xdp-loader - Couldn't attach XDP program about xdp-tools

[tohojo]

csh <[email protected]> writes:

> prog0() func#1... btf_vmlinux is malformed > Hmm, this looks like the kernel was compiled without BTF information? Kernel config ``` grep 'BTF' /boot/config-5.10.2-1.el8.elrepo.x86_64 # CONFIG_DEBUG_INFO_BTF is not set ```

Hmm, yeah, that's what I thought. Still not sure why that is needed, but I'm technically on holiday now, so will hold off on going digging until the new year :)

> Arg#0 type PTR in prog0() is not supported yet. > Not sure what that would lead to this error, though... I must have missed something when i first compiled from source, doing a clean re-compile of xdp-loader here is what i get, ``` xdp-loader]# ls Makefile README.org tests xdp-dispatcher.o xdp-loader xdp-loader.c xdp-loader]# ./xdp-loader load -vv --mode skb lo ../../xdp-tutorial/basic01-xdp-pass/xdp_pass_kern.o [.. snip ..] libxdp: DATASEC '.xdp_run_config' not found. libxdp: Verified XDP dispatcher version 1 <= 1 libxdp: Loading multiprog dispatcher for 1 programs libbpf: map 'xdp_disp.rodata': created successfully, fd=5 libbpf: added 60 insn from .text to prog xdp/dispatcher libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating prog0() func#1... btf_vmlinux is malformed Arg#0 type PTR in prog0() is not supported yet. processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0 libbpf: -- END LOG -- libbpf: failed to load program 'xdp/dispatcher' libbpf: failed to load object './xdp-dispatcher.o' libxdp: Got verifier error while loading dispatcher. libxdp: Falling back to loading single prog without dispatcher libxdp: Loaded XDP program xdp_prog_simple, got fd 5 libxdp: Replacing XDP fd -1 with 5 on ifindex 1 ``` Despite the above errors it's loading the example programs

Yeah, I implemented the fallback quite recently; but glad to see it working. This means you will only be able to load a single program on the interface, but other than that it should just work :)

[tohojo]

csh <[email protected]> writes:

Hello, I seem to be having a problem loading xdp programs using xdp-loader. When attempting to load the basic01-xdp-pass XDP program from the [xdp-tutorial](https://github.com/xdp-project/xdp-tutorial) examples, I get the following error's ``` xdp-loader load -v --mode skb lo basic01-xdp-pass/xdp_pass_kern.o Current rlimit is infinity or 0. Not raising Loading 1 files on interface 'lo'. XDP program 0: Run prio: 50. Chain call actions: XDP_PASS libxdp: Couldn't open BPF file Couldn't attach XDP program on iface 'lo': Kernel verifier blocks program loading(-4007) ``` Notable errors from `-vv` ``` libbpf: added 60 insn from .text to prog xdp/dispatcher libbpf: load bpf program failed: Invalid argument libbpf: -- BEGIN DUMP LOG --- libbpf: Validating prog0() func#1... btf_vmlinux is malformed

Hmm, this looks like the kernel was compiled without BTF information?

Arg#0 type PTR in prog0() is not supported yet.

Not sure what that would lead to this error, though...

[c-sh0]

prog0() func#1... btf_vmlinux is malformed
Hmm, this looks like the kernel was compiled without BTF information?

Kernel config

grep 'BTF' /boot/config-5.10.2-1.el8.elrepo.x86_64
# CONFIG_DEBUG_INFO_BTF is not set

Arg#0 type PTR in prog0() is not supported yet.
Not sure what that would lead to this error, though...

I must have missed something when i first compiled from source, doing a clean re-compile of xdp-loader here is what i get,

xdp-loader]# ls
Makefile  README.org  tests  xdp-dispatcher.o  xdp-loader  xdp-loader.c

xdp-loader]# ./xdp-loader load -vv --mode skb lo ../../xdp-tutorial/basic01-xdp-pass/xdp_pass_kern.o
[.. snip ..]

libxdp: DATASEC '.xdp_run_config' not found.
libxdp: Verified XDP dispatcher version 1 <= 1
libxdp: Loading multiprog dispatcher for 1 programs
libbpf: map 'xdp_disp.rodata': created successfully, fd=5
libbpf: added 60 insn from .text to prog xdp/dispatcher
libbpf: load bpf program failed: Invalid argument
libbpf: -- BEGIN DUMP LOG ---
libbpf:
Validating prog0() func#1...
btf_vmlinux is malformed
Arg#0 type PTR in prog0() is not supported yet.
processed 0 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0

libbpf: -- END LOG --
libbpf: failed to load program 'xdp/dispatcher'
libbpf: failed to load object './xdp-dispatcher.o'
libxdp: Got verifier error while loading dispatcher.
libxdp: Falling back to loading single prog without dispatcher
libxdp: Loaded XDP program xdp_prog_simple, got fd 5
libxdp: Replacing XDP fd -1 with 5 on ifindex 1

Despite the above errors it's loading the example programs

xdp-loader]# ./xdp-loader status
CURRENT XDP PROGRAM STATUS:

Interface        Prio  Program name     Mode     ID   Tag               Chain actions
-------------------------------------------------------------------------------------
lo                     xdp_prog_simple  skb      169  3b185187f1855c4c

I'm guessing the commit for xdp_program__attach_single() just hasn't made into the upstream package yet?

[tohojo]

Closing this issue - please reopen if you're still experiencing problems.