[src/netbsd-6]: src/sys/arch/i386/i386 Pull up following revision(s) (request...

[riz <riz%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/6ce4b104aede
branches:  netbsd-6
changeset: 773792:6ce4b104aede
user:      riz <riz%NetBSD.org@localhost>
date:      Wed Feb 22 19:07:12 2012 +0000

description:
Pull up following revision(s) (requested by bouyer in ticket #32):
        sys/arch/i386/i386/machdep.c: revision 1.719
i386_switch_context(): mimic code in cpu_switchto() and compare pcb->pcb_fpcpu
against ci to decide if we need to turn off FPU. Fix FPU corruption, e.g.
paranoia occasionally reporting flaws on Xen/MP systems.
XXX is ci_fpused still needed at all ?

diffstat:

 sys/arch/i386/i386/machdep.c |  7 +++----
 1 files changed, 3 insertions(+), 4 deletions(-)

diffs (29 lines):

diff -r 43d8a0926c1d -r 6ce4b104aede sys/arch/i386/i386/machdep.c
--- a/sys/arch/i386/i386/machdep.c      Wed Feb 22 18:59:05 2012 +0000
+++ b/sys/arch/i386/i386/machdep.c      Wed Feb 22 19:07:12 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: machdep.c,v 1.717 2012/01/12 19:49:37 cherry Exp $     */
+/*     $NetBSD: machdep.c,v 1.717.2.1 2012/02/22 19:07:12 riz Exp $    */
 
 /*-
  * Copyright (c) 1996, 1997, 1998, 2000, 2004, 2006, 2008, 2009
@@ -67,7 +67,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.717 2012/01/12 19:49:37 cherry Exp $");
+__KERNEL_RCSID(0, "$NetBSD: machdep.c,v 1.717.2.1 2012/02/22 19:07:12 riz Exp $");
 
 #include "opt_beep.h"
 #include "opt_compat_ibcs2.h"
@@ -544,9 +544,8 @@
 
        pcb = lwp_getpcb(l);
        ci = curcpu();
-       if (ci->ci_fpused) {
+       if (pcb->pcb_fpcpu != ci) {
                HYPERVISOR_fpu_taskswitch(1);
-               ci->ci_fpused = 0;
        }
 
        HYPERVISOR_stack_switch(GSEL(GDATA_SEL, SEL_KPL), pcb->pcb_esp0);