diff --git a/conf/i386.rmk b/conf/i386.rmk
index c9ba18b11..690194261 100644
--- a/conf/i386.rmk
+++ b/conf/i386.rmk
@@ -84,23 +84,32 @@ kfreebsd.init.i386: $(srcdir)/tests/boot/kfreebsd.init-i386.S
 knetbsd.init.i386: $(srcdir)/tests/boot/knetbsd.init-i386.S
 	$(TARGET_CC) -o $@ $< -m32 -nostdlib -nostdinc -DSUCCESSFUL_BOOT_STRING=\"$(SUCCESSFUL_BOOT_STRING)\"
 
+knetbsd.init.x86_64: $(srcdir)/tests/boot/knetbsd.init-x86_64.S
+	$(TARGET_CC) -o $@ $< -m64 -nostdlib -nostdinc -DSUCCESSFUL_BOOT_STRING=\"$(SUCCESSFUL_BOOT_STRING)\"
+
 linux-initramfs.%: linux.init.%
 	TDIR=`mktemp -d`; cp $< $$TDIR/init; (cd $$TDIR; echo ./init | cpio --quiet --dereference -o -H newc) | gzip > $@; rm -rf $$TDIR
 
 kfreebsd-mfsroot.%: kfreebsd.init.%
-	TDIR=`mktemp -d`; mkdir $$TDIR/dev; mkdir $$TDIR/sbin; cp $< $$TDIR/sbin/init; makefs -t ffs -s 30m -f 1000 -o minfree=0,version=1 $@ $$TDIR; rm -rf $$TDIR
+	TDIR=`mktemp -d`; mkdir $$TDIR/dev; mkdir $$TDIR/sbin; cp $< $$TDIR/sbin/init; makefs -t ffs -s 64k -f 10 -o minfree=0,version=1 $@ $$TDIR; rm -rf $$TDIR
 
 knetbsd.image.%: knetbsd.init.%
-	TDIR=`mktemp -d` && mkdir $$TDIR/dev && mkdir $$TDIR/sbin && cp $< $$TDIR/sbin/init && makefs -t ffs -s 30m -f 1000 -o minfree=0,version=1 $@ $$TDIR && rm -rf $$TDIR
+	TDIR=`mktemp -d` && mkdir $$TDIR/dev && mkdir $$TDIR/sbin && cp $< $$TDIR/sbin/init && makefs -t ffs -s 64k -f 10 -o minfree=0,version=1 $@ $$TDIR && rm -rf $$TDIR
 
 knetbsd.miniroot-image.i386: knetbsd.image.i386 $(GRUB_PAYLOADS_DIR)/knetbsd.miniroot.i386
 	$(OBJCOPY) --add-section=miniroot=$< $(GRUB_PAYLOADS_DIR)/knetbsd.miniroot.i386 $@
 
+knetbsd.miniroot-image.x86_64: knetbsd.image.x86_64 $(GRUB_PAYLOADS_DIR)/knetbsd.miniroot.x86_64
+	$(OBJCOPY) --add-section=miniroot=$< $(GRUB_PAYLOADS_DIR)/knetbsd.miniroot.x86_64 $@
+
 CLEANFILES += linux.init.i386 kfreebsd.init.i386 linux.init.x86_64 linux-initramfs.i386 linux-initramfs.x86_64
 
 bootcheck-knetbsd-i386: knetbsd.miniroot-image.i386 $(GRUB_PAYLOADS_DIR)/knetbsd.i386 $(srcdir)/tests/boot/knetbsd.cfg knetbsd.miniroot-image.i386 grub-shell
 	timeout -s KILL $(BOOTCHECK_TIMEOUT) ./grub-shell --boot=$(BOOTTARGET) --qemu=qemu-system-i386 --files=/miniroot=knetbsd.miniroot-image.i386 --files=/knetbsd=$(GRUB_PAYLOADS_DIR)/knetbsd.i386 $(srcdir)/tests/boot/knetbsd.cfg | grep $(SUCCESSFUL_BOOT_STRING) > /dev/null
 
