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Date:   Sun, 2 May 2021 13:16:12 +0200
From:   Petr Vorel <petr.vorel@gmail.com>
To:     Heiko Thiery <heiko.thiery@gmail.com>
Cc:     netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
        Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [PATCH iproute2-next v2] lib/fs: fix issue when
 {name,open}_to_handle_at() is not implemented
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Reply-To: Petr Vorel <petr.vorel@gmail.com>
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> Hi Petr,

> Am Fr., 30. Apr. 2021 um 21:29 Uhr schrieb Petr Vorel <petr.vorel@gmail.com>:

> > Hi,

> > > > +++ b/lib/fs.c
> > > > @@ -30,6 +30,27 @@
> > > >  /* if not already mounted cgroup2 is mounted here for iproute2's use */
> > > >  #define MNT_CGRP2_PATH  "/var/run/cgroup2"

> > > > +
> > > > +#ifndef defined HAVE_HANDLE_AT
> > > This is also wrong, it must be:
> > > #ifndef HAVE_HANDLE_AT

> > > > +struct file_handle {
> > > > +   unsigned handle_bytes;
> > > > +   int handle_type;
> > > > +   unsigned char f_handle[];
> > > > +};
> > > > +
> > > > +int name_to_handle_at(int dirfd, const char *pathname,
> > > > +   struct file_handle *handle, int *mount_id, int flags)
> > > > +{
> > > > +   return syscall(name_to_handle_at, 5, dirfd, pathname, handle,
> > > > +                  mount_id, flags);
> > > Also I overlooked bogus 5 parameter, why is here? Correct is:

> > >       return syscall(__NR_name_to_handle_at, dfd, pathname, handle,
> > >                          mount_id, flags);
> > Uh, one more typo on my side, sorry (dfd => dirfd):
> >         return syscall(__NR_name_to_handle_at, dirfd, pathname, handle,
> >                            mount_id, flags);


> Thanks for the review and finding the sloppiness. I really should test
> the changes before. Nevertheless, I will prepare a new version and
> test it this time.
I tested ss with changed I proposed and it looks like it's ok.
But I run ss on qemu without any daemon running => I'll retest your v3 once you
post it with some daemons running so that the code is really triggered.

Kind regards,
Petr

> BR,