Kernel panic with ACPI enabled

John Baldwin jhb at
Wed Feb 8 07:37:19 PST 2006

On Wednesday 08 February 2006 04:33, Peter Jeremy wrote:
> On Tue, 2006-Feb-07 23:59:06 -0800, Nate Lawson wrote:
> >John Baldwin wrote:
> >>Actually, in his case I'm fairly sure MAXMEM is the problem.  Several
> >>people have had problems trying to use the tunable equivalent
> >>(hw.physmem=3g and the like) because if the new maxmem value is greater
> >
> >Can we at least put a printf() in the boot sequence that says "warning:
> >maxmem set and acpi enabled, this may cause problems"?  This keeps
> >coming up.
> Presumably this isn't a problem where hw.physmem is used to artifically
> reduce the system for testing.

It depends on the value you use.  Some values will be ok, some will break 
things.  The code that handles maxmem and physmem really needs to be 
SMAP-aware and not use memory that we know isn't really memory.

John Baldwin <jhb at>  <><
"Power Users Use the Power to Serve"  =

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