Hi all,

Greetings from me!

I install the newest Linux kernel 4.8.1 on CentOS 7, and want to try BPF feature. When I execute bcc/examples/hello_world.py,

the following error is generated:  

# ./hello_world.py

chdir(/lib/modules/4.8.1/build): No such file or directory

Traceback (most recent call last):

  File "./hello_world.py", line 11, in <module>

    BPF(text='int kprobe__sys_clone(void *ctx) { bpf_trace_printk("Hello, World!\\n"); return 0; }').trace_print()

  File "/usr/lib/python2.7/site-packages/bcc/__init__.py", line 205, in __init__

    raise Exception("Failed to compile BPF module %s" % src_file)

Exception: Failed to compile BPF module

I check the /lib/modules/4.8.1/ directory:  

lrwxrwxrwx.  1 root root     17 Oct 14 11:29 build -> /root/linux-4.8.1

lrwxrwxrwx.  1 root root     17 Oct 14 11:29 source -> /root/linux-4.8.1

The  /root/linux-4.8.1 is the folder which is used to build 4.8.1 kernel, since it occupies too much space, I delete it after installing. 

So to compile BPF module, does it mean I need to recover the linux-4.8.1 source code and build it again?