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>

1 files changed, 5 insertions, 4 deletions

diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index f76c10863c62..a047b3227e50 100644
--- a/arch/parisc/kernel/sys_parisc.c
+++ b/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;