Hi All, The latest mainline kernel branch fails to build mips decstation_64_defconfig, decstation_defconfig and decstation_r4k_defconfig with the error: kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_new': kernel/bpf/task_iter.c:917:14: error: 'CSS_TASK_ITER_PROCS' undeclared (first use in this function) 917 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED: | ^~~~~~~~~~~~~~~~~~~ kernel/bpf/task_iter.c:917:14: note: each undeclared identifier is reported only once for each function it appears in kernel/bpf/task_iter.c:917:36: error: 'CSS_TASK_ITER_THREADED' undeclared (first use in this function) 917 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED: | ^~~~~~~~~~~~~~~~~~~~~~ kernel/bpf/task_iter.c:925:60: error: invalid application of 'sizeof' to incomplete type 'struct css_task_iter' 925 | kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter)); | ^~~~~~ kernel/bpf/task_iter.c:928:9: error: implicit declaration of function 'css_task_iter_start'; did you mean 'task_seq_start'? [-Werror=implicit-function-declaration] 928 | css_task_iter_start(css, flags, kit->css_it); | ^~~~~~~~~~~~~~~~~~~ | task_seq_start kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_next': kernel/bpf/task_iter.c:938:16: error: implicit declaration of function 'css_task_iter_next'; did you mean 'class_dev_iter_next'? [-Werror=implicit-function-declaration] 938 | return css_task_iter_next(kit->css_it); | ^~~~~~~~~~~~~~~~~~ | class_dev_iter_next kernel/bpf/task_iter.c:938:16: warning: returning 'int' from a function with return type 'struct task_struct *' makes pointer from integer without a cast [-Wint-conversion] 938 | return css_task_iter_next(kit->css_it); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_destroy': kernel/bpf/task_iter.c:947:9: error: implicit declaration of function 'css_task_iter_end' [-Werror=implicit-function-declaration] 947 | css_task_iter_end(kit->css_it); | ^~~~~~~~~~~~~~~~~ git bisect pointed to 9c66dc94b62a ("bpf: Introduce css_task open-coded iterator kfuncs") I will be happy to test any patch or provide any extra log if needed. #regzbot introduced: 9c66dc94b62aef23300f05f63404afb8990920b4 -- Regards Sudip