svn commit: r268952 - stable/10/sys/amd64/vmm

[John Baldwin]

Author: jhb
Date: Mon Jul 21 18:26:51 2014
New Revision: 268952
URL: http://svnweb.freebsd.org/changeset/base/268952

Log:
  MFC 264347:
  Account for the "plus 1" encoding of the CPUID Function 4 reported
  core per package and cache sharing values.

Modified:
  stable/10/sys/amd64/vmm/x86.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/amd64/vmm/x86.c
==============================================================================
--- stable/10/sys/amd64/vmm/x86.c	Mon Jul 21 18:23:48 2014	(r268951)
+++ stable/10/sys/amd64/vmm/x86.c	Mon Jul 21 18:26:51 2014	(r268952)
@@ -219,9 +219,18 @@ x86_emulate_cpuid(struct vm *vm, int vcp
 
 			/*
 			 * Do not expose topology.
+			 *
+			 * The maximum number of processor cores in
+			 * this physical processor package and the
+			 * maximum number of threads sharing this
+			 * cache are encoded with "plus 1" encoding.
+			 * Adding one to the value in this register
+			 * field to obtains the actual value.
+			 *
+			 * Therefore 0 for both indicates 1 core per
+			 * package and no cache sharing.
 			 */
 			regs[0] &= 0xffff8000;
-			regs[0] |= 0x04008000;
 			break;
 
 		case CPUID_0000_0007: