On Wed, Jun 1, 2022 at 11:17 PM kernel test robot <lkp@xxxxxxxxx> wrote: > > Hi Stanislav, > > Thank you for the patch! Perhaps something to improve: This is a config without CONFIG_BPF_LSM and it makes CGROUP_LSM_START greater than CGROUP_LSM_END (to make sure we don't waste slots on non-CONFIG_BPF_LSM builds) and it screws up (atype >= CGROUP_LSM_START && atype <= CGROUP_LSM_END) check. I'll add an ifdef around that. > [auto build test WARNING on bpf-next/master] > > url: https://github.com/intel-lab-lkp/linux/commits/Stanislav-Fomichev/bpf-cgroup_sock-lsm-flavor/20220602-050600 > base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master > config: i386-randconfig-a004 (https://download.01.org/0day-ci/archive/20220602/202206021403.M9hFZdbY-lkp@xxxxxxxxx/config) > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project b364c76683f8ef241025a9556300778c07b590c2) > 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 > # https://github.com/intel-lab-lkp/linux/commit/584b25fdd30894c312d577f4b6b83f93d64e464b > git remote add linux-review https://github.com/intel-lab-lkp/linux > git fetch --no-tags linux-review Stanislav-Fomichev/bpf-cgroup_sock-lsm-flavor/20220602-050600 > git checkout 584b25fdd30894c312d577f4b6b83f93d64e464b > # save the config file > mkdir build_dir && cp config build_dir/.config > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash kernel/bpf/ > > If you fix the issue, kindly add following tag where applicable > Reported-by: kernel test robot <lkp@xxxxxxxxx> > > All warnings (new ones prefixed by >>): > > >> kernel/bpf/cgroup.c:257:35: warning: overlapping comparisons always evaluate to false [-Wtautological-overlap-compare] > if (atype >= CGROUP_LSM_START && atype <= CGROUP_LSM_END) > ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~ > kernel/bpf/cgroup.c:252:35: warning: overlapping comparisons always evaluate to false [-Wtautological-overlap-compare] > if (atype >= CGROUP_LSM_START && atype <= CGROUP_LSM_END) > ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~ > 2 warnings generated. > > > vim +257 kernel/bpf/cgroup.c > > 226 > 227 /** > 228 * cgroup_bpf_release() - put references of all bpf programs and > 229 * release all cgroup bpf data > 230 * @work: work structure embedded into the cgroup to modify > 231 */ > 232 static void cgroup_bpf_release(struct work_struct *work) > 233 { > 234 struct cgroup *p, *cgrp = container_of(work, struct cgroup, > 235 bpf.release_work); > 236 struct bpf_prog_array *old_array; > 237 struct list_head *storages = &cgrp->bpf.storages; > 238 struct bpf_cgroup_storage *storage, *stmp; > 239 > 240 unsigned int atype; > 241 > 242 mutex_lock(&cgroup_mutex); > 243 > 244 for (atype = 0; atype < ARRAY_SIZE(cgrp->bpf.progs); atype++) { > 245 struct hlist_head *progs = &cgrp->bpf.progs[atype]; > 246 struct bpf_prog_list *pl; > 247 struct hlist_node *pltmp; > 248 > 249 hlist_for_each_entry_safe(pl, pltmp, progs, node) { > 250 hlist_del(&pl->node); > 251 if (pl->prog) { > 252 if (atype >= CGROUP_LSM_START && atype <= CGROUP_LSM_END) > 253 bpf_trampoline_unlink_cgroup_shim(pl->prog); > 254 bpf_prog_put(pl->prog); > 255 } > 256 if (pl->link) { > > 257 if (atype >= CGROUP_LSM_START && atype <= CGROUP_LSM_END) > 258 bpf_trampoline_unlink_cgroup_shim(pl->link->link.prog); > 259 bpf_cgroup_link_auto_detach(pl->link); > 260 } > 261 kfree(pl); > 262 static_branch_dec(&cgroup_bpf_enabled_key[atype]); > 263 } > 264 old_array = rcu_dereference_protected( > 265 cgrp->bpf.effective[atype], > 266 lockdep_is_held(&cgroup_mutex)); > 267 bpf_prog_array_free(old_array); > 268 } > 269 > 270 list_for_each_entry_safe(storage, stmp, storages, list_cg) { > 271 bpf_cgroup_storage_unlink(storage); > 272 bpf_cgroup_storage_free(storage); > 273 } > 274 > 275 mutex_unlock(&cgroup_mutex); > 276 > 277 for (p = cgroup_parent(cgrp); p; p = cgroup_parent(p)) > 278 cgroup_bpf_put(p); > 279 > 280 percpu_ref_exit(&cgrp->bpf.refcnt); > 281 cgroup_put(cgrp); > 282 } > 283 > > -- > 0-DAY CI Kernel Test Service > https://01.org/lkp
