svn commit: r216847 - in head/sys/i386: i386 include

[Colin Percival]

Author: cperciva
Date: Fri Dec 31 17:42:25 2010
New Revision: 216847
URL: http://svn.freebsd.org/changeset/base/216847

Log:
  Make i386_set_ldt work on i386/XEN, step 5/5.
  
  When cleaning up a thread, reset its LDT to the default LDT.
  
  Note: Casting the LDT pointer to an int and storing it in pc_currentldt is
  wildly bogus, but is harmless since pc_currentldt is a write-only variable.
  
  MFC after:	3 days

Modified:
  head/sys/i386/i386/sys_machdep.c
  head/sys/i386/include/segments.h

Modified: head/sys/i386/i386/sys_machdep.c
==============================================================================
--- head/sys/i386/i386/sys_machdep.c	Fri Dec 31 17:41:14 2010	(r216846)
+++ head/sys/i386/i386/sys_machdep.c	Fri Dec 31 17:42:25 2010	(r216847)
@@ -523,8 +523,13 @@ user_ldt_free(struct thread *td)
 	}
 
 	if (td == PCPU_GET(curthread)) {
+#ifdef XEN
+		i386_reset_ldt(&default_proc_ldt);
+		PCPU_SET(currentldt, (int)&default_proc_ldt);
+#else
 		lldt(_default_ldt);
 		PCPU_SET(currentldt, _default_ldt);
+#endif
 	}
 
 	mdp->md_ldt = NULL;

Modified: head/sys/i386/include/segments.h
==============================================================================
--- head/sys/i386/include/segments.h	Fri Dec 31 17:41:14 2010	(r216846)
+++ head/sys/i386/include/segments.h	Fri Dec 31 17:42:25 2010	(r216847)
@@ -257,6 +257,7 @@ struct region_descriptor {
 #ifdef _KERNEL
 extern int	_default_ldt;
 #ifdef XEN
+extern struct proc_ldt default_proc_ldt;
 extern union descriptor *gdt;
 extern union descriptor *ldt;
 #else