Support processors without unrestricted guest capability.

ok stefan

3 files changed, 49 insertions, 9 deletions

diff --git a/usr.sbin/vmd/loadfile.h b/usr.sbin/vmd/loadfile.h
index 4b473425550..19534e09683 100644
--- a/usr.sbin/vmd/loadfile.h
+++ b/usr.sbin/vmd/loadfile.h
@@ -1,5 +1,5 @@
 /*	$NetBSD: loadfile.h,v 1.1 1999/04/28 09:08:50 christos Exp $	 */
-/*	$OpenBSD: loadfile.h,v 1.3 2016/03/13 13:11:47 stefan Exp $	 */
+/*	$OpenBSD: loadfile.h,v 1.4 2016/04/05 09:33:05 mlarkin Exp $	 */
 
 /*-
  * Copyright (c) 1998 The NetBSD Foundation, Inc.
@@ -65,6 +65,14 @@
 
 #define LOWMEM_KB 636
 
+#define BOOTARGS_PAGE 0x2000
+#define STACK_PAGE 0xF000
+#define GDT_PAGE 0x10000
+#define PML4_PAGE 0x11000
+#define PML3_PAGE 0x12000
+#define PML2_PAGE 0x13000
+#define NPTE_PG (PAGE_SIZE / sizeof(pt_entry_t))
+
 int loadelf_main(int, struct vm_create_params *,
     struct vcpu_init_state *);
 
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]);
diff --git a/usr.sbin/vmd/vmm.c b/usr.sbin/vmd/vmm.c
index 521a08beb7f..8c7eddf2df7 100644
--- a/usr.sbin/vmd/vmm.c
+++ b/usr.sbin/vmd/vmm.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmm.c,v 1.24 2016/04/04 17:13:54 stefan Exp $	*/
+/*	$OpenBSD: vmm.c,v 1.25 2016/04/05 09:33:05 mlarkin Exp $	*/
 
 /*
  * Copyright (c) 2015 Mike Larkin <mlarkin@openbsd.org>
@@ -161,13 +161,16 @@ static struct privsep_proc procs[] = {
  *
  * Specific bootloaders should clone this structure and override
  * those fields as needed.
+ *
+ * Note - CR3 and various bits in CR0 may be overridden by vmm(4) based on
+ *        features of the CPU in use.
  */
 static const struct vcpu_init_state vcpu_init_flat32 = {
 	0x2,					/* RFLAGS */
 	0x0,					/* RIP */
 	0x0,					/* RSP */
-	CR0_CD | CR0_NW | CR0_ET | CR0_PE,	/* CR0 */
-	0x0,					/* CR3 */
+	CR0_CD | CR0_NW | CR0_ET | CR0_PE | CR0_PG, /* CR0 */
+	PML4_PAGE,				/* CR3 */
 	{ 0x8, 0xFFFFFFFF, 0xC09F, 0x0},	/* CS */
 	{ 0x10, 0xFFFFFFFF, 0xC093, 0x0},	/* DS */
 	{ 0x10, 0xFFFFFFFF, 0xC093, 0x0},	/* ES */