Hi,
Shouldn't IPC restrictions and such be implemented on top of L4, in some OS personality?
Thank you,
Jorge
On 8/7/07, Gernot Heiser gernot@nicta.com.au wrote:
On Tue, 7 Aug 2007 13:26:58 +0800, "Wei Shen" cquark@gmail.com
said: WS> Hi, WS> On 8/3/07, Gernot Heiser gernot@nicta.com.au wrote:
WS> The commercial OKL4 microkernel is converging on the seL4 API, it WS> presently contains simplified versions of IPC control and all kernel WS> resource allocation is under control of a user-level policy server. It WS> should implement a full seL4 API probably sometime next year.
WS> Gernot
WS> I have several questions: WS> 1)What does "simplified versions of IPC control" refer to?
There is a privileged IpcControl() syscall that allows you to set IPC restrictions on an address space (send anywhere, send anywhere except some, send only to some).
WS> 2)"all kernel resource allocation is under control of a user-level policy WS> server" - does the user-level policy server refer to Iguana?
As far as the kernel is concerned, it's the root task. In the OKL4 system the root task is Iguana.
WS> 3)Can these features you noted be found in current Pistachio-e and Iguana WS> release? All they belong to close-source part of OKL4?
They are in the released open-source OKL4l, and nicely documented in the very extensive (260 page) OKL4 Microkernel Programming Manual available at http://portal.ok-labs.com/
There is no closed-source part of OKL4, other than platform code that is specific to proprietary customer hardware. However, there is a release backlog (sorry). Nevertheless, what you are asking for is released, supported, deployed by commercial customers, and open source.
Gernot
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