<Daniel.Machon@xxxxxxxxxxxxx> writes: >> kernel test robot <lkp@xxxxxxxxx> writes: >> >> > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master >> > head: d8e87774068af213ab5b058b1b114dc397b577aa >> > commit: 6182d5875c330a5a611687caa05f47752455720c [4744/6155] net: dcb: add new apptrust attribute >> > config: i386-buildonly-randconfig-r006-20221107 >> > compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 >> > reproduce (this is a W=1 build): >> > # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=6182d5875c330a5a611687caa05f47752455720c >> > git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git >> > git fetch --no-tags linux-next master >> > git checkout 6182d5875c330a5a611687caa05f47752455720c >> > # save the config file >> > mkdir build_dir && cp config build_dir/.config >> > make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash net/dcb/ >> > >> > If you fix the issue, kindly add following tag where applicable >> > | Reported-by: kernel test robot <lkp@xxxxxxxxx> >> > >> > All warnings (new ones prefixed by >>): >> > >> > net/dcb/dcbnl.c: In function 'dcbnl_ieee_fill': >> >>> net/dcb/dcbnl.c:1230:1: warning: the frame size of 1244 bytes is larger than 1024 bytes [-Wframe-larger-than=] >> >> The on-stack array that was added is pushing things: >> >> > 6182d5875c330a Daniel Machon 2022-11-01 1170 if (ops->dcbnl_getapptrust) { >> > 6182d5875c330a Daniel Machon 2022-11-01 1171 u8 selectors[IEEE_8021QAZ_APP_SEL_MAX + 1] = {0}; >> > 6182d5875c330a Daniel Machon 2022-11-01 1172 int nselectors, i; >> > 6182d5875c330a Daniel Machon 2022-11-01 1173 >> > 6182d5875c330a Daniel Machon 2022-11-01 1174 apptrust = nla_nest_start(skb, DCB_ATTR_DCB_APP_TRUST_TABLE); >> > 6182d5875c330a Daniel Machon 2022-11-01 1175 if (!apptrust) >> > 6182d5875c330a Daniel Machon 2022-11-01 1176 return -EMSGSIZE; >> > 6182d5875c330a Daniel Machon 2022-11-01 1177 >> > 6182d5875c330a Daniel Machon 2022-11-01 1178 err = ops->dcbnl_getapptrust(netdev, selectors, &nselectors); >> > 6182d5875c330a Daniel Machon 2022-11-01 1179 if (!err) { >> > 6182d5875c330a Daniel Machon 2022-11-01 1180 for (i = 0; i < nselectors; i++) { >> > 6182d5875c330a Daniel Machon 2022-11-01 1181 enum ieee_attrs_app type = >> > 6182d5875c330a Daniel Machon 2022-11-01 1182 dcbnl_app_attr_type_get(selectors[i]); >> > 6182d5875c330a Daniel Machon 2022-11-01 1183 err = nla_put_u8(skb, type, selectors[i]); >> > 6182d5875c330a Daniel Machon 2022-11-01 1184 if (err) { >> > 6182d5875c330a Daniel Machon 2022-11-01 1185 nla_nest_cancel(skb, apptrust); >> > 6182d5875c330a Daniel Machon 2022-11-01 1186 return err; >> > 6182d5875c330a Daniel Machon 2022-11-01 1187 } >> > 6182d5875c330a Daniel Machon 2022-11-01 1188 } >> > 6182d5875c330a Daniel Machon 2022-11-01 1189 } >> > 6182d5875c330a Daniel Machon 2022-11-01 1190 >> > 6182d5875c330a Daniel Machon 2022-11-01 1191 nla_nest_end(skb, apptrust); >> > 6182d5875c330a Daniel Machon 2022-11-01 1192 } >> >> I think this should either be converted to dynamic allocation, or the >> array size should be reduced to number of unique selectors, instead of >> the value of the highest selector. > > Yep. Dynamic allocation sounds good to me. Alternatively, could we move > the getapptrust part to a separate noinline function? I think the reasoning behind the warning is that functions with large frames consume too much stack space, which is scarce in kernel. Moving the logic to a separate function might silence the warning, but wouldn't make the issue go away. Extracting the logic to a separate function might still make sense, because it's going to make it easier to manage the dynamic allocation, but is not enough on its own.
