[ipxe-devel] question about memory in ipxe

Michael Brown mbrown at fensystems.co.uk
Mon Aug 13 14:36:15 UTC 2012

> On Sat, Aug 11, 2012 at 3:24 AM, Michael Brown <mbrown at fensystems.co.uk>
> wrote:
>> Allocating memory with umalloc() changes the system memory map as
>> reported by
>> INT 15,e820.  It is therefore not allowed to allocate memory with
>> umalloc()
>> from routines that may be called by external code such as a PXE NBP.
> If I only intend to run iPXE using chainloading,
> is it safe to increase the size of the heap to say
> a couple to tens of megabytes?

The method used to run iPXE doesn't matter here; it's what you instruct
iPXE to do that counts.  If you ask iPXE (chainloaded or ROM-loaded) to
perform a SAN boot, then all memory claimed by iPXE (including any unused
heap space) will be unusable until the machine is next rebooted.


More information about the ipxe-devel mailing list