mainline build failure due to 9c66dc94b62a ("bpf: Introduce css_task open-coded iterator kfuncs")

[Chuyi Zhou]

Hello,

在 2023/11/2 16:50, Sudip Mukherjee (Codethink) 写道:
> 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

Thanks for the report! This issue has been solved by Jiri.[1]

[1]:https://lore.kernel.org/all/169890482505.9002.10852784674164703819.git-patchwork-notify@xxxxxxxxxx/