Trouble with l4rm_region_cache slab

Adam Lackorzynski adam at
Tue Jan 22 22:09:03 CET 2008

On Tue Jan 22, 2008 at 12:37:45 +0100, Marc CHALAND wrote:
> After more investigation, I've found that slab_alloc and slab_free on
> l4rm_region_cache are not all into a critical section (for example:
> l4rm_attach may be called by several threads). At first, I though
> region_list_lock aimed at that, but in fact, this is not the case.
> My first idea is to put slab_alloc between l4rm_lock_region_list and
> l4rm_unlock_region_list into l4rm_region_desc_alloc. Same for
> slab_free. But I'm not sure this is a good idea. What is your opinion
> ?

You're right that the slab objects themselves were not locked. The fix
was not as easy as proposed but I think I have fixed this (update l4env
and l4rm packages). I hope this fixes your issue. Thanks for reporting,
very valuable!

Adam                 adam at

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