On Fri, Jan 29, 2021 at 03:17:02PM +0000, Juraj Linkeš wrote: > > > > -----Original Message----- > > From: Bruce Richardson <bruce.richard...@intel.com> > > Sent: Friday, January 29, 2021 4:01 PM > > To: Juraj Linkeš <juraj.lin...@pantheon.tech> > > Cc: tho...@monjalon.net; ruifeng.w...@arm.com; jerinjac...@gmail.com; > > hemant.agra...@nxp.com; ferruh.yi...@intel.com; abo...@pensando.io; > > dev@dpdk.org > > Subject: Re: [RFC PATCH v1] build: kni gcc cross-compilation support > > > > On Fri, Jan 29, 2021 at 02:47:57PM +0000, Juraj Linkeš wrote: > > > > > > > > > > -----Original Message----- > > > > From: Bruce Richardson <bruce.richard...@intel.com> > > > > Sent: Friday, January 29, 2021 3:42 PM > > > > To: Juraj Linkeš <juraj.lin...@pantheon.tech> > > > > Cc: tho...@monjalon.net; ruifeng.w...@arm.com; > > > > jerinjac...@gmail.com; hemant.agra...@nxp.com; > > > > ferruh.yi...@intel.com; abo...@pensando.io; dev@dpdk.org > > > > Subject: Re: [RFC PATCH v1] build: kni gcc cross-compilation support > > > > > > <snip> > > > > > > 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. > > > > > > > > > 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? > > Assuming that we want to install cross modules, then yes, although it's > incomplete. There's also the scenario when a user would use different > kernel_dir than the default for native builds. I don't know why anyone would > do that, but it is a theoretical possibility :-)
In the cross-compile install case, is the prefix /usr/aarch64-linux-gnu/ coming from a DESTDIR environment variable? If it is, then we could just use the kernel_dir option for the build path, and always install to /lib/modules/<ver>/... allowing any cross-compiler relocation to take care of the rest.
