Support processors without unrestricted guest capability.

ok stefan

1 files changed, 34 insertions, 5 deletions

diff --git a/usr.sbin/vmd/loadfile_elf.c b/usr.sbin/vmd/loadfile_elf.c
index 10a5ad80d83..8d2e68b25b0 100644
--- a/usr.sbin/vmd/loadfile_elf.c
+++ b/usr.sbin/vmd/loadfile_elf.c
@@ -1,5 +1,5 @@
 /* $NetBSD: loadfile.c,v 1.10 2000/12/03 02:53:04 tsutsui Exp $ */
-/* $OpenBSD: loadfile_elf.c,v 1.12 2016/04/04 17:13:54 stefan Exp $ */
+/* $OpenBSD: loadfile_elf.c,v 1.13 2016/04/05 09:33:05 mlarkin Exp $ */
 
 /*-
  * Copyright (c) 1997 The NetBSD Foundation, Inc.
@@ -100,14 +100,11 @@
 #include <machine/vmmvar.h>
 #include <machine/biosvar.h>
 #include <machine/segments.h>
+#include <machine/pte.h>
 
 #include "loadfile.h"
 #include "vmd.h"
 
-#define BOOTARGS_PAGE 0x2000
-#define GDT_PAGE 0x10000
-#define STACK_PAGE 0xF000
-
 union {
 	Elf32_Ehdr elf32;
 	Elf64_Ehdr elf64;
@@ -195,6 +192,37 @@ push_gdt(void)
 }
 
 /*
+ * push_pt
+ *
+ * Create an identity-mapped page directory hierarchy mapping the first
+ * 1GB of physical memory. This is used during bootstrapping VMs on
+ * CPUs without unrestricted guest capability.
+ */
+static void
+push_pt(void)
+{
+	pt_entry_t ptes[NPTE_PG];
+	uint64_t i;
+
+	/* PML3 [0] - first 1GB */
+	memset(ptes, 0, sizeof(ptes));
+	ptes[0] = PG_V | PML3_PAGE;
+	write_mem(PML4_PAGE, ptes, PAGE_SIZE);
+
+	/* PML3 [0] - first 1GB */
+	memset(ptes, 0, sizeof(ptes));
+	ptes[0] = PG_V | PG_RW | PG_u | PML2_PAGE;
+	write_mem(PML3_PAGE, ptes, PAGE_SIZE);
+
+	/* PML2 [0..511] - first 1GB (in 2MB pages) */
+	memset(ptes, 0, sizeof(ptes));
+	for (i = 0 ; i < NPTE_PG; i++) {
+		ptes[i] = PG_V | PG_RW | PG_u | PG_PS | (NBPD_L2 * i);
+	}
+	write_mem(PML2_PAGE, ptes, PAGE_SIZE);
+}
+
+/*
  * loadelf_main
  *
  * Loads an ELF kernel to it's defined load address in the guest VM.
@@ -234,6 +262,7 @@ loadelf_main(int fd, struct vm_create_params *vcp, struct vcpu_init_state *vis)
 		return (r);
 
 	push_gdt();
+	push_pt();
 	n = create_bios_memmap(vcp, memmap);
 	bootargsz = push_bootargs(memmap, n);
 	stacksize = push_stack(bootargsz, marks[MARK_END]);