From: Dave Hansen <dave.han...@linux.intel.com>

In creating its page tables, the espfix code masks its PGTABLE_PROT
value with the supported mask: __supported_pte_mask.  This ensures
that unsupported bits are not set in the final PTE.  But, it also
sets _PAGE_GLOBAL which we do not want for PTE.  Use
__default_kernel_pte_mask instead which clears _PAGE_GLOBAL for PTI.

Signed-off-by: Dave Hansen <dave.han...@linux.intel.com>
Cc: Andrea Arcangeli <aarca...@redhat.com>
Cc: Andy Lutomirski <l...@kernel.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Kees Cook <keesc...@google.com>
Cc: Hugh Dickins <hu...@google.com>
Cc: Juergen Gross <jgr...@suse.com>
Cc: x...@kernel.org
Cc: Nadav Amit <na...@vmware.com>
---

 b/arch/x86/kernel/espfix_64.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff -puN arch/x86/kernel/espfix_64.c~espfix-use-kern-defaults-not-supported 
arch/x86/kernel/espfix_64.c
--- a/arch/x86/kernel/espfix_64.c~espfix-use-kern-defaults-not-supported        
2018-02-22 12:36:19.217036552 -0800
+++ b/arch/x86/kernel/espfix_64.c       2018-02-22 12:36:19.221036552 -0800
@@ -167,7 +167,7 @@ void init_espfix_ap(int cpu)
                goto unlock_done;
 
        node = cpu_to_node(cpu);
-       ptemask = __supported_pte_mask;
+       ptemask = __default_kernel_pte_mask;
 
        pud_p = &espfix_pud_page[pud_index(addr)];
        pud = *pud_p;
_

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