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charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/13/26 06:55, Yeoreum Yun wrote: > @@ -134,11 +129,12 @@ static inline void resume_init_first_level_page_table(pgd_t *pg_dir) > { > #ifdef CONFIG_X86_PAE > int i; > + pud_t *pud = pud_offset(p4d_offset(pg_dir, 0), 0); > > /* Init entries of the first-level page table to the zero page */ > for (i = 0; i < PTRS_PER_PGD; i++) > - set_pgd(pg_dir + i, > - __pgd(__pa(empty_zero_page) | _PAGE_PRESENT)); > + set_pud(pud + i, > + __pud(__pa(empty_zero_page) | _PAGE_PRESENT)); > #endif > } If this is the way forward, it's going to require the retraining of some awfully old brain cells. It also doesn't really read correctly. Loop over each PGD entry: for (i = 0; i < PTRS_PER_PGD; i++) ... and set a pud? set_pud(...) I'm not sure how I'd ever learn the rules to write this code from scratch. Right now, the code says: "The pgd_t is the top level of the page tables. I know there are PTRS_PER_PGD of those top level entries entries I need to 'zero'." You don't have to know what is folded, just that you're dealing with the top level. But *this* code says: 1. The pgd_t is the top level of the page tables. Start there. 2. "Walk" down *two* (folded) levels 3. Set the third-level (pud) entries to 'zero' So the code now *has* to know how the folding occurs. This seems really hard to work with to me.