How to get the PTE pointer for a linear address?

From: Peter Teoh
Date: Fri Oct 17 2008 - 03:07:28 EST

If I allocate kernel memory via alloc_page(GFP_KERNEL), and convert
that struct page pointer to linear address via page_address(), how do
I derive the PTE pointer of that page?

Following the source code, I did the following:

pgd_t *pgd = pgd_offset_k(address);

if (pgd_none(*pgd)) {
printk("no pgd ");
return 0;
pud = pud_offset(pgd, address);
if (pud_none(*pud)) {
printk("no pud ");
return 0;
pmd = pmd_offset(pud, address);
if (pmd_none(*pmd)) {
printk("no pmd ");
return 0;

pte = pte_offset_map(pmd, address);

===============> and in between here, the PTE pointer is returned
(from pte_offset_map())? And so the PTE structure (pte_t) should be


I suspect something is not right?

Peter Teoh
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