Re: [Virtio-fs] [PATCH] virtiofsd: Disable remote posix locks by default

[Vivek Goyal]

On Thu, Aug 06, 2020 at 08:20:39AM +0000, misono.tomohiro@fujitsu.com wrote:
> > Right now we enable remote posix locks by default. That means when guest 
> > does a posix lock it sends request to server
> > (virtiofsd). But currently we only support non-blocking posix lock and 
> > return -EOPNOTSUPP for blocking version.
> > 
> > This means that existing applications which are doing blocking posix locks 
> > get -EOPNOTSUPP and fail. To avoid this,
> > people have been running virtiosd with option "-o no_posix_lock". For new 
> > users it is still a surprise and trial and error
> > takes them to this option.
> > 
> > Given posix lock implementation is not complete in virtiofsd, disable it by 
> > default. This means that posix locks will work
> > with-in applications in a guest but not across guests. Anyway we don't 
> > support sharing filesystem among different guests
> > yet in virtiofs so this should not lead to any kind of surprise or 
> > regression and will make life little easier for virtiofs users.
> > 
> > Reported-by: Aa Aa <jimbothom@yandex.com>
> > Suggested-by: Miklos Szeredi <mszeredi@redhat.com>
> > Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
> > ---
> >  tools/virtiofsd/passthrough_ll.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> We should update docs/tools/virtiofsd.rst as well. Given that:
>  Reviewed-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>

Good point Misono. I will update doc to reflect that now default
is "no_posix_lock". Will send V2 and retain all the Reviewed-by tags.

Thanks
Vivek