svn commit: r304958 - head/sys/i386/i386

[Bruce Evans]

Author: bde
Date: Sun Aug 28 15:23:44 2016
New Revision: 304958
URL: https://svnweb.freebsd.org/changeset/base/304958

Log:
  Fix vm86 initialization, part 1 of 2 and a half.
  
  Early use of vm86 depends on the PIC being reset to mask interrupts,
  but r286667 moved PIC initialization to after where vm86 may be first
  used.
  
  Move the PIC initialization up to immdiately before vm86 initialization.
  All invocations of diff that I tried display this move poorly so that it
  looks like PIC and vm86 initialization was moved later.
  
  r286667 was to move console initialization later.  The diffs are again
  unreadable -- they show a large move that doesn't seem to involve the
  console.  The PIC initialization stayed just below the console
  initialization where it could still be debugged but no longer works.
  
  Later console initialization breaks mainly debugging vm86 initialization
  and memory sizing using ddb and printf().  There are several printf()s
  in the memory sizing that now go nowhere since message buffer
  initialization has always been too late.  Memory sizing is done by loader
  for most users, but the lost messages for this case are even more
  interesting than for an auto-probe since they tell you what the loader
  found.

Modified:
  head/sys/i386/i386/machdep.c

Modified: head/sys/i386/i386/machdep.c
==============================================================================
--- head/sys/i386/i386/machdep.c	Sun Aug 28 14:03:25 2016	(r304957)
+++ head/sys/i386/i386/machdep.c	Sun Aug 28 15:23:44 2016	(r304958)
@@ -2646,20 +2646,7 @@ init386(first)
 	PCPU_SET(common_tss.tss_ioopt, (sizeof (struct i386tss)) << 16);
 	ltr(gsel_tss);
 
-	vm86_initialize();
-	getmemsize(first);
-	init_param2(physmem);
-
-	/* now running on new page tables, configured,and u/iom is accessible */
-
-	/*
-	 * Initialize the console before we print anything out.
-	 */
-	cninit();
-
-	if (metadata_missing)
-		printf("WARNING: loader(8) metadata is missing!\n");
-
+	/* Initialize the PIC early for vm86 calls. */
 #ifdef DEV_ISA
 #ifdef DEV_ATPIC
 #ifndef PC98
@@ -2681,6 +2668,20 @@ init386(first)
 #endif
 #endif
 
+	vm86_initialize();
+	getmemsize(first);
+	init_param2(physmem);
+
+	/* now running on new page tables, configured,and u/iom is accessible */
+
+	/*
+	 * Initialize the console before we print anything out.
+	 */
+	cninit();
+
+	if (metadata_missing)
+		printf("WARNING: loader(8) metadata is missing!\n");
+
 #ifdef DDB
 	db_fetch_ksymtab(bootinfo.bi_symtab, bootinfo.bi_esymtab);
 #endif