DragonFly kernel List (threaded) for 2007-02
DragonFly BSD
DragonFly kernel List (threaded) for 2007-02
[Date Prev][Date Next]  [Thread Prev][Thread Next]  [Date Index][Thread Index]

Re: Page fault handling in vpagetable area clarification

From: Aggelos Economopoulos <aoiko@xxxxxxxxxxxxxx>
Date: Thu, 8 Feb 2007 22:07:22 +0200

On Thursday 08 February 2007 19:12, Matthew Dillon wrote:
> :"when a virtual process running under a virtual kernel takes a page fault,
> : it must chain through the virtual kernel and cannot short-cut directly to
> : the real kernel to handle the page fault"
>     The real kernel does walk the virtual page table and can handle the
>     page fault for those pages that exist in the virtual page table.
>     However, just like the real kernel, the virtual kernel populates the
>     virtual page table 'on demand', which means that often there will not
>     be a page in the virtual page table for the real kernel to find.  When
>     that occurs the real kernel simulates a page fault for the virtual
>     kernel to handle.

Yes, I get that, it was the "/must/ chain through the virtual kernel" that 
gave me pause. Thanks for the clarification.

BTW, I doubt that a couple of other mails about vkernel stuff I sent ~2 weeks 
ago reached you. Is it your spam filtering setup being overjealous? I'm 
sending this mail both to you and the list so you can check (assuming you 
don't automatically delete duplicates).


[Date Prev][Date Next]  [Thread Prev][Thread Next]  [Date Index][Thread Index]