From: Matthieu Baerts <[email protected]>
Our MPTCP CI complained [1] -- and KBuild too -- that it was no longer
possible to build the kernel without CONFIG_CGROUPS:
kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_new':
kernel/bpf/task_iter.c:919:14: error: 'CSS_TASK_ITER_PROCS' undeclared (first use in this function)
919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
| ^~~~~~~~~~~~~~~~~~~
kernel/bpf/task_iter.c:919:14: note: each undeclared identifier is reported only once for each function it appears in
kernel/bpf/task_iter.c:919:36: error: 'CSS_TASK_ITER_THREADED' undeclared (first use in this function)
919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
| ^~~~~~~~~~~~~~~~~~~~~~
kernel/bpf/task_iter.c:927:60: error: invalid application of 'sizeof' to incomplete type 'struct css_task_iter'
927 | kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter));
| ^~~~~~
kernel/bpf/task_iter.c:930:9: error: implicit declaration of function 'css_task_iter_start'; did you mean 'task_seq_start'? [-Werror=implicit-function-declaration]
930 | 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:940:16: error: implicit declaration of function 'css_task_iter_next'; did you mean 'class_dev_iter_next'? [-Werror=implicit-function-declaration]
940 | return css_task_iter_next(kit->css_it);
| ^~~~~~~~~~~~~~~~~~
| class_dev_iter_next
kernel/bpf/task_iter.c:940:16: error: returning 'int' from a function with return type 'struct task_struct *' makes pointer from integer without a cast [-Werror=int-conversion]
940 | 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:949:9: error: implicit declaration of function 'css_task_iter_end' [-Werror=implicit-function-declaration]
949 | css_task_iter_end(kit->css_it);
| ^~~~~~~~~~~~~~~~~
This patch simply surrounds with a #ifdef the new code requiring CGroups
support. It seems enough for the compiler and this is similar to
bpf_iter_css_{new,next,destroy}() functions where no other #ifdef have
been added in kernel/bpf/helpers.c and in the selftests.
Fixes: 9c66dc94b62a ("bpf: Introduce css_task open-coded iterator kfuncs")
Link: https://github.com/multipath-tcp/mptcp_net-next/actions/runs/6665206927
Reported-by: kernel test robot <[email protected]>
Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
Signed-off-by: Matthieu Baerts <[email protected]>
[ added missing ifdefs for BTF_ID cgroup definitions ]
Signed-off-by: Jiri Olsa <[email protected]>
---
kernel/bpf/helpers.c | 8 +++++---
kernel/bpf/task_iter.c | 4 ++++
kernel/bpf/verifier.c | 8 ++++++++
3 files changed, 17 insertions(+), 3 deletions(-)
diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c
index e46ac288a108..95449ea7cc1b 100644
--- a/kernel/bpf/helpers.c
+++ b/kernel/bpf/helpers.c
@@ -2564,15 +2564,17 @@ BTF_ID_FLAGS(func, bpf_iter_num_destroy, KF_ITER_DESTROY)
BTF_ID_FLAGS(func, bpf_iter_task_vma_new, KF_ITER_NEW | KF_RCU)
BTF_ID_FLAGS(func, bpf_iter_task_vma_next, KF_ITER_NEXT | KF_RET_NULL)
BTF_ID_FLAGS(func, bpf_iter_task_vma_destroy, KF_ITER_DESTROY)
+#ifdef CONFIG_CGROUPS
BTF_ID_FLAGS(func, bpf_iter_css_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS)
BTF_ID_FLAGS(func, bpf_iter_css_task_next, KF_ITER_NEXT | KF_RET_NULL)
BTF_ID_FLAGS(func, bpf_iter_css_task_destroy, KF_ITER_DESTROY)
-BTF_ID_FLAGS(func, bpf_iter_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED)
-BTF_ID_FLAGS(func, bpf_iter_task_next, KF_ITER_NEXT | KF_RET_NULL)
-BTF_ID_FLAGS(func, bpf_iter_task_destroy, KF_ITER_DESTROY)
BTF_ID_FLAGS(func, bpf_iter_css_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED)
BTF_ID_FLAGS(func, bpf_iter_css_next, KF_ITER_NEXT | KF_RET_NULL)
BTF_ID_FLAGS(func, bpf_iter_css_destroy, KF_ITER_DESTROY)
+#endif
+BTF_ID_FLAGS(func, bpf_iter_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED)
+BTF_ID_FLAGS(func, bpf_iter_task_next, KF_ITER_NEXT | KF_RET_NULL)
