Re: Ask for help about bpf map

["luwei (O)" <luwei32@huawei.com>]

Hi Andrii and toke,

     I have sovled this issue. The reason is that my iproute2 does not 
support libbpf, once I compile iproute2 with libbpf, it works. Thanks 
for reply!

在 2021/7/14 10:02 AM, luwei (O) 写道:
> I tried 5.13 version in this page: 
> https://git.kernel.org/pub/scm/network/iproute2/iproute2.git , still 
> failed with the same error.
>
> 在 2021/7/14 9:05 AM, luwei (O) 写道:
>> I have updated the iproute2 according this page: 
>> https://github.com/cilium/cilium/issues/7446
>>
>> Now I use this version of iproute2: 
>> https://github.com/shemminger/iproute2
>>
>> The version of iproute2 is 5.11, and the kernel version is 5.13(the 
>> latest version).
>>
>>
>> 在 2021/7/14 1:07 AM, Toke Høiland-Jørgensen 写道:
>>> Andrii Nakryiko <andrii.nakryiko@gmail.com> writes:
>>>
>>>> On Mon, Jul 12, 2021 at 11:35 PM luwei (O) <luwei32@huawei.com> wrote:
>>>>> Hi, List:
>>>>>
>>>>>         I am a beginner about bpf and working on XDP now. I meet a
>>>>> problem and feel difficult to figure it out.
>>>>>
>>>>>         In my following codes, I use two ways to define my_map: in 
>>>>> SEC
>>>>> maps and SEC .maps respectively. When I load the xdp_kern.o file,
>>>>>
>>>>> It has different results. The way I load is: ip link set dev ens3 xdp
>>>>> obj xdp1_kern.o sec xdp1.
>>>>>
>>>>>         when I define my_map using SEC maps, it loads successfully 
>>>>> but
>>>>> fails to load using SEC .maps, it reports:
>>>>>
>>>>> "
>>>>>
>>>>> [12] TYPEDEF __u32 type_id=13
>>>>> [13] INT unsigned int size=4 bits_offset=0 nr_bits=32 encoding=(none)
>>>>> [14] FUNC_PROTO (anon) return=2 args=(10 ctx)
>>>>> [15] FUNC xdp_prog1 type_id=14
>>>>> [16] INT char size=1 bits_offset=0 nr_bits=8 encoding=SIGNED
>>>>> [17] ARRAY (anon) type_id=16 index_type_id=4 nr_elems=4
>>>>> [18] VAR _license type_id=17 linkage=1
>>>>> [19] DATASEC .maps size=0 vlen=1 size == 0
>>>>>
>>>>>
>>>>> Prog section 'xdp1' rejected: Permission denied (13)!
>>>>>    - Type:         6
>>>>>    - Instructions: 9 (0 over limit)
>>>>>    - License:      GPL
>>>>>
>>>>> Verifier analysis:
>>>>>
>>>>> 0: (b7) r1 = 0
>>>>> 1: (63) *(u32 *)(r10 -4) = r1
>>>>> last_idx 1 first_idx 0
>>>>> regs=2 stack=0 before 0: (b7) r1 = 0
>>>>> 2: (bf) r2 = r10
>>>>> 3: (07) r2 += -4
>>>>> 4: (18) r1 = 0x0
>>>> this shouldn't be 0x0.
>>>>
>>>> I suspect you have an old iproute2 which doesn't yet use libbpf to
>>>> load BPF programs, so .maps definition is not yet supported. cc'ing
>>>> netdev@vger, David and Toke
>>> That would be my guess as well; what's the output of 'ip -V'?
>>>
>>> -Toke
>>>
>>> .
>>
-- 
Best Regards,
Lu Wei