There used to be a dependency on _PAGE_PRIVILEGED with pte_savedwrite.
But that got dropped by
commit 6a56ccbcf6c6 ("mm/autonuma: use can_change_(pte|pmd)_writable() to
replace savedwrite")
With this change numa fault pte (pte_protnone()) gets mapped as regular user pte
with RWX cleared (no-access). This also remove pte_user() from
book3s/64.
pte_access_permitted() now checks for _PAGE_EXEC because we now support
EXECONLY mappings.
Signed-off-by: Aneesh Kumar K.V <aneesh.ku...@linux.ibm.com>
---
arch/powerpc/include/asm/book3s/64/pgtable.h | 23 +++++---------------
arch/powerpc/mm/book3s64/hash_utils.c | 17 +++++++++++++++
2 files changed, 23 insertions(+), 17 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h
b/arch/powerpc/include/asm/book3s/64/pgtable.h
index cb77eddca54b..7c7de7b56df0 100644
--- a/arch/powerpc/include/asm/book3s/64/pgtable.h
+++ b/arch/powerpc/include/asm/book3s/64/pgtable.h
@@ -17,12 +17,6 @@
#define _PAGE_EXEC 0x00001 /* execute permission */
#define _PAGE_WRITE 0x00002 /* write access allowed */
#define _PAGE_READ 0x00004 /* read access allowed */
-#define _PAGE_NA _PAGE_PRIVILEGED
-#define _PAGE_NAX _PAGE_EXEC
-#define _PAGE_RO _PAGE_READ
-#define _PAGE_ROX (_PAGE_READ | _PAGE_EXEC)
-#define _PAGE_RW (_PAGE_READ | _PAGE_WRITE)
-#define _PAGE_RWX (_PAGE_READ | _PAGE_WRITE | _PAGE_EXEC)
#define _PAGE_PRIVILEGED 0x00008 /* kernel access only */
#define _PAGE_SAO 0x00010 /* Strong access order */
#define _PAGE_NON_IDEMPOTENT 0x00020 /* non idempotent memory */
@@ -119,9 +113,9 @@
/*
* user access blocked by key
*/
-#define _PAGE_KERNEL_RW (_PAGE_PRIVILEGED | _PAGE_RW |
_PAGE_DIRTY)
#define _PAGE_KERNEL_RO (_PAGE_PRIVILEGED | _PAGE_READ)
#define _PAGE_KERNEL_ROX (_PAGE_PRIVILEGED | _PAGE_READ | _PAGE_EXEC)
+#define _PAGE_KERNEL_RW (_PAGE_PRIVILEGED | _PAGE_RW |
_PAGE_DIRTY)
#define _PAGE_KERNEL_RWX (_PAGE_PRIVILEGED | _PAGE_DIRTY | _PAGE_RW |
_PAGE_EXEC)
/*
* _PAGE_CHG_MASK masks of bits that are to be preserved across
@@ -523,19 +517,14 @@ static inline bool arch_pte_access_permitted(u64 pte,
bool write, bool execute)
}
#endif /* CONFIG_PPC_MEM_KEYS */
-static inline bool pte_user(pte_t pte)
-{
- return !(pte_raw(pte) & cpu_to_be64(_PAGE_PRIVILEGED));
-}
-
#define pte_access_permitted pte_access_permitted
static inline bool pte_access_permitted(pte_t pte, bool write)
{
- /*
- * _PAGE_READ is needed for any access and will be
- * cleared for PROT_NONE
- */
- if (!pte_present(pte) || !pte_user(pte) || !pte_read(pte))
+
+ if (!pte_present(pte))
+ return false;
+
+ if (!(pte_read(pte) || pte_exec(pte)))
return false;
if (write && !pte_write(pte))
diff --git a/arch/powerpc/mm/book3s64/hash_utils.c
b/arch/powerpc/mm/book3s64/hash_utils.c
index ad2afa08e62e..b2eda22195f0 100644
--- a/arch/powerpc/mm/book3s64/hash_utils.c
+++ b/arch/powerpc/mm/book3s64/hash_utils.c
@@ -310,9 +310,26 @@ unsigned long htab_convert_pte_flags(unsigned long
pteflags, unsigned long flags
else
rflags |= 0x3;
}
+ WARN_ON(!(pteflags & _PAGE_RWX));
} else {
if (pteflags & _PAGE_RWX)
rflags |= 0x2;
+ else {
+ /*
+ * PAGE_NONE will get mapped to 0b110 (slb key 1 no
access)
+ * We picked 0b110 instead of 0b000 so that slb key 0
will
+ * get only read only access for the same rflags.
+ */
+ if (mmu_has_feature(MMU_FTR_KERNEL_RO))
+ rflags |= (HPTE_R_PP0 | 0x2);
+ /*
+ * rflags = HPTE_R_N
+ * Without KERNEL_RO feature this will result in slb
+ * key 0 with read/write. But ISA only supports that.
+ * There is no key 1 no-access and key 0 read-only
+ * pp bit support.
+ */
+ }
if (!((pteflags & _PAGE_WRITE) && (pteflags & _PAGE_DIRTY)))
rflags |= 0x1;
}
--
2.41.0
