From: Oscar Salvador <osalvador@xxxxxxx> Subject: x86/vmemmap: drop handling of 1GB vmemmap ranges There is no code to allocate 1GB pages when mapping the vmemmap range as this might waste some memory and requires more complexity which is not really worth. Drop the dead code both for the aligned and unaligned cases and leave only the direct map handling. Link: https://lkml.kernel.org/r/20210309214050.4674-3-osalvador@xxxxxxx Signed-off-by: Oscar Salvador <osalvador@xxxxxxx> Suggested-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Acked-by: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: "H . Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Zi Yan <ziy@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/x86/mm/init_64.c | 35 +++++++---------------------------- 1 file changed, 7 insertions(+), 28 deletions(-) --- a/arch/x86/mm/init_64.c~x86-vmemmap-drop-handling-of-1gb-vmemmap-ranges +++ a/arch/x86/mm/init_64.c @@ -1062,7 +1062,6 @@ remove_pud_table(pud_t *pud_start, unsig unsigned long next, pages = 0; pmd_t *pmd_base; pud_t *pud; - void *page_addr; pud = pud_start + pud_index(addr); for (; addr < end; addr = next, pud++) { @@ -1071,33 +1070,13 @@ remove_pud_table(pud_t *pud_start, unsig if (!pud_present(*pud)) continue; - if (pud_large(*pud)) { - if (IS_ALIGNED(addr, PUD_SIZE) && - IS_ALIGNED(next, PUD_SIZE)) { - if (!direct) - free_pagetable(pud_page(*pud), - get_order(PUD_SIZE)); - - spin_lock(&init_mm.page_table_lock); - pud_clear(pud); - spin_unlock(&init_mm.page_table_lock); - pages++; - } else { - /* If here, we are freeing vmemmap pages. */ - memset((void *)addr, PAGE_INUSE, next - addr); - - page_addr = page_address(pud_page(*pud)); - if (!memchr_inv(page_addr, PAGE_INUSE, - PUD_SIZE)) { - free_pagetable(pud_page(*pud), - get_order(PUD_SIZE)); - - spin_lock(&init_mm.page_table_lock); - pud_clear(pud); - spin_unlock(&init_mm.page_table_lock); - } - } - + if (pud_large(*pud) && + IS_ALIGNED(addr, PUD_SIZE) && + IS_ALIGNED(next, PUD_SIZE)) { + spin_lock(&init_mm.page_table_lock); + pud_clear(pud); + spin_unlock(&init_mm.page_table_lock); + pages++; continue; } _
