Re: [libvirt] Deadlock when using custom handlers
Hi Daniel,
On Sat, Aug 13, 2011 at 08:57:45PM -0700, Daniel P. Berrange wrote:
On Fri, Aug 12, 2011 at 11:54:28PM +0200, Guido Günther wrote:
[..snip..]
In the default libvirt event loop, the 'ff' callback is
always invoked
from a "clean" stack in the event loop, so you never have this problem
with re-entrancy.
> Working around this by removing the locks from
> virNetSocketRemoveIOCallback leads to another deadlock:
Yeah this is not a viable approach.
Sure. This was only to see what else fails.
>
> I didn't see a simple way to fix this but would welcome any suggestions.
IMHO we just have to document that event loop implementations
should make sure that the 'ff' callbacks are always invoked
from a clean stack. In the case of virt-viewer, this means
changing it to register a g_idle callback function to invoke
the 'ff' callback.
Patch for virt-viewer attached. I'll come up with a doc patch for
libvirt once I have a bit more time.
Cheers
-- Guido
Attachments:
- 0001-ff-callbacks-must-be-invoked-from-a-clean-stack.patch (text/x-diff — 2.2 KB)