[Devel] Re: [PATCH] Memory shortage can result in inconsistent flocks state

[Balbir Singh]

On 9/13/07, Pavel Emelyanov <xemul at openvz.org> wrote:
> J. Bruce Fields wrote:
> > On Tue, Sep 11, 2007 at 04:38:13PM +0400, Pavel Emelyanov wrote:
> >> This is a known feature that such "re-locking" is not atomic,
> >> but in the racy case the file should stay locked (although by
> >> some other process), but in this case the file will be unlocked.
> >
> > That's a little subtle (I assume you've never seen this actually
> > happen?), but it makes sense to me.
>
> Well, this situation is hard to notice since usually programs
> try to finish up when some error is returned from the kernel,
> but I do believe that this could happen in one of the openvz
> kernels since we limit the kernel memory usage for "containers"
> and thus -ENOMEM is a common error.
>

The fault injection framework should be able to introduce the same
error. Of course hitting the error would require careful setup of the
fault parameters.

Balbir