Hi Jan, I love your patch! Yet something to improve: [auto build test ERROR on axboe-block/for-next] [also build test ERROR on v5.16-rc3 next-20211201] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Jan-Kara/bfq-Fix-use-after-free-with-cgroups/20211201-213549 base: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next config: hexagon-randconfig-r045-20211128 (https://download.01.org/0day-ci/archive/20211202/202112020559.l11FLFdN-lkp@xxxxxxxxx/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 4b553297ef3ee4dc2119d5429adf3072e90fac38) 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/0day-ci/linux/commit/2154a2da8d69308aca6bb431da2d4d9e3e687daa git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Jan-Kara/bfq-Fix-use-after-free-with-cgroups/20211201-213549 git checkout 2154a2da8d69308aca6bb431da2d4d9e3e687daa # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All errors (new ones prefixed by >>): >> block/bfq-iosched.c:5472:46: error: no member named 'children' in 'struct bfq_group' hlist_add_head(&bfqq->children_node, &bfqg->children); ~~~~ ^ 1 error generated. vim +5472 block/bfq-iosched.c 5460 5461 static void bfq_init_bfqq(struct bfq_data *bfqd, struct bfq_group *bfqg, 5462 struct bfq_queue *bfqq, struct bfq_io_cq *bic, 5463 pid_t pid, int is_sync) 5464 { 5465 u64 now_ns = ktime_get_ns(); 5466 5467 RB_CLEAR_NODE(&bfqq->entity.rb_node); 5468 INIT_LIST_HEAD(&bfqq->fifo); 5469 INIT_HLIST_NODE(&bfqq->burst_list_node); 5470 INIT_HLIST_NODE(&bfqq->woken_list_node); 5471 INIT_HLIST_HEAD(&bfqq->woken_list); > 5472 hlist_add_head(&bfqq->children_node, &bfqg->children); 5473 5474 bfqq->ref = 0; 5475 bfqq->bfqd = bfqd; 5476 5477 if (bic) 5478 bfq_set_next_ioprio_data(bfqq, bic); 5479 5480 if (is_sync) { 5481 /* 5482 * No need to mark as has_short_ttime if in 5483 * idle_class, because no device idling is performed 5484 * for queues in idle class 5485 */ 5486 if (!bfq_class_idle(bfqq)) 5487 /* tentatively mark as has_short_ttime */ 5488 bfq_mark_bfqq_has_short_ttime(bfqq); 5489 bfq_mark_bfqq_sync(bfqq); 5490 bfq_mark_bfqq_just_created(bfqq); 5491 } else 5492 bfq_clear_bfqq_sync(bfqq); 5493 5494 /* set end request to minus infinity from now */ 5495 bfqq->ttime.last_end_request = now_ns + 1; 5496 5497 bfqq->creation_time = jiffies; 5498 5499 bfqq->io_start_time = now_ns; 5500 5501 bfq_mark_bfqq_IO_bound(bfqq); 5502 5503 bfqq->pid = pid; 5504 5505 /* Tentative initial value to trade off between thr and lat */ 5506 bfqq->max_budget = (2 * bfq_max_budget(bfqd)) / 3; 5507 bfqq->budget_timeout = bfq_smallest_from_now(); 5508 5509 bfqq->wr_coeff = 1; 5510 bfqq->last_wr_start_finish = jiffies; 5511 bfqq->wr_start_at_switch_to_srt = bfq_smallest_from_now(); 5512 bfqq->split_time = bfq_smallest_from_now(); 5513 5514 /* 5515 * To not forget the possibly high bandwidth consumed by a 5516 * process/queue in the recent past, 5517 * bfq_bfqq_softrt_next_start() returns a value at least equal 5518 * to the current value of bfqq->soft_rt_next_start (see 5519 * comments on bfq_bfqq_softrt_next_start). Set 5520 * soft_rt_next_start to now, to mean that bfqq has consumed 5521 * no bandwidth so far. 5522 */ 5523 bfqq->soft_rt_next_start = jiffies; 5524 5525 /* first request is almost certainly seeky */ 5526 bfqq->seek_history = 1; 5527 } 5528 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx