Excerpts from Russell King - ARM Linux admin's message of February 2, 2021 9:13 pm: > On Tue, Feb 02, 2021 at 09:05:02PM +1000, Nicholas Piggin wrote: >> diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h >> index c02f24400369..d63a5bb6bd0c 100644 >> --- a/arch/arm/include/asm/pgtable.h >> +++ b/arch/arm/include/asm/pgtable.h >> @@ -166,6 +166,9 @@ extern struct page *empty_zero_page; >> >> extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; >> >> +#define pud_page(pud) pmd_page(__pmd(pud_val(pud))) >> +#define pud_write(pud) pmd_write(__pmd(pud_val(pud))) > > As there is no PUD, does it really make sense to return a valid > struct page (which will be the PTE page) for pud_page(), which is > several tables above? There is no PUD on 3-level either, and the pgtable-nopud.h which it uses also passes down p4d_page to pud_page, so by convention... Although in this case at least for my next patch it won't acutally use pud_page unless it's a leaf entry so maybe it shouldn't get called anyway. Thanks, Nick