[Linux-cluster] DLM user API for lock value block

[Jean-Marc Saffroy]

On Tue, 6 Dec 2016, David Teigland wrote:

> I haven't looked at your test to check if you're actually seeing this bug,
> but you'll want this fix in any case:
> 
> http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/fs/dlm/user.c?id=b96f465035f9fae83c1d8de3e80eecfe6877608c

That's definitely the issue I have.

> In the following lvmlockd code, you can see an example of working around
> that bug if you don't have immediate access to a newer kernel:
> 
> https://git.fedorahosted.org/cgit/lvm2.git/tree/daemons/lvmlockd/lvmlockd-dlm.c

Indeed, I have to work with not-so-recent distributions and their kernels, 
so a workaround is much needed.

Adding a similar workaround in my test does help! But only with a single 
process, because with more I quickly get a conversion deadlock error. :( I 
will need to think more about this.

Thanks a lot for the pointers!


Cheers,
JM

-- 
saffroy at gmail.com