Re: [PATCH] net: bridge: Fix jump_label config

[Kefeng Wang <wangkefeng.wang@huawei.com>]

On 2021/2/27 4:19, Cong Wang wrote:
> On Thu, Feb 25, 2021 at 5:39 PM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>>
>> On 2021/2/26 5:22, Cong Wang wrote:
>>> On Wed, Feb 24, 2021 at 8:03 AM Kefeng Wang <wangkefeng.wang@huawei.com> wrote:
>>>> HAVE_JUMP_LABLE is removed by commit e9666d10a567 ("jump_label: move
>>>> 'asm goto' support test to Kconfig"), use CONFIG_JUMP_LABLE instead
>>>> of HAVE_JUMP_LABLE.
>>>>
>>>> Fixes: 971502d77faa ("bridge: netfilter: unroll NF_HOOK helper in bridge input path")
>>>> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
>>> Hmm, why do we have to use a macro here? static_key_false() is defined
>>> in both cases, CONFIG_JUMP_LABEL=y or CONFIG_JUMP_LABEL=n.
>> It seems that all nf_hooks_needed related are using the macro,
>>
>> see net/netfilter/core.c and include/linux/netfilter.h,
>>
>>     #ifdef CONFIG_JUMP_LABEL
>>     struct static_key nf_hooks_needed[NFPROTO_NUMPROTO][NF_MAX_HOOKS];
>> EXPORT_SYMBOL(nf_hooks_needed);
>> #endif
>>
>>     nf_static_key_inc()/nf_static_key_dec()
> Same question: why? Clearly struct static_key is defined in both cases:

Hi Cong,  the nf_hooks_needed is wrapped up by this macro, so this place 
should use it,

or we will meet the build issue,  thanks.

../net/bridge/br_input.c: In function ‘nf_hook_bridge_pre’:
../net/bridge/br_input.c:211:25: error: ‘nf_hooks_needed’ undeclared 
(first use in this function)
   211 |  if 
(!static_key_false(&nf_hooks_needed[NFPROTO_BRIDGE][NF_BR_PRE_ROUTING]))


>
> #else
> struct static_key {
>          atomic_t enabled;
> };
> #endif  /* CONFIG_JUMP_LABEL */
>
> Thanks.
>