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| author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2018-06-25 15:08:52 +0300 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2018-06-27 09:52:52 +0200 |
| commit | cfe19577047e74cdac5826adbdc2337d8437f8fb (patch) | |
| tree | 0af3b1c1ceea7bf3af1073bbd21978f36fc28adc /arch | |
| parent | e8a445dea219c32727016af14f847d2e8f7ebec8 (diff) | |
| download | linux-cfe19577047e74cdac5826adbdc2337d8437f8fb.tar.bz2 | |
x86/efi: Fix efi_call_phys_epilog() with CONFIG_X86_5LEVEL=y
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 <kirill.shutemov@linux.intel.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
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 <mingo@kernel.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/platform/efi/efi_64.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/platform/efi/efi_64.c b/arch/x86/platform/efi/efi_64.c index e01f7ceb9e7a..77873ce700ae 100644 --- 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 *save_pgd) 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); |