Comment # 2 on bug 1145007 from Chris F

(In reply to Jan Kara from comment #1)
> This is a result of commit 9e8925b67a80:
> 
>     locks: Allow disabling mandatory locking at compile time
>     
>     Mandatory locking appears to be almost unused and buggy and there
>     appears no real interest in doing anything with it.  Since effectively
>     no one uses the code and since the code is buggy let's allow it to be
>     disabled at compile time.  I would just suggest removing the code but
>     undoubtedly that will break some piece of userspace code somewhere.
>     
>     For the distributions that don't care about this piece of code
>     this gives a nice starting point to make mandatory locking go away.
> 
> So I suppose not supporting mandatory locking anymore was a deliberate
> decision. This is actually nothing ext4 specific - rather a generic VFS
> change.
> 
> Do you really use mandatory locking or was that just a leftover from the
> past?

Hi,

we used the havp -http Anti Virus Proxy for years. Unfortunately one of the
requirements is "You HAVE TO use mandatory locks on your scanning filesystem!"
-> http://www.havp.org/downloads/

After upgrading Leap 42.3 -> 15.1 the root fs boots in readonly. Not cool.
There is no warning about 'buggy' in the man page 'mount(8).

Anyhow, we don't use havp anymore. We switched to squidclamav as http virus
proxy, so we don't need mandatoy locking anymore.