From d92fc69ccac4c0a20679fdbdc81b2010685a6f33 Mon Sep 17 00:00:00 2001 From: Andy Lutomirski Date: Thu, 14 Jul 2016 13:22:51 -0700 Subject: x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() kernel_unmap_pages_in_pgd() is dangerous: if a PGD entry in init_mm.pgd were to be cleared, callers would need to ensure that the pgd entry hadn't been propagated to any other pgd. Its only caller was efi_cleanup_page_tables(), and that, in turn, was unused, so just delete both functions. This leaves a couple of other helpers unused, so delete them, too. Signed-off-by: Andy Lutomirski Reviewed-by: Matt Fleming Acked-by: Borislav Petkov Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Josh Poimboeuf Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-efi@vger.kernel.org Link: http://lkml.kernel.org/r/77ff20fdde3b75cd393be5559ad8218870520248.1468527351.git.luto@kernel.org Signed-off-by: Ingo Molnar --- arch/x86/mm/pageattr.c | 28 ---------------------------- 1 file changed, 28 deletions(-) (limited to 'arch/x86/mm/pageattr.c') diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 26aa487ae4ef..26c93c6e04a0 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -746,18 +746,6 @@ static bool try_to_free_pmd_page(pmd_t *pmd) return true; } -static bool try_to_free_pud_page(pud_t *pud) -{ - int i; - - for (i = 0; i < PTRS_PER_PUD; i++) - if (!pud_none(pud[i])) - return false; - - free_page((unsigned long)pud); - return true; -} - static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end) { pte_t *pte = pte_offset_kernel(pmd, start); @@ -871,16 +859,6 @@ static void unmap_pud_range(pgd_t *pgd, unsigned long start, unsigned long end) */ } -static void unmap_pgd_range(pgd_t *root, unsigned long addr, unsigned long end) -{ - pgd_t *pgd_entry = root + pgd_index(addr); - - unmap_pud_range(pgd_entry, addr, end); - - if (try_to_free_pud_page((pud_t *)pgd_page_vaddr(*pgd_entry))) - pgd_clear(pgd_entry); -} - static int alloc_pte_page(pmd_t *pmd) { pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL | __GFP_NOTRACK); @@ -1994,12 +1972,6 @@ out: return retval; } -void kernel_unmap_pages_in_pgd(pgd_t *root, unsigned long address, - unsigned numpages) -{ - unmap_pgd_range(root, address, address + (numpages << PAGE_SHIFT)); -} - /* * The testcases use internal knowledge of the implementation that shouldn't * be exposed to the rest of the kernel. Include these directly here. -- cgit v1.2.3