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Re: ddb 'step' recovers from a page fault

On Fri, May 16, 2008 at 01:00:04PM -0500, David Young wrote:
> I am seeing "recoverable" page fault traps in ether_output().  What I
> mean by "recoverable" is that if I type 'continue' at the ddb prompt,
> the fault does not re-occur!  In the console log, below, I have typed
> 'step' instead of 'continue' at the debugger prompt.  Note that after
> the 'step', esp and ss registers have changed from outlandish numbers
> (esp 0xc0743240, ss 0x2) to normal numbers (0xc6d427a4, 0x10).

New datapoint: it looks to me like most the vm_map_entry's in the kernel
map are not "wired," and the map itself is marked pageable.  That is, most
of the entries wired counts are 0, and the kernel map flag VM_MAP_PAGEABLE
is set.  The unwired entries include entries covering the kernel text
and data.  Is it possible that the kernel is trying to swap kernel pages?
(Swap is off!)


David Young             OJC Technologies      Urbana, IL * (217) 278-3933 ext 24

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