Re: [dpdk-dev] [RFC PATCH v1] build: kni gcc cross-compilation support

On Fri, Jan 29, 2021 at 02:47:57PM +0000, Juraj Linkeš wrote:

quoted

-----Original Message-----
From: Bruce Richardson <redacted>
Sent: Friday, January 29, 2021 3:42 PM
To: Juraj Linkeš <redacted>
Cc: thomas@monjalon.net; Ruifeng.Wang@arm.com; jerinjacobk@gmail.com;
hemant.agrawal@nxp.com; ferruh.yigit@intel.com; aboyer@pensando.io;
dev@dpdk.org
Subject: Re: [RFC PATCH v1] build: kni gcc cross-compilation support

<snip>

quoted

quoted

quoted

Can we find some way of getting it working for both cases.
For native builds we want:

* build kernel-dir = /lib/modules/<ver>/build
* install dir = /lib/modules/<ver>/extra/dpdk

What are the expected equivalent paths for cross building?

The ubuntu1804 packages are installing aarch64 cross files to /usr/aarch64-

linux-gnu, so we could install it to /usr/aarch64-linux-
gnu/lib/modules/<ver>/extra/dpdk, or
/usr/<cross_triple>/lib/modules/<ver>/extra/dpdk in general. I think we can get
<ver> from 'make kernelversion', so that would work, although I'm not sure this
is the right place.

quoted

So what do you specify as the "kernel_dir" for the cross compile?

The place where I cloned (and cross-compiled) linux sources: $HOME/linux.

So I think the key problem is that for cross-compilation you need two
completely independent paths, while for native builds the two can be
linked. Is that correct?