[dpdk-dev] [PATCH] kernel/linux: fix modules install path

[Igor Ryzhov]

Bruce,

>From my understanding, kernel_dir is a directory with kernel headers needed
for modules building. When it's formed automatically, yes, it will be
"/lib/modules/version/build" and we can get installation directory by
stripping
"/build". But when it's set manually, it can be set to, for example,
"/usr/src/linux-headers-version", and build will be successful, but we
won't be
able to strip "/build" as there is no "/build".

Which path should be used for installation in cross-compile case, when the
kernel_dir is set manually?



On Mon, Jun 10, 2019 at 12:37 PM Bruce Richardson <
bruce.richardson at intel.com> wrote:

> On Mon, Jun 10, 2019 at 11:25:52AM +0300, Igor Ryzhov wrote:
> > Currently kernel modules are installed into /usr/src/ instead of
> > /lib/modules when meson build system is used. This patch fixes that.
> >
> > Old build option "kernel_dir" is changed to "kernel_version".
> >
> > Signed-off-by: Igor Ryzhov <iryzhov at nfware.com>
> > ---
> >  kernel/linux/igb_uio/meson.build |  2 +-
> >  kernel/linux/kni/meson.build     |  2 +-
> >  kernel/linux/meson.build         | 16 +++++++++-------
> >  meson_options.txt                |  4 ++--
> >  4 files changed, 13 insertions(+), 11 deletions(-)
> >
> > diff --git a/kernel/linux/igb_uio/meson.build
> b/kernel/linux/igb_uio/meson.build
> > index f5a9d5ccf..5093610e3 100644
> > --- a/kernel/linux/igb_uio/meson.build
> > +++ b/kernel/linux/igb_uio/meson.build
> > @@ -16,5 +16,5 @@ custom_target('igb_uio',
> >               'modules'],
> >       depends: mkfile,
> >       install: true,
> > -     install_dir: kernel_dir + '/../extra/dpdk',
> > +     install_dir: kernel_install_dir + '/extra/dpdk',
> >       build_by_default: get_option('enable_kmods'))
> > diff --git a/kernel/linux/kni/meson.build b/kernel/linux/kni/meson.build
> > index a9f48b0e6..8a902d2ed 100644
> > --- a/kernel/linux/kni/meson.build
> > +++ b/kernel/linux/kni/meson.build
> > @@ -25,5 +25,5 @@ custom_target('rte_kni',
> >       depends: kni_mkfile,
> >       console: true,
> >       install: true,
> > -     install_dir: kernel_dir + '/../extra/dpdk',
> > +     install_dir: kernel_install_dir + '/extra/dpdk',
> >       build_by_default: get_option('enable_kmods'))
> > diff --git a/kernel/linux/meson.build b/kernel/linux/meson.build
> > index a37c95752..5a9303b33 100644
> > --- a/kernel/linux/meson.build
> > +++ b/kernel/linux/meson.build
> > @@ -3,19 +3,21 @@
> >
> >  subdirs = ['igb_uio', 'kni']
> >
> > -# if we are cross-compiling we need kernel_dir specified
> > -if get_option('kernel_dir') == '' and meson.is_cross_build()
> > -     warning('Need "kernel_dir" option for kmod compilation when
> cross-compiling')
> > +# if we are cross-compiling we need kernel_version specified
> > +if get_option('kernel_version') == '' and meson.is_cross_build()
> > +     warning('Need "kernel_version" option for kmod compilation when
> cross-compiling')
> >       subdir_done()
> >  endif
>
> Looking at the patch now, I'm not sure that this change from kernel_dir to
> kernel_version is the right thing to do - since it almost certainly cause
> issues for cross-compiling. The kernel modules almost certainly won't be in
> the host's /lib/modules folder in cross-compile cases, so I think we need
> to continue to specify a path to the kernel modules folder.
>
> To me the simplest option is that we should take the path to the kernels
> module folder i.e. same as now, just without the "/build". A comment update
> in the meson_options.txt file should be all that is needed to modify that
> parameter, and we should be able to have the meson.build file automatically
> strip "/build" off the path in order to enable backward compatibility. What
> do you think?
>
> /Bruce
>
>