[ovs-dev] [PATCH] docs: Add header install command for afxdp.

William Tu u9012063 at gmail.com
Thu Jan 23 16:58:12 UTC 2020


On Thu, Jan 23, 2020 at 02:14:03PM +0100, Ilya Maximets wrote:
> > The 'XDP_RING_NEED_WAKEUP' and related flags are defined if_xdp.h, so after
> > installing newer kernel, users have to update the kernel's header files,
> > by doing:
> >   $ make headers_install INSTALL_HDR_PATH=/usr
> 
> > Otherwise the following error shows:
> > /usr/local/include/bpf/xsk.h: In function 'xsk_ring_prod__needs_wakeup':
> > /usr/local/include/bpf/xsk.h:82:21: error: 'XDP_RING_NEED_WAKEUP' undeclared \
> >   (first use in this function)
> >   return *r->flags & XDP_RING_NEED_WAKEUP;
> 
> > Reported-by: Tomek Osinski <osinstom at gmail.com>
> > Reported-at: https://osinstom.github.io/en/tutorial/ovs-afxdp-installation/
> > Signed-off-by: William Tu <u9012063 at gmail.com>
> > ---
> >  Documentation/intro/install/afxdp.rst | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/Documentation/intro/install/afxdp.rst b/Documentation/intro/install/afxdp.rst
> > index c4685fa7ebac..2683d8301bb7 100644
> > --- a/Documentation/intro/install/afxdp.rst
> > +++ b/Documentation/intro/install/afxdp.rst
> > @@ -125,6 +125,7 @@ Second, go into the Linux source directory and build libbpf in the tools
> >  directory::
> >  
> >    cd bpf-next/
> > +  make headers_install INSTALL_HDR_PATH=/usr
> >    cd tools/lib/bpf/
> >    make && make install
> >    make install_headers
> 
> I'm not sure about this change.  Especially in this section.
> This will work only if the running kernel is bpf-next kernel and if it's not
> this will cause unexpected runtime issues that will be really hard to debug and
> understand.  User should have its own kernel headers installed, not the headers
> from bpf-next.
> 
> If you really want this information in the docs, I'd suggest to put another
> item to previous "Build requirements" section that will say something like this:
> 
> """
> - If you're building your own kernel, be sure that you're installing kernel
>   headers too.  For example, with the following command::
> 
>     make headers_install INSTALL_HDR_PATH=/usr
> 
> - If you're using kernel from the distribution, be sure that corresponding
>   kernel headers package installed.
> """
> 
> Best regards, Ilya Maximets.

Hi Ilya,

That makes sense. I will send v2

William


More information about the dev mailing list