svn commit: r333524 - head/sys/i386/i386

[Konstantin Belousov]

Author: kib
Date: Sat May 12 10:57:34 2018
New Revision: 333524
URL: https://svnweb.freebsd.org/changeset/base/333524

Log:
  Initialize tramp_idleptd during cold pmap startup, before the
  exception code is copied to the trampoline.
  
  The correct value is then copied to trampoline automatically, so
  tramp_idleptd_reloced can be eliminated.
  
  This will allow to use the same exception entry code to handle traps
  from vm86 bios calls on early boot stage, as after the trampoline is
  configured.
  
  Sponsored by:	The FreeBSD Foundation

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

Modified: head/sys/i386/i386/machdep.c
==============================================================================
--- head/sys/i386/i386/machdep.c	Sat May 12 10:51:50 2018	(r333523)
+++ head/sys/i386/i386/machdep.c	Sat May 12 10:57:34 2018	(r333524)
@@ -2508,15 +2508,12 @@ init386(int first)
 	return ((register_t)thread0.td_pcb);
 }
 
-extern u_int tramp_idleptd;
-
 static void
 machdep_init_trampoline(void)
 {
 	struct region_descriptor r_gdt, r_idt;
 	struct i386tss *tss;
 	char *copyout_buf, *trampoline, *tramp_stack_base;
-	u_int *tramp_idleptd_reloced;
 	int x;
 
 	gdt = pmap_trm_alloc(sizeof(union descriptor) * NGDT * mp_ncpus,
@@ -2553,14 +2550,6 @@ machdep_init_trampoline(void)
 	/* Re-initialize new IDT since the handlers were relocated */
 	setidt_disp = trampoline - start_exceptions;
 	fixup_idt();
-
-	tramp_idleptd_reloced = (u_int *)((uintptr_t)&tramp_idleptd +
-	    setidt_disp);
-#if defined(PAE) || defined(PAE_TABLES)
-	*tramp_idleptd_reloced = (u_int)IdlePDPT;
-#else
-	*tramp_idleptd_reloced = (u_int)IdlePTD;
-#endif
 
 	r_idt.rd_limit = sizeof(struct gate_descriptor) * NIDT - 1;
 	r_idt.rd_base = (int)idt;

Modified: head/sys/i386/i386/pmap.c
==============================================================================
--- head/sys/i386/i386/pmap.c	Sat May 12 10:51:50 2018	(r333523)
+++ head/sys/i386/i386/pmap.c	Sat May 12 10:57:34 2018	(r333524)
@@ -366,6 +366,7 @@ pdpt_entry_t *IdlePDPT;	/* phys addr of kernel PDPT */
 #endif
 pt_entry_t *KPTmap;	/* address of kernel page tables */
 u_long KPTphys;		/* phys addr of kernel page tables */
+extern u_long tramp_idleptd;
 
 static u_long
 allocpages(u_int cnt, u_long *physfree)
@@ -531,6 +532,7 @@ pmap_cold(void)
 #else
 	cr3 = (u_int)IdlePTD;
 #endif
+	tramp_idleptd = cr3;
 	load_cr3(cr3);
 	load_cr0(rcr0() | CR0_PG);