+BTF_ID_FLAGS(func, bpf_iter_task_destroy, KF_ITER_DESTROY)
BTF_ID_FLAGS(func, bpf_dynptr_adjust)
BTF_ID_FLAGS(func, bpf_dynptr_is_null)
BTF_ID_FLAGS(func, bpf_dynptr_is_rdonly)
diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c
index 59e747938bdb..e0d313114a5b 100644
--- a/kernel/bpf/task_iter.c
+++ b/kernel/bpf/task_iter.c
@@ -894,6 +894,8 @@ __bpf_kfunc void bpf_iter_task_vma_destroy(struct bpf_iter_task_vma *it)
__diag_pop();
+#ifdef CONFIG_CGROUPS
+
struct bpf_iter_css_task {
__u64 __opaque[1];
} __attribute__((aligned(8)));
@@ -952,6 +954,8 @@ __bpf_kfunc void bpf_iter_css_task_destroy(struct bpf_iter_css_task *it)
__diag_pop();
+#endif /* CONFIG_CGROUPS */
+
struct bpf_iter_task {
__u64 __opaque[3];
} __attribute__((aligned(8)));
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index e42ce974b106..f2afb17a1534 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -5421,7 +5421,9 @@ static bool in_rcu_cs(struct bpf_verifier_env *env)
/* Once GCC supports btf_type_tag the following mechanism will be replaced with tag check */
BTF_SET_START(rcu_protected_types)
BTF_ID(struct, prog_test_ref_kfunc)
+#ifdef CONFIG_CGROUPS
BTF_ID(struct, cgroup)
+#endif
BTF_ID(struct, bpf_cpumask)
BTF_ID(struct, task_struct)
BTF_SET_END(rcu_protected_types)
@@ -10873,7 +10875,9 @@ BTF_ID(func, bpf_dynptr_clone)
BTF_ID(func, bpf_percpu_obj_new_impl)
BTF_ID(func, bpf_percpu_obj_drop_impl)
BTF_ID(func, bpf_throw)
+#ifdef CONFIG_CGROUPS
BTF_ID(func, bpf_iter_css_task_new)
+#endif
BTF_SET_END(special_kfunc_set)
BTF_ID_LIST(special_kfunc_list)
@@ -10899,7 +10903,11 @@ BTF_ID(func, bpf_dynptr_clone)
BTF_ID(func, bpf_percpu_obj_new_impl)
BTF_ID(func, bpf_percpu_obj_drop_impl)
BTF_ID(func, bpf_throw)
+#ifdef CONFIG_CGROUPS
BTF_ID(func, bpf_iter_css_task_new)
+#else
+BTF_ID_UNUSED
+#endif
static bool is_kfunc_ret_null(struct bpf_kfunc_call_arg_meta *meta)
{
--
2.41.0
Hello:
This patch was applied to bpf/bpf.git (master)
by Alexei Starovoitov <[email protected]>:
On Wed, 1 Nov 2023 19:16:01 +0100 you wrote:
> From: Matthieu Baerts <[email protected]>
>
> Our MPTCP CI complained [1] -- and KBuild too -- that it was no longer
> possible to build the kernel without CONFIG_CGROUPS:
>
> kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_new':
> kernel/bpf/task_iter.c:919:14: error: 'CSS_TASK_ITER_PROCS' undeclared (first use in this function)
> 919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
> | ^~~~~~~~~~~~~~~~~~~
> kernel/bpf/task_iter.c:919:14: note: each undeclared identifier is reported only once for each function it appears in
> kernel/bpf/task_iter.c:919:36: error: 'CSS_TASK_ITER_THREADED' undeclared (first use in this function)
> 919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
> | ^~~~~~~~~~~~~~~~~~~~~~
> kernel/bpf/task_iter.c:927:60: error: invalid application of 'sizeof' to incomplete type 'struct css_task_iter'
> 927 | kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter));
> | ^~~~~~
> kernel/bpf/task_iter.c:930:9: error: implicit declaration of function 'css_task_iter_start'; did you mean 'task_seq_start'? [-Werror=implicit-function-declaration]
> 930 | 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:940:16: error: implicit declaration of function 'css_task_iter_next'; did you mean 'class_dev_iter_next'? [-Werror=implicit-function-declaration]
> 940 | return css_task_iter_next(kit->css_it);
> | ^~~~~~~~~~~~~~~~~~
> | class_dev_iter_next
> kernel/bpf/task_iter.c:940:16: error: returning 'int' from a function with return type 'struct task_struct *' makes pointer from integer without a cast [-Werror=int-conversion]
> 940 | 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:949:9: error: implicit declaration of function 'css_task_iter_end' [-Werror=implicit-function-declaration]
> 949 | css_task_iter_end(kit->css_it);
> | ^~~~~~~~~~~~~~~~~
>
> [...]
