> The commit d96885e277b5 ("parisc: use pgtable-nopXd instead of > 4level-fixup") converted PA-RISC to use folded page tables, but it missed > the conversion of pgd_populate() to pud_populate() in maps_pages() > function. This caused the upper page table directory to remain empty and > the system would crash as a result. > > Using pud_populate() that actually populates the page table instead of > dummy pgd_populate() fixes the issue. > ... > diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c > index ddca8287d43b..354cf060b67f 100644 > --- a/arch/parisc/mm/init.c > +++ b/arch/parisc/mm/init.c > @@ -401,7 +401,7 @@ static void __init map_pages(unsigned long start_vaddr, > pmd = (pmd_t *) __pa(pmd); > } > > - pgd_populate(NULL, pg_dir, __va(pmd)); > + pud_populate(NULL, (pud_t *)pg_dir, __va(pmd)); > #endif Wouldn't the untested patch below be more clean? Helge diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index ddca8287d43b..73de58f31f5f 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -387,6 +387,8 @@ static void __init map_pages(unsigned long start_vaddr, #if PTRS_PER_PMD == 1 pmd = (pmd_t *)__pa(pg_dir); #else + p4d_t *p4d; + pud_t *pud; pmd = (pmd_t *)pgd_address(*pg_dir); /* @@ -401,7 +403,9 @@ static void __init map_pages(unsigned long start_vaddr, pmd = (pmd_t *) __pa(pmd); } - pgd_populate(NULL, pg_dir, __va(pmd)); + p4d = p4d_offset(pg_dir, vaddr); + pud = pud_offset(p4d, vaddr); + pud_populate(NULL, pud, __va(pmd)); #endif pg_dir++;