From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Kirill A. Shutemov" , Ard Biesheuvel , Andrey Ryabinin , Baoquan He , Linus Torvalds , Matt Fleming , Peter Zijlstra , Thomas Gleixner , Ingo Molnar Subject: [PATCH 4.14 154/157] x86/efi: Fix efi_call_phys_epilog() with CONFIG_X86_5LEVEL=y Date: Sun, 1 Jul 2018 18:23:46 +0200 Message-Id: <20180701160900.950421999@linuxfoundation.org> In-Reply-To: <20180701160852.287307684@linuxfoundation.org> References: <20180701160852.287307684@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Kirill A. Shutemov commit cfe19577047e74cdac5826adbdc2337d8437f8fb upstream. Open-coded page table entry checks don't work correctly when we fold the page table level at runtime. pgd_present() on 4-level paging machine always returns true, but open-coded version of the check may return false-negative result and we silently skip the rest of the loop body in efi_call_phys_epilog(). Replace open-coded checks with proper helpers. Signed-off-by: Kirill A. Shutemov Acked-by: Ard Biesheuvel Cc: Andrey Ryabinin Cc: Baoquan He Cc: Linus Torvalds Cc: Matt Fleming Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: stable@vger.kernel.org # v4.12+ Fixes: 94133e46a0f5 ("x86/efi: Correct EFI identity mapping under 'efi=old_map' when KASLR is enabled") Link: http://lkml.kernel.org/r/20180625120852.18300-1-kirill.shutemov@linux.intel.com Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/platform/efi/efi_64.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/arch/x86/platform/efi/efi_64.c +++ b/arch/x86/platform/efi/efi_64.c @@ -166,14 +166,14 @@ void __init efi_call_phys_epilog(pgd_t * pgd = pgd_offset_k(pgd_idx * PGDIR_SIZE); set_pgd(pgd_offset_k(pgd_idx * PGDIR_SIZE), save_pgd[pgd_idx]); - if (!(pgd_val(*pgd) & _PAGE_PRESENT)) + if (!pgd_present(*pgd)) continue; for (i = 0; i < PTRS_PER_P4D; i++) { p4d = p4d_offset(pgd, pgd_idx * PGDIR_SIZE + i * P4D_SIZE); - if (!(p4d_val(*p4d) & _PAGE_PRESENT)) + if (!p4d_present(*p4d)) continue; pud = (pud_t *)p4d_page_vaddr(*p4d);