From mboxrd@z Thu Jan  1 00:00:00 1970
From: Helge Deller <deller@gmx.de>
Subject: [PATCH] parisc: ensure that mmapped shared pages are aligned at
 SHMLBA addresses
Date: Sun, 3 Feb 2013 00:44:59 +0100
Message-ID: <20130202234459.GD1188@p100.box>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
To: linux-parisc@vger.kernel.org,
	James Bottomley <James.Bottomley@HansenPartnership.com>,
	John David Anglin <dave.anglin@bell.net>
Return-path: <linux-parisc-owner@vger.kernel.org>
List-ID: <linux-parisc.vger.kernel.org>
List-Id: linux-parisc.vger.kernel.org

Author: John David Anglin <dave.anglin@bell.net>

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

diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c
index f76c108..a047b32 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;