Patch "x86/mm/dump_pagetables: Check PAGE_PRESENT for real" has been added to the 4.14-stable tree

Patch "x86/mm/dump_pagetables: Check PAGE_PRESENT for real" has been added to the 4.14-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    x86/mm/dump_pagetables: Check PAGE_PRESENT for real

to the 4.14-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     x86-mm-dump_pagetables-check-page_present-for-real.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c05344947b37f7cda726e802457370bc6eac4d26 Mon Sep 17 00:00:00 2001
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sat, 16 Dec 2017 01:14:39 +0100
Subject: x86/mm/dump_pagetables: Check PAGE_PRESENT for real

From: Thomas Gleixner <tglx@linutronix.de>

commit c05344947b37f7cda726e802457370bc6eac4d26 upstream.

The check for a present page in printk_prot():

       if (!pgprot_val(prot)) {
                /* Not present */

is bogus. If a PTE is set to PAGE_NONE then the pgprot_val is not zero and
the entry is decoded in bogus ways, e.g. as RX GLB. That is confusing when
analyzing mapping correctness. Check for the present bit to make an
informed decision.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/x86/mm/dump_pagetables.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/mm/dump_pagetables.c
+++ b/arch/x86/mm/dump_pagetables.c
@@ -140,7 +140,7 @@ static void printk_prot(struct seq_file
 	static const char * const level_name[] =
 		{ "cr3", "pgd", "p4d", "pud", "pmd", "pte" };
 
-	if (!pgprot_val(prot)) {
+	if (!(pr & _PAGE_PRESENT)) {
 		/* Not present */
 		pt_dump_cont_printf(m, dmsg, "                              ");
 	} else {


Patches currently in stable-queue which might be from tglx@linutronix.de are

queue-4.14/x86-entry-rename-sysenter_stack-to-cpu_entry_area_entry_stack.patch
queue-4.14/x86-mm-put-mmu-to-hardware-asid-translation-in-one-place.patch
queue-4.14/x86-vsyscall-64-explicitly-set-_page_user-in-the-pagetable-hierarchy.patch
queue-4.14/x86-uv-use-the-right-tlb-flush-api.patch
queue-4.14/x86-decoder-fix-and-update-the-opcodes-map.patch
queue-4.14/x86-mm-dump_pagetables-check-page_present-for-real.patch
queue-4.14/x86-ldt-prevent-ldt-inheritance-on-exec.patch
queue-4.14/x86-microcode-dont-abuse-the-tlb-flush-interface.patch
queue-4.14/x86-doc-remove-obvious-weirdnesses-from-the-x86-mm-layout-documentation.patch
queue-4.14/init-invoke-init_espfix_bsp-from-mm_init.patch
queue-4.14/x86-cpu_entry_area-move-it-to-a-separate-unit.patch
queue-4.14/x86-vsyscall-64-warn-and-fail-vsyscall-emulation-in-native-mode.patch
queue-4.14/x86-mm-create-asm-invpcid.h.patch
queue-4.14/x86-cpu_entry_area-prevent-wraparound-in-setup_cpu_entry_area_ptes-on-32bit.patch
queue-4.14/x86-mm-remove-superfluous-barriers.patch
queue-4.14/x86-ldt-rework-locking.patch
queue-4.14/pci-pm-force-devices-to-d0-in-pci_pm_thaw_noirq.patch
queue-4.14/arch-mm-allow-arch_dup_mmap-to-fail.patch
queue-4.14/x86-cpu_entry_area-move-it-out-of-the-fixmap.patch
queue-4.14/tools-headers-sync-objtool-uapi-header.patch
queue-4.14/x86-mm-remove-hard-coded-asid-limit-checks.patch
queue-4.14/x86-kconfig-limit-nr_cpus-on-32-bit-to-a-sane-amount.patch
queue-4.14/objtool-fix-64-bit-build-on-32-bit-host.patch
queue-4.14/x86-mm-add-comments-to-clarify-which-tlb-flush-functions-are-supposed-to-flush-what.patch
queue-4.14/x86-mm-move-the-cr3-construction-functions-to-tlbflush.h.patch
queue-4.14/x86-mm-dump_pagetables-make-the-address-hints-correct-and-readable.patch
queue-4.14/x86-insn-eval-add-utility-functions-to-get-segment-selector.patch
queue-4.14/objtool-move-synced-files-to-their-original-relative-locations.patch
queue-4.14/x86-mm-use-__flush_tlb_one-for-kernel-memory.patch
queue-4.14/objtool-move-kernel-headers-code-sync-check-to-a-script.patch
queue-4.14/x86-mm-64-improve-the-memory-map-documentation.patch
queue-4.14/objtool-fix-cross-build.patch