link failures with bpf_map_xxx_elem_proto calls from net/core/filiter.c

link failures with bpf_map_xxx_elem_proto calls from net/core/filiter.c

[Or Gerlitz]

Hi Daniel,

With net-next (and probably net or Linus tree too), I am getting these 
link failures

net/built-in.o:(.rodata+0x2210): undefined reference to 
`bpf_map_lookup_elem_proto'
net/built-in.o:(.rodata+0x2218): undefined reference to 
`bpf_map_update_elem_proto'
net/built-in.o:(.rodata+0x2220): undefined reference to 
`bpf_map_delete_elem_proto'

which are resolved when CONFIG_BPF_SYSCALL is added to the kernel 
config, I see now t hat this 4.0-rc1 commit d4052c4aea0cf "ebpf: remove 
CONFIG_BPF_SYSCALL ifdefs in socket filter code" removed the ifdefing, 
not sure what does "BPF internal header can deal with it" means.

Or.

Re: link failures with bpf_map_xxx_elem_proto calls from net/core/filiter.c

[Or Gerlitz]

On 3/4/2015 10:42 AM, Or Gerlitz wrote:
> Hi Daniel,
>
> With net-next (and probably net or Linus tree too), I am getting these 
> link failures
>
> net/built-in.o:(.rodata+0x2210): undefined reference to 
> `bpf_map_lookup_elem_proto'
> net/built-in.o:(.rodata+0x2218): undefined reference to 
> `bpf_map_update_elem_proto'
> net/built-in.o:(.rodata+0x2220): undefined reference to 
> `bpf_map_delete_elem_proto'
>

suddenly solved after make clean and make, probably a leftover from the 
fact that net-next was rebased tonight from 3.19 to 4.0-rc2

Or.

Re: link failures with bpf_map_xxx_elem_proto calls from net/core/filiter.c

[Alexei Starovoitov]

On 3/4/15 12:56 AM, Or Gerlitz wrote:
> On 3/4/2015 10:42 AM, Or Gerlitz wrote:
>> Hi Daniel,
>>
>> With net-next (and probably net or Linus tree too), I am getting these
>> link failures
>>
>> net/built-in.o:(.rodata+0x2210): undefined reference to
>> `bpf_map_lookup_elem_proto'
>> net/built-in.o:(.rodata+0x2218): undefined reference to
>> `bpf_map_update_elem_proto'
>> net/built-in.o:(.rodata+0x2220): undefined reference to
>> `bpf_map_delete_elem_proto'
>>
>
> suddenly solved after make clean and make, probably a leftover from the
> fact that net-next was rebased tonight from 3.19 to 4.0-rc2

that actually a real issue and Daniel has a patch that fixes it.
Will be submitted soon.

Re: link failures with bpf_map_xxx_elem_proto calls from net/core/filiter.c

[Daniel Borkmann]

On 03/04/2015 09:42 AM, Or Gerlitz wrote:
> Hi Daniel,
>
> With net-next (and probably net or Linus tree too), I am getting these link failures
>
> net/built-in.o:(.rodata+0x2210): undefined reference to `bpf_map_lookup_elem_proto'
> net/built-in.o:(.rodata+0x2218): undefined reference to `bpf_map_update_elem_proto'
> net/built-in.o:(.rodata+0x2220): undefined reference to `bpf_map_delete_elem_proto'
>
> which are resolved when CONFIG_BPF_SYSCALL is added to the kernel config, I see now t hat this 4.0-rc1 commit d4052c4aea0cf "ebpf: remove CONFIG_BPF_SYSCALL ifdefs in socket filter code" removed the ifdefing, not sure what does "BPF internal header can deal with it" means.

Sorry, I was travelling whole day yesterday.

Will send out a patch today.

Thanks,
Daniel

Re: link failures with bpf_map_xxx_elem_proto calls from net/core/filiter.c

[Daniel Borkmann]

On 03/04/2015 09:56 AM, Or Gerlitz wrote:
> On 3/4/2015 10:42 AM, Or Gerlitz wrote:
>> Hi Daniel,
>>
>> With net-next (and probably net or Linus tree too), I am getting these link failures
>>
>> net/built-in.o:(.rodata+0x2210): undefined reference to `bpf_map_lookup_elem_proto'
>> net/built-in.o:(.rodata+0x2218): undefined reference to `bpf_map_update_elem_proto'
>> net/built-in.o:(.rodata+0x2220): undefined reference to `bpf_map_delete_elem_proto'
>
> suddenly solved after make clean and make, probably a leftover from the fact that net-next was rebased tonight from 3.19 to 4.0-rc2

Okay, I see. I got a report from Fengguang, he told me that he sees a linker issue only
on avr32 and openrisc archs.

Cooking patch to resolve it ...