svn commit: r342145 - stable/12/sys/i386/i386

[Konstantin Belousov]

Author: kib
Date: Sun Dec 16 02:30:55 2018
New Revision: 342145
URL: https://svnweb.freebsd.org/changeset/base/342145

Log:
  MFC r341746:
  Fix PAE boot.

Modified:
  stable/12/sys/i386/i386/mpboot.s
Directory Properties:
  stable/12/   (props changed)

Modified: stable/12/sys/i386/i386/mpboot.s
==============================================================================
--- stable/12/sys/i386/i386/mpboot.s	Sun Dec 16 01:51:38 2018	(r342144)
+++ stable/12/sys/i386/i386/mpboot.s	Sun Dec 16 02:30:55 2018	(r342145)
@@ -99,6 +99,20 @@ NON_GPROF_ENTRY(MPentry)
 	movl	%cr4, %eax
 	orl	$CR4_PAE, %eax
 	movl	%eax, %cr4
+	movl	$0x80000000, %eax
+	cpuid
+	movl	$0x80000001, %ebx
+	cmpl	%ebx, %eax
+	jb	1f
+	movl	%ebx, %eax
+	cpuid
+	testl	$AMDID_NX, %edx
+	je	1f
+	movl	$MSR_EFER, %ecx
+	rdmsr
+	orl	$EFER_NXE,%eax
+	wrmsr
+1:
 #else
 	movl	IdlePTD, %eax
 	movl	%eax,%cr3