powerpc/mm: Fix _PAGE_CHG_MASK to protect _PAGE_SPECIAL
Fix _PAGE_CHG_MASK so that pte_modify() does not affect the _PAGE_SPECIAL bit.
Signed-off-by: Philippe Gerum <rpm@xenomai.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/pgtable-4k.h b/arch/powerpc/include/asm/pgtable-4k.h
index 6b18ba9..1dbca4e7 100644
--- a/arch/powerpc/include/asm/pgtable-4k.h
+++ b/arch/powerpc/include/asm/pgtable-4k.h
@@ -60,7 +60,7 @@
/* It should be preserving the high 48 bits and then specifically */
/* preserving _PAGE_SECONDARY | _PAGE_GROUP_IX */
#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY | \
- _PAGE_HPTEFLAGS)
+ _PAGE_HPTEFLAGS | _PAGE_SPECIAL)
/* Bits to mask out from a PMD to get to the PTE page */
#define PMD_MASKED_BITS 0
diff --git a/arch/powerpc/include/asm/pgtable-64k.h b/arch/powerpc/include/asm/pgtable-64k.h
index 07b0d8f..7389003 100644
--- a/arch/powerpc/include/asm/pgtable-64k.h
+++ b/arch/powerpc/include/asm/pgtable-64k.h
@@ -114,7 +114,7 @@
* pgprot changes
*/
#define _PAGE_CHG_MASK (PTE_RPN_MASK | _PAGE_HPTEFLAGS | _PAGE_DIRTY | \
- _PAGE_ACCESSED)
+ _PAGE_ACCESSED | _PAGE_SPECIAL)
/* Bits to mask out from a PMD to get to the PTE page */
#define PMD_MASKED_BITS 0x1ff
diff --git a/arch/powerpc/include/asm/pgtable-ppc32.h b/arch/powerpc/include/asm/pgtable-ppc32.h
index f69a4d9..820b5f0 100644
--- a/arch/powerpc/include/asm/pgtable-ppc32.h
+++ b/arch/powerpc/include/asm/pgtable-ppc32.h
@@ -429,7 +429,8 @@
#define PMD_PAGE_SIZE(pmd) bad_call_to_PMD_PAGE_SIZE()
#endif
-#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
+#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY | \
+ _PAGE_SPECIAL)
#define PAGE_PROT_BITS (_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \