linux-next: build warning after merge of the bpf-next tree

linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (htmldocs)
produced this warning:

kernel/bpf/helpers.c:3465: warning: expecting prototype for bpf_strlen(). Prototype was for bpf_strnlen() instead
kernel/bpf/helpers.c:3557: warning: expecting prototype for strcspn(). Prototype was for bpf_strcspn() instead

Introduced by commit

  e91370550f1f ("bpf: Add kfuncs for read-only string operations")

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Viktor Malik]

On 6/27/25 09:47, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the bpf-next tree, today's linux-next build (htmldocs)
> produced this warning:
> 
> kernel/bpf/helpers.c:3465: warning: expecting prototype for bpf_strlen(). Prototype was for bpf_strnlen() instead
> kernel/bpf/helpers.c:3557: warning: expecting prototype for strcspn(). Prototype was for bpf_strcspn() instead
> 
> Introduced by commit
> 
>   e91370550f1f ("bpf: Add kfuncs for read-only string operations")

Oh, good catch, thanks for the report.

Just sent a fix to bpf-next [1].

Viktor

[1]
https://lore.kernel.org/bpf/20250627082001.237606-1-vmalik@redhat.com/T/#u

linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (htmldocs)
produced this warning:

Documentation/bpf/bpf_iterators.rst:55: WARNING: Bullet list ends without a blank line; unexpected unindent. [docutils]

Introduced by commit

  7220eabff8cb ("bpf, docs: document open-coded BPF iterators")

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Andrii Nakryiko]

On Mon, May 12, 2025 at 1:49 AM Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> Hi all,
>
> After merging the bpf-next tree, today's linux-next build (htmldocs)
> produced this warning:
>
> Documentation/bpf/bpf_iterators.rst:55: WARNING: Bullet list ends without a blank line; unexpected unindent. [docutils]
>
> Introduced by commit
>
>   7220eabff8cb ("bpf, docs: document open-coded BPF iterators")

Thanks for the heads up! This was fixed by Khaled in [0].

  [0] https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git/commit/?id=79af71c5fe44f3973c666bab3e9e5845812d3b8b

>
> --
> Cheers,
> Stephen Rothwell

linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (htmldocs)
produced this warning:

Documentation/bpf/standardization/instruction-set.rst:121: ERROR: Unexpected indentation.
Documentation/bpf/standardization/instruction-set.rst:122: WARNING: Block quote ends without a blank line; unexpected unindent.

Introduced by commit

  2d9a925d0fbf ("bpf, docs: Expand set of initial conformance groups")

-- 
Cheers,
Stephen Rothwell

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linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (arm
multi_v7_defconfig) produced this warning:

net/ipv4/af_inet.c: In function 'inet_getname':
net/ipv4/af_inet.c:791:13: warning: unused variable 'sin_addr_len' [-Wunused-variable]
  791 |         int sin_addr_len = sizeof(*sin);
      |             ^~~~~~~~~~~~

Introduced by commit

  fefba7d1ae19 ("bpf: Propagate modified uaddrlen from cgroup sockaddr programs")

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

On Fri, 13 Oct 2023 11:40:07 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> After merging the bpf-next tree, today's linux-next build (arm
> multi_v7_defconfig) produced this warning:
> 
> net/ipv4/af_inet.c: In function 'inet_getname':
> net/ipv4/af_inet.c:791:13: warning: unused variable 'sin_addr_len' [-Wunused-variable]
>   791 |         int sin_addr_len = sizeof(*sin);
>       |             ^~~~~~~~~~~~
> 
> Introduced by commit
> 
>   fefba7d1ae19 ("bpf: Propagate modified uaddrlen from cgroup sockaddr programs")

This became a build failure for the i386 defconfig build, so I applied
the following patch:

From: Stephen Rothwell <sfr@canb.auug.org.au>
Date: Fri, 13 Oct 2023 16:25:08 +1100
Subject: [PATCH] fix up for "bpf: Propagate modified uaddrlen from cgroup sockaddr programs"

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
---
 net/ipv4/af_inet.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 7e27ad37b939..0fcab6b6cb04 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -788,7 +788,9 @@ int inet_getname(struct socket *sock, struct sockaddr *uaddr,
 	struct sock *sk		= sock->sk;
 	struct inet_sock *inet	= inet_sk(sk);
 	DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
+#ifdef CONFIG_CGROUP_BPF
 	int sin_addr_len = sizeof(*sin);
+#endif
 
 	sin->sin_family = AF_INET;
 	lock_sock(sk);
-- 
2.40.1

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Martin KaFai Lau]

