s390/vdso: fix access-list entry initialization
authorHeiko Carstens <heiko.carstens@de.ibm.com>
Sat, 30 Nov 2013 11:57:13 +0000 (12:57 +0100)
committerMartin Schwidefsky <schwidefsky@de.ibm.com>
Mon, 2 Dec 2013 14:31:09 +0000 (15:31 +0100)
The access-list entry is supposed to have the fetch-only bit set, however
a reserved bit got set instead.
Userspace isn't able to write to the page anyway since the accessed page
has the read-only bit set. So this saves us only for bad surprises in the
future if the reserved bit gets used.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
arch/s390/kernel/vdso.c

index a84476f2a9bb3ae488eb7a936021a744a822dd31..613649096783401e0cf9acf73069dff48a35e438 100644 (file)
@@ -125,7 +125,7 @@ int vdso_alloc_per_cpu(struct _lowcore *lowcore)
                psal[i] = 0x80000000;
 
        lowcore->paste[4] = (u32)(addr_t) psal;
-       psal[0] = 0x20000000;
+       psal[0] = 0x02000000;
        psal[2] = (u32)(addr_t) aste;
        *(unsigned long *) (aste + 2) = segment_table +
                _ASCE_TABLE_LENGTH + _ASCE_USER_BITS + _ASCE_TYPE_SEGMENT;