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x86/mm/pat: Make set_memory_np() L1TF safe
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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>
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Andi Kleen authored and Thomas Gleixner committed Aug 8, 2018
1 parent 0768f91 commit 958f79b
Showing 1 changed file with 4 additions and 4 deletions.
8 changes: 4 additions & 4 deletions arch/x86/mm/pageattr.c
Original file line number Diff line number Diff line change
Expand Up @@ -1014,8 +1014,8 @@ 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;
Expand Down Expand Up @@ -1087,8 +1087,8 @@ 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;
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