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Date: Wed, 11 Feb 2009 19:15:08 +0530
Message-ID: <251d650c0902110545w7c521e66tcb74f8ecc83e17a1@mail.gmail.com>
From: Mehul Chadha <mehulc87@gmail.com>
To: freebsd-hackers@freebsd.org
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Subject: understanding of PTD symbol
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Hello all,
               I am having doubts in understanding the usage of the
symbol PTD. Could anyone pls explain the usage of PTD in the FreeBSD
kernel??

In pmap_growkernel when we execute the following instruction wht is
returned by pdir_pde ? Is it the physical address of a page table for
KVA addressing??

                   while (pdir_pde(PTD, kernel_vm_end))

When I used objdump on the kernel executable i found the address of
PTD symbol to be 0xBFEFF000 , I could not understand this , as in a
virtual memory with 1G/3G split the kernel addressing must be between
the addresses 0xC0000000 and 0xFFFFFFFF.

Regards,
Mehul