Hi Samuel, Thank you for the patch! Yet something to improve: [auto build test ERROR on next-20200507] [also build test ERROR on dm/for-next] [cannot apply to v5.7-rc4] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Samuel-Zou/dm-mpath-Remove-unused-variable-ret/20200508-031551 base: 6b43f715b6379433e8eb30aa9bcc99bd6a585f77 config: alpha-allyesconfig (attached as .config) compiler: alpha-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day GCC_VERSION=9.3.0 make.cross ARCH=alpha If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot All error/warnings (new ones prefixed by >>): In file included from drivers/md/dm.h:14, from drivers/md/dm-historical-service-time.c:24: drivers/md/dm-historical-service-time.c: In function 'hst_status': >> include/linux/device-mapper.h:570:22: error: 'sz' undeclared (first use in this function); did you mean 's'? 570 | #define DMEMIT(x...) sz += ((sz >= maxlen) ? \ | ^~ >> drivers/md/dm-historical-service-time.c:245:3: note: in expansion of macro 'DMEMIT' 245 | DMEMIT("2 %u %u ", s->weights[0], s->threshold_multiplier); | ^~~~~~ include/linux/device-mapper.h:570:22: note: each undeclared identifier is reported only once for each function it appears in 570 | #define DMEMIT(x...) sz += ((sz >= maxlen) ? \ | ^~ >> drivers/md/dm-historical-service-time.c:245:3: note: in expansion of macro 'DMEMIT' 245 | DMEMIT("2 %u %u ", s->weights[0], s->threshold_multiplier); | ^~~~~~ vim +/DMEMIT +245 drivers/md/dm-historical-service-time.c 580d206a4321a1 Khazhismel Kumykov 2020-04-30 236 580d206a4321a1 Khazhismel Kumykov 2020-04-30 237 static int hst_status(struct path_selector *ps, struct dm_path *path, 580d206a4321a1 Khazhismel Kumykov 2020-04-30 238 status_type_t type, char *result, unsigned int maxlen) 580d206a4321a1 Khazhismel Kumykov 2020-04-30 239 { 580d206a4321a1 Khazhismel Kumykov 2020-04-30 240 struct path_info *pi; 580d206a4321a1 Khazhismel Kumykov 2020-04-30 241 580d206a4321a1 Khazhismel Kumykov 2020-04-30 242 if (!path) { 580d206a4321a1 Khazhismel Kumykov 2020-04-30 243 struct selector *s = ps->context; 580d206a4321a1 Khazhismel Kumykov 2020-04-30 244 580d206a4321a1 Khazhismel Kumykov 2020-04-30 @245 DMEMIT("2 %u %u ", s->weights[0], s->threshold_multiplier); 580d206a4321a1 Khazhismel Kumykov 2020-04-30 246 } else { 580d206a4321a1 Khazhismel Kumykov 2020-04-30 247 pi = path->pscontext; 580d206a4321a1 Khazhismel Kumykov 2020-04-30 248 580d206a4321a1 Khazhismel Kumykov 2020-04-30 249 switch (type) { 580d206a4321a1 Khazhismel Kumykov 2020-04-30 250 case STATUSTYPE_INFO: 580d206a4321a1 Khazhismel Kumykov 2020-04-30 251 DMEMIT("%llu %llu %llu ", pi->historical_service_time, 580d206a4321a1 Khazhismel Kumykov 2020-04-30 252 pi->outstanding, pi->stale_after); 580d206a4321a1 Khazhismel Kumykov 2020-04-30 253 break; 580d206a4321a1 Khazhismel Kumykov 2020-04-30 254 case STATUSTYPE_TABLE: 580d206a4321a1 Khazhismel Kumykov 2020-04-30 255 DMEMIT("0 "); 580d206a4321a1 Khazhismel Kumykov 2020-04-30 256 break; 580d206a4321a1 Khazhismel Kumykov 2020-04-30 257 } 580d206a4321a1 Khazhismel Kumykov 2020-04-30 258 } 580d206a4321a1 Khazhismel Kumykov 2020-04-30 259 356072d04813ba Samuel Zou 2020-05-07 260 return 0; 580d206a4321a1 Khazhismel Kumykov 2020-04-30 261 } 580d206a4321a1 Khazhismel Kumykov 2020-04-30 262 :::::: The code at line 245 was first introduced by commit :::::: 580d206a4321a146ef4637f14f2fc6d0d5c72c12 dm mpath: add Historical Service Time Path Selector :::::: TO: Khazhismel Kumykov :::::: CC: Mike Snitzer --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org