Here is the summary with links:
- [PATCHv2,bpf-next] bpf: fix compilation error without CGROUPS
https://git.kernel.org/bpf/bpf/c/05670f81d128
You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html
On Wed, Nov 1, 2023 at 7:16 PM Jiri Olsa <[email protected]> wrote:
> From: Matthieu Baerts <[email protected]>
> Our MPTCP CI complained [1] -- and KBuild too -- that it was no longer
> possible to build the kernel without CONFIG_CGROUPS:
>
> kernel/bpf/task_iter.c: In function 'bpf_iter_css_task_new':
> kernel/bpf/task_iter.c:919:14: error: 'CSS_TASK_ITER_PROCS' undeclared (first use in this function)
> 919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
> | ^~~~~~~~~~~~~~~~~~~
> kernel/bpf/task_iter.c:919:14: note: each undeclared identifier is reported only once for each function it appears in
> kernel/bpf/task_iter.c:919:36: error: 'CSS_TASK_ITER_THREADED' undeclared (first use in this function)
> 919 | case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED:
> | ^~~~~~~~~~~~~~~~~~~~~~
> kernel/bpf/task_iter.c:927:60: error: invalid application of 'sizeof' to incomplete type 'struct css_task_iter'
> 927 | kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter));
> | ^~~~~~
> kernel/bpf/task_iter.c:930:9: error: implicit declaration of function 'css_task_iter_start'; did you mean 'task_seq_start'? [-Werror=implicit-function-declaration]
> 930 | 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:940:16: error: implicit declaration of function 'css_task_iter_next'; did you mean 'class_dev_iter_next'? [-Werror=implicit-function-declaration]
> 940 | return css_task_iter_next(kit->css_it);
> | ^~~~~~~~~~~~~~~~~~
> | class_dev_iter_next
> kernel/bpf/task_iter.c:940:16: error: returning 'int' from a function with return type 'struct task_struct *' makes pointer from integer without a cast [-Werror=int-conversion]
> 940 | 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:949:9: error: implicit declaration of function 'css_task_iter_end' [-Werror=implicit-function-declaration]
> 949 | css_task_iter_end(kit->css_it);
> | ^~~~~~~~~~~~~~~~~
>
> This patch simply surrounds with a #ifdef the new code requiring CGroups
> support. It seems enough for the compiler and this is similar to
> bpf_iter_css_{new,next,destroy}() functions where no other #ifdef have
> been added in kernel/bpf/helpers.c and in the selftests.
>
> Fixes: 9c66dc94b62a ("bpf: Introduce css_task open-coded iterator kfuncs")
> Link: https://github.com/multipath-tcp/mptcp_net-next/actions/runs/6665206927
> Reported-by: kernel test robot <[email protected]>
> Closes: https://lore.kernel.org/oe-kbuild-all/[email protected]/
> Signed-off-by: Matthieu Baerts <[email protected]>
> [ added missing ifdefs for BTF_ID cgroup definitions ]
> Signed-off-by: Jiri Olsa <[email protected]>
Thank you, this (finally, reported first on Oct 20!) fixes the build of
e.g. m68k/defconfig.
Tested-by: Geert Uytterhoeven <[email protected]>
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]
In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds