Re: [PATCH v2 1/2] bpf: add __weak hook for allocating executable memory

From: Ard Biesheuvel
Date: Thu Nov 22 2018 - 16:08:07 EST




> On 22 Nov 2018, at 21:01, kbuild test robot <lkp@xxxxxxxxx> wrote:
>
> Hi Ard,
>
> I love your patch! Yet something to improve:
>

Ugh, apologies for this. Iâm sure i build tested /something/ but clearly not what i should have tested.

In any case, following up on the discussion Iâll have to respin this in any case. Iâll triple check next time that what i send out was tested properly.


> [auto build test ERROR on bpf-next/master]
> [also build test ERROR on v4.20-rc3 next-20181122]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
>
> url: https://github.com/0day-ci/linux/commits/Ard-Biesheuvel/bpf-permit-JIT-allocations-to-be-served-outside-the-module-region/20181123-033144
> base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
> config: x86_64-randconfig-x002-201846 (attached as .config)
> compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
> reproduce:
> # save the attached .config to linux build tree
> make ARCH=x86_64
>
> All error/warnings (new ones prefixed by >>):
>
> kernel//bpf/core.c: In function 'bpf_jit_free_exec':
>>> kernel//bpf/core.c:632:24: error: 'size' undeclared (first use in this function); did you mean 'ksize'?
> return module_memfree(size);
> ^~~~
> ksize
> kernel//bpf/core.c:632:24: note: each undeclared identifier is reported only once for each function it appears in
>>> kernel//bpf/core.c:632:9: warning: 'return' with a value, in function returning void
> return module_memfree(size);
> ^~~~~~~~~~~~~~
> kernel//bpf/core.c:630:13: note: declared here
> void __weak bpf_jit_free_exec(const void *addr)
> ^~~~~~~~~~~~~~~~~
>
> vim +632 kernel//bpf/core.c
>
> 629
> 630 void __weak bpf_jit_free_exec(const void *addr)
> 631 {
>> 632 return module_memfree(size);
> 633 }
> 634
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all Intel Corporation
> <.config.gz>