c49c434e1505 Sean Wang 2019-06-02 2263 skb = bt_skb_alloc(HCI_WMT_MAX_EVENT_SIZE, GFP_ATOMIC); a1c49c434e1505 Sean Wang 2019-06-02 2264 if (!skb) { a1c49c434e1505 Sean Wang 2019-06-02 2265 hdev->stat.err_rx++; 60c6a63a3d3080 Mark-YW.Chen 2021-10-14 2266 kfree(urb->setup_packet); de71a6cb4bf24d Jupeng Zhong 2021-02-02 2267 return; a1c49c434e1505 Sean Wang 2019-06-02 2268 } a1c49c434e1505 Sean Wang 2019-06-02 2269 a1c49c434e1505 Sean Wang 2019-06-02 2270 hci_skb_pkt_type(skb) = HCI_EVENT_PKT; a1c49c434e1505 Sean Wang 2019-06-02 2271 skb_put_data(skb, urb->transfer_buffer, urb->actual_length); a1c49c434e1505 Sean Wang 2019-06-02 2272 a1c49c434e1505 Sean Wang 2019-06-02 @2273 hdr = (void *)skb->data; a1c49c434e1505 Sean Wang 2019-06-02 2274 a1c49c434e1505 Sean Wang 2019-06-02 2275 /* When someone waits for the WMT event, the skb is being cloned a1c49c434e1505 Sean Wang 2019-06-02 2276 * and being processed the events from there then. a1c49c434e1505 Sean Wang 2019-06-02 2277 */ a1c49c434e1505 Sean Wang 2019-06-02 2278 if (test_bit(BTUSB_TX_WAIT_VND_EVT, &data->flags)) { 22cc6b7a1dbb58 Johan Hovold 2019-11-28 2279 data->evt_skb = skb_clone(skb, GFP_ATOMIC); de71a6cb4bf24d Jupeng Zhong 2021-02-02 2280 if (!data->evt_skb) { de71a6cb4bf24d Jupeng Zhong 2021-02-02 2281 kfree_skb(skb); 60c6a63a3d3080 Mark-YW.Chen 2021-10-14 2282 kfree(urb->setup_packet); de71a6cb4bf24d Jupeng Zhong 2021-02-02 2283 return; de71a6cb4bf24d Jupeng Zhong 2021-02-02 2284 } a1c49c434e1505 Sean Wang 2019-06-02 2285 } a1c49c434e1505 Sean Wang 2019-06-02 2286 a1c49c434e1505 Sean Wang 2019-06-02 2287 err = hci_recv_frame(hdev, skb); de71a6cb4bf24d Jupeng Zhong 2021-02-02 2288 if (err < 0) { de71a6cb4bf24d Jupeng Zhong 2021-02-02 2289 kfree_skb(data->evt_skb); de71a6cb4bf24d Jupeng Zhong 2021-02-02 2290 data->evt_skb = NULL; 60c6a63a3d3080 Mark-YW.Chen 2021-10-14 2291 kfree(urb->setup_packet); de71a6cb4bf24d Jupeng Zhong 2021-02-02 2292 return; de71a6cb4bf24d Jupeng Zhong 2021-02-02 2293 } a1c49c434e1505 Sean Wang 2019-06-02 2294 a1c49c434e1505 Sean Wang 2019-06-02 2295 if (test_and_clear_bit(BTUSB_TX_WAIT_VND_EVT, a1c49c434e1505 Sean Wang 2019-06-02 2296 &data->flags)) { a1c49c434e1505 Sean Wang 2019-06-02 2297 /* Barrier to sync with other CPUs */ a1c49c434e1505 Sean Wang 2019-06-02 2298 smp_mb__after_atomic(); a1c49c434e1505 Sean Wang 2019-06-02 2299 wake_up_bit(&data->flags, a1c49c434e1505 Sean Wang 2019-06-02 2300 BTUSB_TX_WAIT_VND_EVT); a1c49c434e1505 Sean Wang 2019-06-02 2301 } 60c6a63a3d3080 Mark-YW.Chen 2021-10-14 2302 kfree(urb->setup_packet); a1c49c434e1505 Sean Wang 2019-06-02 2303 return; a1c49c434e1505 Sean Wang 2019-06-02 2304 } else if (urb->status == -ENOENT) { a1c49c434e1505 Sean Wang 2019-06-02 2305 /* Avoid suspend failed when usb_kill_urb */ a1c49c434e1505 Sean Wang 2019-06-02 2306 return; a1c49c434e1505 Sean Wang 2019-06-02 2307 } a1c49c434e1505 Sean Wang 2019-06-02 2308 a1c49c434e1505 Sean Wang 2019-06-02 2309 usb_mark_last_busy(data->udev); a1c49c434e1505 Sean Wang 2019-06-02 2310 a1c49c434e1505 Sean Wang 2019-06-02 2311 /* The URB complete handler is still called with urb->actual_length = 0 a1c49c434e1505 Sean Wang 2019-06-02 2312 * when the event is not available, so we should keep re-submitting a1c49c434e1505 Sean Wang 2019-06-02 2313 * URB until WMT event returns, Also, It's necessary to wait some time a1c49c434e1505 Sean Wang 2019-06-02 2314 * between the two consecutive control URBs to relax the target device a1c49c434e1505 Sean Wang 2019-06-02 2315 * to generate the event. Otherwise, the WMT event cannot return from a1c49c434e1505 Sean Wang 2019-06-02 2316 * the device successfully. a1c49c434e1505 Sean Wang 2019-06-02 2317 */ 48c13301e6baba Mark Chen 2021-02-02 2318 udelay(500); a1c49c434e1505 Sean Wang 2019-06-02 2319 a1c49c434e1505 Sean Wang 2019-06-02 2320 usb_anchor_urb(urb, &data->ctrl_anchor); a1c49c434e1505 Sean Wang 2019-06-02 2321 err = usb_submit_urb(urb, GFP_ATOMIC); a1c49c434e1505 Sean Wang 2019-06-02 2322 if (err < 0) { 60c6a63a3d3080 Mark-YW.Chen 2021-10-14 2323 kfree(urb->setup_packet); a1c49c434e1505 Sean Wang 2019-06-02 2324 /* -EPERM: urb is being killed; a1c49c434e1505 Sean Wang 2019-06-02 2325 * -ENODEV: device got disconnected a1c49c434e1505 Sean Wang 2019-06-02 2326 */ a1c49c434e1505 Sean Wang 2019-06-02 2327 if (err != -EPERM && err != -ENODEV) a1c49c434e1505 Sean Wang 2019-06-02 2328 bt_dev_err(hdev, "urb %p failed to resubmit (%d)", a1c49c434e1505 Sean Wang 2019-06-02 2329 urb, -err); a1c49c434e1505 Sean Wang 2019-06-02 2330 usb_unanchor_urb(urb); a1c49c434e1505 Sean Wang 2019-06-02 2331 } a1c49c434e1505 Sean Wang 2019-06-02 2332 } a1c49c434e1505 Sean Wang 2019-06-02 2333 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
