Hi Hongyu, kernel test robot noticed the following build warnings: [auto build test WARNING on next-20230601] url: https://github.com/intel-lab-lkp/linux/commits/Hongyu-Xie/tty-serial-add-panic-serial-helper/20230602-092109 base: next-20230601 patch link: https://lore.kernel.org/r/20230602011835.582430-1-xiehongyu1%40kylinos.cn patch subject: [PATCH v2 -next] tty: serial: add panic serial helper reproduce: # https://github.com/intel-lab-lkp/linux/commit/0d2aa58f592716807757b3c92fb62fe7aa4eef66 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Hongyu-Xie/tty-serial-add-panic-serial-helper/20230602-092109 git checkout 0d2aa58f592716807757b3c92fb62fe7aa4eef66 make menuconfig # enable CONFIG_COMPILE_TEST, CONFIG_WARN_MISSING_DOCUMENTS, CONFIG_WARN_ABI_ERRORS make htmldocs If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202306040839.IrnnKYxH-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> Documentation/dev-tools/panic_serial_helper.rst:66: WARNING: Unexpected indentation. >> Documentation/dev-tools/panic_serial_helper.rst:62: WARNING: Inline interpreted text or phrase reference start-string without end-string. >> Documentation/dev-tools/panic_serial_helper.rst:69: WARNING: Block quote ends without a blank line; unexpected unindent. >> Documentation/dev-tools/panic_serial_helper.rst:86: WARNING: Enumerated list ends without a blank line; unexpected unindent. >> Documentation/dev-tools/panic_serial_helper.rst:92: WARNING: Option list ends without a blank line; unexpected unindent. >> Documentation/dev-tools/panic_serial_helper.rst:130: WARNING: Inconsistent literal block quoting. vim +66 Documentation/dev-tools/panic_serial_helper.rst 61 > 62 First you need to enable ``CONFIG_PANIC_SERIAL_HELPER`` in your 63 config. To enable ``CONFIG_PANIC_SERIAL_HELPER`` you should look under 64 :menuselection: 65 `Device Drivers > 66 --> Character devices 67 --> Enable TTY (TTY [=y]) 68 --> Serial drivers` > 69 and select 70 :menuselection:`debug through UART after panic`. 71 72 Second, build and update the kernel image. Then wait for panic. 73 74 After panic, you need to do the following, 75 1. connect the UART side of an USB-to-UART tool to any UART 76 port on your device (PC, server, Laptop, etc...). 77 Connect the USB side of that tool to another PC. Open 78 minicom (or other app) on that PC, and set "/dev/ttyUSB0"(or 79 "/dev/ttyUSB1 if there is already another USB-to-UART tool 80 connected to your device) with "115200 8N1". 81 82 It automatically selects the port where you first press the 83 "Enter" key (some keyboard labeled this with "Return"). 84 85 2. press "Enter" (or "Return") in that > 86 minicom window; you'll get a help menu: 87 " 88 help: 89 -a show all kernel msg 90 -3 show S3 msg 91 -4 show S4 msg > 92 -filter-[string] show msg containing [string] 93 -q- quit 94 " 95 96 see ``Help menu options`` for details. 97 98 3. finally, type 'a', '3', '4', 'q' or "filter-xxx" then press 99 "Enter" to get what you want. 100 101 Help menu options 102 ----------------- 103 Available options: 104 105 - a 106 107 Show all the messages starting from ``Booting Linux on ...`` 108 109 - 3 110 111 If STR happened before panic, this will show messages starting from 112 ``PM: suspend entry...`` 113 114 - 4 115 116 If STD happened before panic, this will show messages starting from 117 ``PM: hibernation entry...`` 118 119 - filter-[string] 120 121 Provide case-ignored filter matching. Only show messages that containing 122 ``string``. For example, if you're only interesting in message lines 123 that containing ``CPU`` or ``cpu``, you just input 124 ``filter-CPU`` or ``filter-cpu``. 125 Here is an output example for filtering ``CPU``:: 126 127 <6>[ 0.000000] Booting Linux on physical CPU 0x0000000000 [0x701f6633 128 <6>[ 0.000000] Detected PIPT I-cache on CPU0 129 <6>[ 0.000000] CPU features: detected: Kernel page table isolation (K > 130 ... -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki