From: Joerg Roedel <jroe...@suse.de>

There it is also usable from 32 bit code.

Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
 arch/x86/include/asm/pgtable.h | 23 +++++++++++++++++++++++
 1 file changed, 23 insertions(+)

diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index eb47432..cc117161 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -640,8 +640,31 @@ static inline int is_new_memtype_allowed(u64 paddr, 
unsigned long size,
 
 pmd_t *populate_extra_pmd(unsigned long vaddr);
 pte_t *populate_extra_pte(unsigned long vaddr);
+
+#ifdef CONFIG_PAGE_TABLE_ISOLATION
+pgd_t __pti_set_user_pgtbl(pgd_t *pgdp, pgd_t pgd);
+
+/*
+ * Take a PGD location (pgdp) and a pgd value that needs to be set there.
+ * Populates the user and returns the resulting PGD that must be set in
+ * the kernel copy of the page tables.
+ */
+static inline pgd_t pti_set_user_pgtbl(pgd_t *pgdp, pgd_t pgd)
+{
+       if (!static_cpu_has(X86_FEATURE_PTI))
+               return pgd;
+       return __pti_set_user_pgtbl(pgdp, pgd);
+}
+#else   /* CONFIG_PAGE_TABLE_ISOLATION */
+static inline pgd_t pti_set_user_pgtbl(pgd_t *pgdp, pgd_t pgd)
+{
+       return pgd;
+}
+#endif  /* CONFIG_PAGE_TABLE_ISOLATION */
+
 #endif /* __ASSEMBLY__ */
 
+
 #ifdef CONFIG_X86_32
 # include <asm/pgtable_32.h>
 #else
-- 
2.7.4

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