2018-05-29 04:05:17

by Yue Haibing

[permalink] [raw]
Subject: [PATCH bpf-next] bpf: hide the unused 'off' variable

The local variable is only used while CONFIG_IPV6 enabled

net/core/filter.c: In function ‘sk_msg_convert_ctx_access’:
net/core/filter.c:6489:6: warning: unused variable ‘off’ [-Wunused-variable]
int off;
^
This puts it into #ifdef.

Fixes: 303def35f64e ("bpf: allow sk_msg programs to read sock fields")
Signed-off-by: YueHaibing <[email protected]>
---
net/core/filter.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/core/filter.c b/net/core/filter.c
index 24e6ce8..0ce93ed 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -6486,7 +6486,9 @@ static u32 sk_msg_convert_ctx_access(enum bpf_access_type type,
struct bpf_prog *prog, u32 *target_size)
{
struct bpf_insn *insn = insn_buf;
+#if IS_ENABLED(CONFIG_IPV6)
int off;
+#endif

switch (si->off) {
case offsetof(struct sk_msg_md, data):
--
2.7.0




2018-05-29 10:36:03

by Arnd Bergmann

[permalink] [raw]
Subject: Re: [PATCH bpf-next] bpf: hide the unused 'off' variable

On Tue, May 29, 2018 at 4:40 AM, YueHaibing <[email protected]> wrote:
> The local variable is only used while CONFIG_IPV6 enabled
>
> net/core/filter.c: In function ‘sk_msg_convert_ctx_access’:
> net/core/filter.c:6489:6: warning: unused variable ‘off’ [-Wunused-variable]
> int off;
> ^
> This puts it into #ifdef.
>
> Fixes: 303def35f64e ("bpf: allow sk_msg programs to read sock fields")
> Signed-off-by: YueHaibing <[email protected]>

I was about to send the same patch and found you had already sent one.

Acked-by: Arnd Bergmann <[email protected]>

2018-05-29 15:55:01

by John Fastabend

[permalink] [raw]
Subject: Re: [PATCH bpf-next] bpf: hide the unused 'off' variable

On 05/29/2018 03:35 AM, Arnd Bergmann wrote:
> On Tue, May 29, 2018 at 4:40 AM, YueHaibing <[email protected]> wrote:
>> The local variable is only used while CONFIG_IPV6 enabled
>>
>> net/core/filter.c: In function ‘sk_msg_convert_ctx_access’:
>> net/core/filter.c:6489:6: warning: unused variable ‘off’ [-Wunused-variable]
>> int off;
>> ^
>> This puts it into #ifdef.
>>
>> Fixes: 303def35f64e ("bpf: allow sk_msg programs to read sock fields")
>> Signed-off-by: YueHaibing <[email protected]>
>
> I was about to send the same patch and found you had already sent one.
>
> Acked-by: Arnd Bergmann <[email protected]>
>

Thanks! I'm curious why kbuild bot didn't catch this. Will
try to dig into that in a bit.

Acked-by: John Fastabend <[email protected]>

2018-05-29 18:20:48

by Song Liu

[permalink] [raw]
Subject: Re: [PATCH bpf-next] bpf: hide the unused 'off' variable

On Tue, May 29, 2018 at 8:53 AM, John Fastabend
<[email protected]> wrote:
> On 05/29/2018 03:35 AM, Arnd Bergmann wrote:
>> On Tue, May 29, 2018 at 4:40 AM, YueHaibing <[email protected]> wrote:
>>> The local variable is only used while CONFIG_IPV6 enabled
>>>
>>> net/core/filter.c: In function ‘sk_msg_convert_ctx_access’:
>>> net/core/filter.c:6489:6: warning: unused variable ‘off’ [-Wunused-variable]
>>> int off;
>>> ^
>>> This puts it into #ifdef.
>>>
>>> Fixes: 303def35f64e ("bpf: allow sk_msg programs to read sock fields")
>>> Signed-off-by: YueHaibing <[email protected]>
>>
>> I was about to send the same patch and found you had already sent one.
>>
>> Acked-by: Arnd Bergmann <[email protected]>
>>
>
> Thanks! I'm curious why kbuild bot didn't catch this. Will
> try to dig into that in a bit.
>
> Acked-by: John Fastabend <[email protected]>

Acked-by: Song Liu <[email protected]>

2018-05-29 19:51:44

by Daniel Borkmann

[permalink] [raw]
Subject: Re: [PATCH bpf-next] bpf: hide the unused 'off' variable

On 05/29/2018 08:18 PM, Song Liu wrote:
> On Tue, May 29, 2018 at 8:53 AM, John Fastabend
> <[email protected]> wrote:
>> On 05/29/2018 03:35 AM, Arnd Bergmann wrote:
>>> On Tue, May 29, 2018 at 4:40 AM, YueHaibing <[email protected]> wrote:
>>>> The local variable is only used while CONFIG_IPV6 enabled
>>>>
>>>> net/core/filter.c: In function ‘sk_msg_convert_ctx_access’:
>>>> net/core/filter.c:6489:6: warning: unused variable ‘off’ [-Wunused-variable]
>>>> int off;
>>>> ^
>>>> This puts it into #ifdef.
>>>>
>>>> Fixes: 303def35f64e ("bpf: allow sk_msg programs to read sock fields")
>>>> Signed-off-by: YueHaibing <[email protected]>
>>>
>>> I was about to send the same patch and found you had already sent one.
>>>
>>> Acked-by: Arnd Bergmann <[email protected]>
>>
>> Thanks! I'm curious why kbuild bot didn't catch this. Will
>> try to dig into that in a bit.
>>
>> Acked-by: John Fastabend <[email protected]>
>
> Acked-by: Song Liu <[email protected]>

Applied to bpf-next, thanks Yue!