parisc: ensure that mmapped shared pages are aligned at SHMLBA addresses

Signed-off-by: John David Anglin <dave.anglin@bell.net>
Signed-off-by: Helge Deller <deller@gmx.de>

arch/parisc/kernel/sys_parisc.c

@@ -94,11 +94,12 @@ unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
 {
 	if (len > TASK_SIZE)
 		return -ENOMEM;
-	/* Might want to check for cache aliasing issues for MAP_FIXED case
-	 * like ARM or MIPS ??? --BenH.
-	 */
-	if (flags & MAP_FIXED)
+	if (flags & MAP_FIXED) {
+		if ((flags & MAP_SHARED) &&
+		    (addr - (pgoff << PAGE_SHIFT)) & (SHMLBA - 1))
+			return -EINVAL;
 		return addr;
+	}
 	if (!addr)
 		addr = TASK_UNMAPPED_BASE;