From owner-svn-src-head@FreeBSD.ORG  Mon Jan 20 18:37:35 2014
Return-Path: <owner-svn-src-head@FreeBSD.ORG>
Delivered-To: svn-src-head@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115])
 (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id 8E119BF7;
 Mon, 20 Jan 2014 18:37:35 +0000 (UTC)
Received: from svn.freebsd.org (svn.freebsd.org
 [IPv6:2001:1900:2254:2068::e6a:0])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (No client certificate requested)
 by mx1.freebsd.org (Postfix) with ESMTPS id 7A57F1D8E;
 Mon, 20 Jan 2014 18:37:35 +0000 (UTC)
Received: from svn.freebsd.org ([127.0.1.70])
 by svn.freebsd.org (8.14.7/8.14.7) with ESMTP id s0KIbZfc012461;
 Mon, 20 Jan 2014 18:37:35 GMT (envelope-from marcel@svn.freebsd.org)
Received: (from marcel@localhost)
 by svn.freebsd.org (8.14.7/8.14.7/Submit) id s0KIbZGY012460;
 Mon, 20 Jan 2014 18:37:35 GMT (envelope-from marcel@svn.freebsd.org)
Message-Id: <201401201837.s0KIbZGY012460@svn.freebsd.org>
From: Marcel Moolenaar <marcel@FreeBSD.org>
Date: Mon, 20 Jan 2014 18:37:35 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: svn commit: r260914 - head/sys/ia64/ia64
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
 <svn-src-head.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head/>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
 <mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 20 Jan 2014 18:37:35 -0000

Author: marcel
Date: Mon Jan 20 18:37:35 2014
New Revision: 260914
URL: http://svnweb.freebsd.org/changeset/base/260914

Log:
  In pmap_set_pte(), make sure to enforce ordering by inserting a memory
  fence. Under system load, the CPU has been found to change the order
  by which the stores are made visible. When the tag is made visible
  before the other TLB values, other CPUs may use the invalid TLB values
  and do bad things.
  
  While here (i.e. not a fix) don't return errors from pmap_remove_vhpt()
  to callers of pmap_remove_pte(). Those callers don't check the return
  value and as such don't do what is needed to keep a consistent state.
  More importantly, pmap_remove_vhpt() can't really have an error without
  it indicating something unintended. Using KASSERT is therefore better.
  
  PR:		182999, 183227

Modified:
  head/sys/ia64/ia64/pmap.c

Modified: head/sys/ia64/ia64/pmap.c
==============================================================================
--- head/sys/ia64/ia64/pmap.c	Mon Jan 20 18:15:06 2014	(r260913)
+++ head/sys/ia64/ia64/pmap.c	Mon Jan 20 18:37:35 2014	(r260914)
@@ -1303,6 +1303,8 @@ pmap_set_pte(struct ia64_lpte *pte, vm_o
 
 	pte->itir = PAGE_SHIFT << 2;
 
+	ia64_mf();
+
 	pte->tag = ia64_ttag(va);
 }
 
@@ -1321,8 +1323,8 @@ pmap_remove_pte(pmap_t pmap, struct ia64
 	 * First remove from the VHPT.
 	 */
 	error = pmap_remove_vhpt(va);
-	if (error)
-		return (error);
+	KASSERT(error == 0, ("%s: pmap_remove_vhpt returned %d",
+	    __func__, error));
 
 	pmap_invalidate_page(va);