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| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2011-11-14 11:19:00 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2011-11-14 11:19:08 +0100 |
| commit | 09b538833b85521d937a06faf61e6a3273253cc0 (patch) | |
| tree | f1d66c7dfd425b1efd3cce1ab8d9c38fe30beee1 /arch/s390 | |
| parent | 800252976be89611ef86d6d04442a821018ed949 (diff) | |
| download | lwn-09b538833b85521d937a06faf61e6a3273253cc0.tar.gz lwn-09b538833b85521d937a06faf61e6a3273253cc0.zip | |
[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>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/include/asm/pgtable.h | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 34ede0ea85a9..524d23b8610c 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -593,6 +593,8 @@ static inline pgste_t pgste_update_all(pte_t *ptep, pgste_t pgste) 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 @@ static inline pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste) #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 pgste_t pgste_update_young(pte_t *ptep, pgste_t pgste) } -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 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr, 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 |