x86/mm/pat: Make set_memory_np() L1TF safe
authorAndi Kleen <ak@linux.intel.com>
Tue, 7 Aug 2018 22:09:39 +0000 (15:09 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 15 Aug 2018 16:13:01 +0000 (18:13 +0200)
commit 958f79b9ee55dfaf00c8106ed1c22a2919e0028b upstream

set_memory_np() is used to mark kernel mappings not present, but it has
it's own open coded mechanism which does not have the L1TF protection of
inverting the address bits.

Replace the open coded PTE manipulation with the L1TF protecting low level
PTE routines.

Passes the CPA self test.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/mm/pageattr.c

index 4085897fef648700f669fea03907828296076fb8..464f53da3a6f53f198d860b0bef0ce9c41db362f 100644 (file)
@@ -1006,8 +1006,8 @@ static long populate_pmd(struct cpa_data *cpa,
 
                pmd = pmd_offset(pud, start);
 
-               set_pmd(pmd, __pmd(cpa->pfn << PAGE_SHIFT | _PAGE_PSE |
-                                  massage_pgprot(pmd_pgprot)));
+               set_pmd(pmd, pmd_mkhuge(pfn_pmd(cpa->pfn,
+                                       canon_pgprot(pmd_pgprot))));
 
                start     += PMD_SIZE;
                cpa->pfn  += PMD_SIZE >> PAGE_SHIFT;
@@ -1079,8 +1079,8 @@ static int populate_pud(struct cpa_data *cpa, unsigned long start, p4d_t *p4d,
         * Map everything starting from the Gb boundary, possibly with 1G pages
         */
        while (boot_cpu_has(X86_FEATURE_GBPAGES) && end - start >= PUD_SIZE) {
-               set_pud(pud, __pud(cpa->pfn << PAGE_SHIFT | _PAGE_PSE |
-                                  massage_pgprot(pud_pgprot)));
+               set_pud(pud, pud_mkhuge(pfn_pud(cpa->pfn,
+                                  canon_pgprot(pud_pgprot))));
 
                start     += PUD_SIZE;
                cpa->pfn  += PUD_SIZE >> PAGE_SHIFT;