[S390] fix pgste update logic
The pgste_update_all / pgste_update_young and pgste_set_pte need to
check if the pte entry contains a valid page address before the storage
key can be accessed. In addition pgste_set_pte needs to set the access
key and fetch protection bit of the new pte entry, not the old entry.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h
index 34ede0e..524d23b 100644
--- a/arch/s390/include/asm/pgtable.h
+++ b/arch/s390/include/asm/pgtable.h
@@ -593,6 +593,8 @@
unsigned long address, bits;
unsigned char skey;
+ if (!pte_present(*ptep))
+ return pgste;
address = pte_val(*ptep) & PAGE_MASK;
skey = page_get_storage_key(address);
bits = skey & (_PAGE_CHANGED | _PAGE_REFERENCED);
@@ -625,6 +627,8 @@
#ifdef CONFIG_PGSTE
int young;
+ if (!pte_present(*ptep))
+ return pgste;
young = page_reset_referenced(pte_val(*ptep) & PAGE_MASK);
/* Transfer page referenced bit to pte software bit (host view) */
if (young || (pgste_val(pgste) & RCP_HR_BIT))
@@ -638,13 +642,15 @@
}
-static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste)
+static inline void pgste_set_pte(pte_t *ptep, pgste_t pgste, pte_t entry)
{
#ifdef CONFIG_PGSTE
unsigned long address;
unsigned long okey, nkey;
- address = pte_val(*ptep) & PAGE_MASK;
+ if (!pte_present(entry))
+ return;
+ address = pte_val(entry) & PAGE_MASK;
okey = nkey = page_get_storage_key(address);
nkey &= ~(_PAGE_ACC_BITS | _PAGE_FP_BIT);
/* Set page access key and fetch protection bit from pgste */
@@ -712,7 +718,7 @@
if (mm_has_pgste(mm)) {
pgste = pgste_get_lock(ptep);
- pgste_set_pte(ptep, pgste);
+ pgste_set_pte(ptep, pgste, entry);
*ptep = entry;
pgste_set_unlock(ptep, pgste);
} else