Hi Sherry, https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Sherry-Sun/tty-serdev-serdev-ttyport-add-devt-for-ctrl-dev/20230315-185913 base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing patch link: https://lore.kernel.org/r/20230315105400.23426-1-sherry.sun%40nxp.com patch subject: [PATCH] tty: serdev: serdev-ttyport: add devt for ctrl->dev config: x86_64-randconfig-m001 (https://download.01.org/0day-ci/archive/20230316/202303160201.bnmM2caW-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <error27@xxxxxxxxx> | Link: https://lore.kernel.org/r/202303160201.bnmM2caW-lkp@xxxxxxxxx/ smatch warnings: drivers/tty/serdev/serdev-ttyport.c:273 serdev_tty_port_register() warn: variable dereferenced before check 'drv' (see line 270) vim +/drv +273 drivers/tty/serdev/serdev-ttyport.c bed35c6dfa6a36 Rob Herring 2017-02-02 264 struct device *serdev_tty_port_register(struct tty_port *port, bed35c6dfa6a36 Rob Herring 2017-02-02 265 struct device *parent, bed35c6dfa6a36 Rob Herring 2017-02-02 266 struct tty_driver *drv, int idx) bed35c6dfa6a36 Rob Herring 2017-02-02 267 { bed35c6dfa6a36 Rob Herring 2017-02-02 268 struct serdev_controller *ctrl; bed35c6dfa6a36 Rob Herring 2017-02-02 269 struct serport *serport; 225acc66b125b9 Sherry Sun 2023-03-15 @270 dev_t devt = MKDEV(drv->major, drv->minor_start) + idx; ^^^^^ ^^^^^ Dereferences. bed35c6dfa6a36 Rob Herring 2017-02-02 271 int ret; bed35c6dfa6a36 Rob Herring 2017-02-02 272 bed35c6dfa6a36 Rob Herring 2017-02-02 @273 if (!port || !drv || !parent) ^^^^ Checked too late. Are these checks really required? bed35c6dfa6a36 Rob Herring 2017-02-02 274 return ERR_PTR(-ENODEV); bed35c6dfa6a36 Rob Herring 2017-02-02 275 bed35c6dfa6a36 Rob Herring 2017-02-02 276 ctrl = serdev_controller_alloc(parent, sizeof(struct serport)); bed35c6dfa6a36 Rob Herring 2017-02-02 277 if (!ctrl) bed35c6dfa6a36 Rob Herring 2017-02-02 278 return ERR_PTR(-ENOMEM); bed35c6dfa6a36 Rob Herring 2017-02-02 279 serport = serdev_controller_get_drvdata(ctrl); bed35c6dfa6a36 Rob Herring 2017-02-02 280 bed35c6dfa6a36 Rob Herring 2017-02-02 281 serport->port = port; bed35c6dfa6a36 Rob Herring 2017-02-02 282 serport->tty_idx = idx; bed35c6dfa6a36 Rob Herring 2017-02-02 283 serport->tty_drv = drv; bed35c6dfa6a36 Rob Herring 2017-02-02 284 225acc66b125b9 Sherry Sun 2023-03-15 285 ctrl->dev.devt = devt; bed35c6dfa6a36 Rob Herring 2017-02-02 286 ctrl->ops = &ctrl_ops; bed35c6dfa6a36 Rob Herring 2017-02-02 287 aee5da7838787f Johan Hovold 2017-04-11 288 port->client_ops = &client_ops; aee5da7838787f Johan Hovold 2017-04-11 289 port->client_data = ctrl; aee5da7838787f Johan Hovold 2017-04-11 290 bed35c6dfa6a36 Rob Herring 2017-02-02 291 ret = serdev_controller_add(ctrl); bed35c6dfa6a36 Rob Herring 2017-02-02 292 if (ret) aee5da7838787f Johan Hovold 2017-04-11 293 goto err_reset_data; bed35c6dfa6a36 Rob Herring 2017-02-02 294 bed35c6dfa6a36 Rob Herring 2017-02-02 295 dev_info(&ctrl->dev, "tty port %s%d registered\n", drv->name, idx); bed35c6dfa6a36 Rob Herring 2017-02-02 296 return &ctrl->dev; bed35c6dfa6a36 Rob Herring 2017-02-02 297 aee5da7838787f Johan Hovold 2017-04-11 298 err_reset_data: aee5da7838787f Johan Hovold 2017-04-11 299 port->client_data = NULL; 0c5aae59270fb1 Johan Hovold 2020-02-10 300 port->client_ops = &tty_port_default_client_ops; bed35c6dfa6a36 Rob Herring 2017-02-02 301 serdev_controller_put(ctrl); aee5da7838787f Johan Hovold 2017-04-11 302 bed35c6dfa6a36 Rob Herring 2017-02-02 303 return ERR_PTR(ret); bed35c6dfa6a36 Rob Herring 2017-02-02 304 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
