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

[Jeff Layton]

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.

-- 
Jeff Layton <jlayton@xxxxxxxxxx>