Why need a lock in memory/capability map

Yuxin Ren ryx at gwmail.gwu.edu
Mon Jul 21 04:15:23 CEST 2014

This makes more sense.
But could you explain in a litter more detail?
What data structures are protected? Task struture or something else?

Thank you very much.

On Mon, Jul 21, 2014 at 5:34 AM, Adam Lackorzynski <
adam at os.inf.tu-dresden.de> wrote:

> On Fri Jul 18, 2014 at 18:34:31 -0400, Yuxin Ren wrote:
> > I note that when a thread does memory or capability mapping, both over
> > system call and IPC, it needs take a lock, which is the existence_lock of
> > target task. I cannot understand it needs take a per task, as cap/page
> > table are per thread.
> > What data does this lock to protect?
> Memory as well as caps are per task, so the lock makes sure that the
> task does not disappear while an operation is in progress.
> Adam
> --
> Adam                 adam at os.inf.tu-dresden.de
>   Lackorzynski         http://os.inf.tu-dresden.de/~adam/
> _______________________________________________
> l4-hackers mailing list
> l4-hackers at os.inf.tu-dresden.de
> http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://os.inf.tu-dresden.de/pipermail/l4-hackers/attachments/20140721/ed4e9132/attachment.html>

More information about the l4-hackers mailing list