Re: [PATCH bpf-next v4 0/8] Add Open-coded task, css_task and css iters

[Daniel Borkmann <daniel@iogearbox.net>]

On 10/7/23 2:45 PM, Chuyi Zhou wrote:
> Hi,
> 
> This is version 4 of task, css_task and css iters support.
> Thanks for your review!
> 
> --- Changelog ---
> 
> v3 -> v4:https://lore.kernel.org/all/20230925105552.817513-1-zhouchuyi@bytedance.com/
> 
> * Address all the comments from Andrii in patch-3 ~ patch-6
> * Collect Tejun's ack
> * Add a extra patch to rename bpf_iter_task.c to bpf_iter_tasks.c
> * Seperate three BPF program files for selftests (iters_task.c iters_css_task.c iters_css.c)

This fails to build BPF selftests:

[...]
  /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:166:6: error: variable 'skel' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
           if (!ASSERT_OK(err, "setup_cgroup_environment"))
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:190:26: note: uninitialized use occurs here
           iters_css_task__destroy(skel);
                                   ^~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:166:2: note: remove the 'if' if its condition is always false
           if (!ASSERT_OK(err, "setup_cgroup_environment"))
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:162:6: error: variable 'skel' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
           if (!ASSERT_GE(cg_fd, 0, "cg_create"))
     TEST-OBJ [test_progs] xdp.test.o
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:190:26: note: uninitialized use occurs here
           iters_css_task__destroy(skel);
                                   ^~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:162:2: note: remove the 'if' if its condition is always false
           if (!ASSERT_GE(cg_fd, 0, "cg_create"))
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:159:6: error: variable 'skel' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
           if (!ASSERT_OK(err, "setup_cgroup_environment"))
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:190:26: note: uninitialized use occurs here
           iters_css_task__destroy(skel);
                                   ^~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:159:2: note: remove the 'if' if its condition is always false
           if (!ASSERT_OK(err, "setup_cgroup_environment"))
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:154:29: note: initialize the variable 'skel' to silence this warning
           struct iters_css_task *skel;
                                      ^
                                       = NULL
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:213:7: error: variable 'skel' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
                   if (!ASSERT_GE(cgs[i].fd, 0, "cg_create"))
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:244:21: note: uninitialized use occurs here
           iters_css__destroy(skel);
                              ^~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:213:3: note: remove the 'if' if its condition is always false
                   if (!ASSERT_GE(cgs[i].fd, 0, "cg_create"))
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:209:6: error: variable 'skel' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
           if (!ASSERT_OK(err, "setup_cgroup_environment"))
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:244:21: note: uninitialized use occurs here
           iters_css__destroy(skel);
                              ^~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:209:2: note: remove the 'if' if its condition is always false
           if (!ASSERT_OK(err, "setup_cgroup_environment"))
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   /tmp/work/bpf/bpf/tools/testing/selftests/bpf/prog_tests/iters.c:195:24: note: initialize the variable 'skel' to silence this warning
           struct iters_css *skel;
                                 ^
                                  = NULL
   5 errors generated.
   make: *** [Makefile:605: /tmp/work/bpf/bpf/tools/testing/selftests/bpf/iters.test.o] Error 1
   make: *** Waiting for unfinished jobs....
   make: Leaving directory '/tmp/work/bpf/bpf/tools/testing/selftests/bpf'
   Error: Process completed with exit code 2.