From owner-svn-src-all@FreeBSD.ORG  Mon Oct 13 16:14:21 2008
Return-Path: <owner-svn-src-all@FreeBSD.ORG>
Delivered-To: svn-src-all@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 920841065686;
	Mon, 13 Oct 2008 16:14:21 +0000 (UTC) (envelope-from jhb@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id 7FE268FC12;
	Mon, 13 Oct 2008 16:14:21 +0000 (UTC) (envelope-from jhb@FreeBSD.org)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id m9DGELD0080223;
	Mon, 13 Oct 2008 16:14:21 GMT (envelope-from jhb@svn.freebsd.org)
Received: (from jhb@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id m9DGELBG080222;
	Mon, 13 Oct 2008 16:14:21 GMT (envelope-from jhb@svn.freebsd.org)
Message-Id: <200810131614.m9DGELBG080222@svn.freebsd.org>
From: John Baldwin <jhb@FreeBSD.org>
Date: Mon, 13 Oct 2008 16:14:21 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-stable@freebsd.org, svn-src-stable-7@freebsd.org
X-SVN-Group: stable-7
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r183823 - in stable/7/sys: . boot/i386/libi386
X-BeenThere: svn-src-all@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the entire src tree \(except for &quot;
	user&quot; and &quot; projects&quot; \)" <svn-src-all.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-all>
List-Post: <mailto:svn-src-all@freebsd.org>
List-Help: <mailto:svn-src-all-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-all>,
	<mailto:svn-src-all-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 13 Oct 2008 16:14:21 -0000

Author: jhb
Date: Mon Oct 13 16:14:21 2008
New Revision: 183823
URL: http://svn.freebsd.org/changeset/base/183823

Log:
  MFC: Fail requests to boot an amd64 kernel on an i386-only CPU.
  
  Approved by:	re (kib)

Modified:
  stable/7/sys/   (props changed)
  stable/7/sys/boot/i386/libi386/bootinfo64.c

Modified: stable/7/sys/boot/i386/libi386/bootinfo64.c
==============================================================================
--- stable/7/sys/boot/i386/libi386/bootinfo64.c	Mon Oct 13 14:05:01 2008	(r183822)
+++ stable/7/sys/boot/i386/libi386/bootinfo64.c	Mon Oct 13 16:14:21 2008	(r183823)
@@ -32,6 +32,9 @@ __FBSDID("$FreeBSD$");
 #include <sys/reboot.h>
 #include <sys/linker.h>
 #include <machine/bootinfo.h>
+#include <machine/cpufunc.h>
+#include <machine/psl.h>
+#include <machine/specialreg.h>
 #include "bootstrap.h"
 #include "libi386.h"
 #include "btxv86.h"
@@ -124,7 +127,45 @@ bi_copymodules64(vm_offset_t addr)
 }
 
 /*
- * Load the information expected by an i386 kernel.
+ * Check to see if this CPU supports long mode.
+ */
+static int
+bi_checkcpu(void)
+{
+    char *cpu_vendor;
+    int vendor[3];
+    int eflags, regs[4];
+
+    /* Check for presence of "cpuid". */
+    eflags = read_eflags();
+    write_eflags(eflags ^ PSL_ID);
+    if (!((eflags ^ read_eflags()) & PSL_ID))
+	return (0);
+
+    /* Fetch the vendor string. */
+    do_cpuid(0, regs);
+    vendor[0] = regs[1];
+    vendor[1] = regs[3];
+    vendor[2] = regs[2];
+    cpu_vendor = (char *)vendor;
+
+    /* Check for vendors that support AMD features. */
+    if (strncmp(cpu_vendor, "GenuineIntel", 12) != 0 &&
+	strncmp(cpu_vendor, "AuthenticAMD", 12) != 0)
+	return (0);
+
+    /* Has to support AMD features. */
+    do_cpuid(0x80000000, regs);
+    if (!(regs[0] >= 0x80000001))
+	return (0);
+
+    /* Check for long mode. */
+    do_cpuid(0x80000001, regs);
+    return (regs[3] & AMDID_LM);
+}
+
+/*
+ * Load the information expected by an amd64 kernel.
  *
  * - The 'boothowto' argument is constructed
  * - The 'bootdev' argument is constructed
@@ -145,6 +186,11 @@ bi_load64(char *args, vm_offset_t *modul
     char			*rootdevname;
     int				howto;
 
+    if (!bi_checkcpu()) {
+	printf("CPU doesn't support long mode\n");
+	return (EINVAL);
+    }
+
     howto = bi_getboothowto(args);
 
     /*