Re: [dpdk-dev] [PATCH v3] usertools/devbind: fix binding for built-in kernel drivers

["Liu, Yongxin" <Yongxin.Liu@windriver.com>]

> -----Original Message-----
> From: Burakov, Anatoly <anatoly.burakov@intel.com>
> Sent: Thursday, November 19, 2020 20:19
> To: Liu, Yongxin <Yongxin.Liu@windriver.com>; dev@dpdk.org;
> thomas@monjalon.net
> Subject: Re: [dpdk-dev] [PATCH v3] usertools/devbind: fix binding for
> built-in kernel drivers
> 
> 
> On 19-Nov-20 7:16 AM, Yongxin Liu wrote:
> > A driver can be loaded as a dynamic module or a built-in module.
> > In commit 681a67288655 ("usertools: check if module is loaded before
> > binding"), script only checks modules in /sys/module/.
> >
> > However, for built-in kernel driver, it only shows up in /sys/module/,
> > if it has a version or at least one parameter. So add check for
> > modules in /lib/modules/$(uname -r)/modules.builtin.
> >
> > Thanks for Anatoly Burakov's advice.
> >
> > Signed-off-by: Yongxin Liu <yongxin.liu@windriver.com>
> > ---
> >
> > v3:
> >   - Add built-in module list in loaded_modules for checking
> >     instead of removing error check.
> >
> > v2:
> >   - fix git commit description style in commit log
> >   - fix typo spelling
> >
> > ---
> >   usertools/dpdk-devbind.py | 8 +++++++-
> >   1 file changed, 7 insertions(+), 1 deletion(-)
> >
> > diff --git a/usertools/dpdk-devbind.py b/usertools/dpdk-devbind.py
> > index 99112b7ab..5b34ccd2a 100755
> > --- a/usertools/dpdk-devbind.py
> > +++ b/usertools/dpdk-devbind.py
> > @@ -181,7 +181,13 @@ def module_is_loaded(module):
> >
> >       loaded_modules = sysfs_mods
> >
> > -    return module in sysfs_mods
> > +    # add built-in modules as loaded
> > +    builtin_mods = subprocess.check_output(["cat /lib/modules/$(uname
> > + -r)/modules.builtin"], shell=True).splitlines()
> 
> I'd rather not call shell directly, it's bad practice and is potentially
> unsafe. The $(uname -r) can be replaced with:
> 
>         import platform
>         release = platform.uname().release  # equivalent to $(uname -r)
> 
> The rest can follow:
> 
>         filename = os.path.join("/lib/modules/", release,
> "modules.builtin")
>         # read the file contents, split lines, etc.
> 
> Also, please check if file exists to ensure we don't crash the script.
> 
> > +    for mod in builtin_mods:
> > +        mod_name = os.path.basename(mod.decode("utf8")).split(".ko",
> > + 1)
> 
> os.path.splitext(os.path.basename(...))?

Thanks Anatoly for your detailed instruction.
v4 has been sent.

/Yongxin


> 
> > +        loaded_modules.append(mod_name[0])
> > +
> > +    return module in loaded_modules
> >
> >
> >   def check_modules():
> >
> 
> 
> --
> Thanks,
> Anatoly