diff options
| author | Christian Borntraeger <borntraeger@de.ibm.com> | 2013-05-27 16:19:55 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2013-05-28 15:18:05 +0200 |
| commit | b56433cb782d1cc7e44fc46d2ce3917fa75d2236 (patch) | |
| tree | 4ef2bf321a213f0c5ad70c2967a2c5b94a82a8a5 /arch/s390 | |
| parent | d5b4c2f4938aaebc392669111385c3cf50dd309f (diff) | |
s390/pgtable: Fix check for pgste/storage key handling
pte_present might return true on PAGE_TYPE_NONE, even if
the invalid bit is on. Modify the existing check of the
pgste functions to avoid crashes.
[ Martin Schwidefsky: added ptep_modify_prot_[start|commit] bits ]
Reported-by: Martin Schwidefky <schwidefsky@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
CC: stable@vger.kernel.org
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 0f0de30e3e3..ac01463038f 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -646,7 +646,7 @@ static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste) unsigned long address, bits; unsigned char skey; - if (!pte_present(*ptep)) + if (pte_val(*ptep) & _PAGE_INVALID) return pgste; address = pte_val(*ptep) & PAGE_MASK; skey = page_get_storage_key(address); @@ -680,7 +680,7 @@ static inline pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste) #ifdef CONFIG_PGSTE int young; - if (!pte_present(*ptep)) + if (pte_val(*ptep) & _PAGE_INVALID) return pgste; /* Get referenced bit from storage key */ young = page_reset_referenced(pte_val(*ptep) & PAGE_MASK); @@ -706,7 +706,7 @@ static inline void pgste_set_key(pte_t *ptep, pgste_t pgste, pte_t entry) unsigned long address; unsigned long okey, nkey; - if (!pte_present(entry)) + if (pte_val(entry) & _PAGE_INVALID) return; address = pte_val(entry) & PAGE_MASK; okey = nkey = page_get_storage_key(address); @@ -1098,6 +1098,9 @@ static inline pte_t ptep_modify_prot_start(struct mm_struct *mm, pte = *ptep; if (!mm_exclusive(mm)) __ptep_ipte(address, ptep); + + if (mm_has_pgste(mm)) + pgste = pgste_update_all(&pte, pgste); return pte; } @@ -1105,9 +1108,13 @@ static inline void ptep_modify_prot_commit(struct mm_struct *mm, unsigned long address, pte_t *ptep, pte_t pte) { + pgste_t pgste; + if (mm_has_pgste(mm)) { + pgste = *(pgste_t *)(ptep + PTRS_PER_PTE); + pgste_set_key(ptep, pgste, pte); pgste_set_pte(ptep, pte); - pgste_set_unlock(ptep, *(pgste_t *)(ptep + PTRS_PER_PTE)); + pgste_set_unlock(ptep, pgste); } else *ptep = pte; } |