Re: [PATCH 5.13 126/127] fs: warn about impending deprecation of mandatory locks

[Naresh Kamboju]

On Thu, 2 Sept 2021 at 18:57, Jeff Layton <jlayton@xxxxxxxxxx> wrote:
>
> On Thu, 2021-09-02 at 18:50 +0530, Naresh Kamboju wrote:
> > On Tue, 24 Aug 2021 at 22:35, Sasha Levin <sashal@xxxxxxxxxx> wrote:
> > >
> > > From: Jeff Layton <jlayton@xxxxxxxxxx>
> > >
> > > [ Upstream commit fdd92b64d15bc4aec973caa25899afd782402e68 ]
> > >
> > > We've had CONFIG_MANDATORY_FILE_LOCKING since 2015 and a lot of distros
> > > have disabled it. Warn the stragglers that still use "-o mand" that
> > > we'll be dropping support for that mount option.
> > >
> > > Cc: stable@xxxxxxxxxxxxxxx
> > > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx>
> > > Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> > > ---
> > >  fs/namespace.c | 6 +++++-
> > >  1 file changed, 5 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/fs/namespace.c b/fs/namespace.c
> > > index caad091fb204..03770bae9dd5 100644
> > > --- a/fs/namespace.c
> > > +++ b/fs/namespace.c
> > > @@ -1716,8 +1716,12 @@ static inline bool may_mount(void)
> > >  }
> > >
> > >  #ifdef CONFIG_MANDATORY_FILE_LOCKING
> > > -static inline bool may_mandlock(void)
> > > +static bool may_mandlock(void)
> > >  {
> > > +       pr_warn_once("======================================================\n"
> > > +                    "WARNING: the mand mount option is being deprecated and\n"
> > > +                    "         will be removed in v5.15!\n"
> > > +                    "======================================================\n");
> >
> > We are getting this error on all devices while running LTP syscalls
> > ftruncate test cases
> > on all the stable-rc branches.
> >
>
> You really don't want to run those tests anymore then. The "mand" mount
> option no longer works, so any tests that require mandatory locking
> won't function correctly.

I will communicate this warning with the LTP community.
Thank you.

- Naresh