On 10/12/23 10:30 PM, Stephen Rothwell wrote:
> Hi all,
> 
> On Fri, 13 Oct 2023 11:40:07 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>
>> After merging the bpf-next tree, today's linux-next build (arm
>> multi_v7_defconfig) produced this warning:
>>
>> net/ipv4/af_inet.c: In function 'inet_getname':
>> net/ipv4/af_inet.c:791:13: warning: unused variable 'sin_addr_len' [-Wunused-variable]
>>    791 |         int sin_addr_len = sizeof(*sin);
>>        |             ^~~~~~~~~~~~
>>
>> Introduced by commit
>>
>>    fefba7d1ae19 ("bpf: Propagate modified uaddrlen from cgroup sockaddr programs")
> 
> This became a build failure for the i386 defconfig build, so I applied
> the following patch:
> 
> From: Stephen Rothwell <sfr@canb.auug.org.au>
> Date: Fri, 13 Oct 2023 16:25:08 +1100
> Subject: [PATCH] fix up for "bpf: Propagate modified uaddrlen from cgroup sockaddr programs"
> 
> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
> ---
>   net/ipv4/af_inet.c | 2 ++
>   1 file changed, 2 insertions(+)
> 
> diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
> index 7e27ad37b939..0fcab6b6cb04 100644
> --- a/net/ipv4/af_inet.c
> +++ b/net/ipv4/af_inet.c
> @@ -788,7 +788,9 @@ int inet_getname(struct socket *sock, struct sockaddr *uaddr,
>   	struct sock *sk		= sock->sk;
>   	struct inet_sock *inet	= inet_sk(sk);
>   	DECLARE_SOCKADDR(struct sockaddr_in *, sin, uaddr);
> +#ifdef CONFIG_CGROUP_BPF
>   	int sin_addr_len = sizeof(*sin);
> +#endif

Thanks for the report and taking care of it.

Daan, something that was missed in ipv4 getname. It should be done similar to 
inet6_getname() in af_inet6.c such that it "return sin_addr_len;" in this 
function to avoid the compiler warning here in ipv4.

linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (htmldocs)
produced this warning:

Documentation/bpf/graph_ds_impl.rst:62: ERROR: Error in "code-block" directive:
maximum 1 argument(s) allowed, 12 supplied.

.. code-block:: c
        struct node_data {
          long key;
          long data;
          struct bpf_rb_node node;
        };

        struct bpf_spin_lock glock;
        struct bpf_rb_root groot __contains(node_data, node);


Introduced by commit

  c31315c3aa09 ("bpf, documentation: Add graph documentation for non-owning refs")

-- 
Cheers,
Stephen Rothwell

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linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (htmldocs)
produced this warning:

include/linux/netdevice.h:2381: warning: Function parameter or member 'xdp_features' not described in 'net_device'

Introduced by commit

  d3d854fd6a1d ("netdev-genl: create a simple family for netdev stuff")

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Alexei Starovoitov]

On Sun, Feb 5, 2023 at 7:54 PM Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> Hi all,
>
> After merging the bpf-next tree, today's linux-next build (htmldocs)
> produced this warning:
>
> include/linux/netdevice.h:2381: warning: Function parameter or member 'xdp_features' not described in 'net_device'
>
> Introduced by commit
>
>   d3d854fd6a1d ("netdev-genl: create a simple family for netdev stuff")

Lorenzo,
please take a look.

linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

After merging the bpf-next tree, today's linux-next build (powerpc
ppc64_defconfig) produced this warning:

kernel/bpf/btf.c:6588:13: warning: 'purge_cand_cache' defined but not used [-Wunused-function]
 6588 | static void purge_cand_cache(struct btf *btf)
      |             ^~~~~~~~~~~~~~~~

Introduced by commit

  1e89106da253 ("bpf: Add bpf_core_add_cands() and wire it into bpf_core_apply_relo_insn().")

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Stephen Rothwell]

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Hi all,

On Mon, 6 Dec 2021 10:55:30 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> After merging the bpf-next tree, today's linux-next build (powerpc
> ppc64_defconfig) produced this warning:
> 
> kernel/bpf/btf.c:6588:13: warning: 'purge_cand_cache' defined but not used [-Wunused-function]
>  6588 | static void purge_cand_cache(struct btf *btf)
>       |             ^~~~~~~~~~~~~~~~
> 
> Introduced by commit
> 
>   1e89106da253 ("bpf: Add bpf_core_add_cands() and wire it into bpf_core_apply_relo_insn().")

And this is a build failure for my x86_64 allmodconfig build.  So I
have used the bpf-next tree from next-20211202 again.

-- 
Cheers,
Stephen Rothwell

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Re: linux-next: build warning after merge of the bpf-next tree

[Andrii Nakryiko]

On Sun, Dec 5, 2021 at 4:44 PM Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
> Hi all,
>
> On Mon, 6 Dec 2021 10:55:30 +1100 Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> >
> > After merging the bpf-next tree, today's linux-next build (powerpc
> > ppc64_defconfig) produced this warning:
> >
> > kernel/bpf/btf.c:6588:13: warning: 'purge_cand_cache' defined but not used [-Wunused-function]
> >  6588 | static void purge_cand_cache(struct btf *btf)
> >       |             ^~~~~~~~~~~~~~~~
> >
> > Introduced by commit
> >
> >   1e89106da253 ("bpf: Add bpf_core_add_cands() and wire it into bpf_core_apply_relo_insn().")
>
> And this is a build failure for my x86_64 allmodconfig build.  So I
> have used the bpf-next tree from next-20211202 again.

This should be fixed by [0] which I just applied to bpf-next, thanks
for letting us know! The reason you noticed this and we didn't is
because your version of pahole is probably older than what we use
typically and doesn't yet support kernel module BTFs.

  [0] https://patchwork.kernel.org/project/netdevbpf/patch/20211207014839.6976-1-alexei.starovoitov@gmail.com/


>
> --
> Cheers,
> Stephen Rothwell