+bootcheck-knetbsd-x86_64: knetbsd.miniroot-image.x86_64 $(GRUB_PAYLOADS_DIR)/knetbsd.x86_64 $(srcdir)/tests/boot/knetbsd.cfg knetbsd.miniroot-image.x86_64 grub-shell
+	timeout -s KILL $(BOOTCHECK_TIMEOUT) ./grub-shell --boot=$(BOOTTARGET) --qemu=qemu-system-x86_64 --files=/miniroot=knetbsd.miniroot-image.x86_64 --files=/knetbsd=$(GRUB_PAYLOADS_DIR)/knetbsd.x86_64 $(srcdir)/tests/boot/knetbsd.cfg | grep $(SUCCESSFUL_BOOT_STRING) > /dev/null
+
 bootcheck-kfreebsd-i386: kfreebsd-mfsroot.i386 $(GRUB_PAYLOADS_DIR)/kfreebsd.i386 $(GRUB_PAYLOADS_DIR)/kfreebsd_env.i386 $(srcdir)/tests/boot/kfreebsd.cfg grub-shell
 	timeout -s KILL $(BOOTCHECK_TIMEOUT) ./grub-shell --boot=$(BOOTTARGET) --qemu=qemu-system-i386 --files=/mfsroot=kfreebsd-mfsroot.i386 --files=/kfreebsd=$(GRUB_PAYLOADS_DIR)/kfreebsd.i386 --files=/kfreebsd_env=$(GRUB_PAYLOADS_DIR)/kfreebsd_env.i386 $(srcdir)/tests/boot/kfreebsd.cfg | grep $(SUCCESSFUL_BOOT_STRING) > /dev/null
 
@@ -115,8 +124,8 @@ bootcheck-linux-x86_64: linux-initramfs.x86_64 $(GRUB_PAYLOADS_DIR)/linux.x86_64
 
 BOOTCHECKS+=bootcheck-linux-i386 bootcheck-linux-x86_64 \
 	bootcheck-kfreebsd-i386 bootcheck-kfreebsd-x86_64 \
-	bootcheck-knetbsd-i386
+	bootcheck-knetbsd-i386 bootcheck-knetbsd-x86_64
 
 .PHONY: bootcheck-linux-i386 bootcheck-linux-x86_64 \
-	bootcheck-kfreebsd-i386 bootcheck-kfreebsd-x86_64
-	bootcheck-knetbsd-i386
\ No newline at end of file
+	bootcheck-kfreebsd-i386 bootcheck-kfreebsd-x86_64 \
+	bootcheck-knetbsd-i386 bootcheck-knetbsd-x86_64
diff --git a/tests/boot/knetbsd.init-x86_64.S b/tests/boot/knetbsd.init-x86_64.S
new file mode 100644
index 000000000..e56174f9c
--- /dev/null
+++ b/tests/boot/knetbsd.init-x86_64.S
@@ -0,0 +1,124 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2010  Free Software Foundation, Inc.
+ *
+ *  GRUB is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  GRUB is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define MODE_RDRW 2
+#define FLAGS_NONE 0
+#define SYSCALL_OPEN 5
+#define SYSCALL_WRITE 4
+#define SYSCALL_RESET 208
+#define SYSCALL_EXIT 1
+#define SYSCALL_MKNOD 14
+#define SYSCALL_MOUNT 410
+#define SYSCALL_INT 0x80
+
+#define RESET_NOSYNC 0x4
+#define RESET_HALT 0x8
+#define RESET_POWEROFF 0x800
+
+	.section ".init", "ax"
+	.global start,_start
+start:
+_start:
+	/* mount.  */
+	movq $SYSCALL_MOUNT, %rax
+	movq $devfstype, %rdi
+	movq $devfsdir, %rsi
+	movq $0, %rdx
+	movq $tmpfs_args, %r10
+	movq $(tmpfs_args_end - tmpfs_args), %r8
+	syscall
+
+	/* mknod.  */
+	movq $SYSCALL_MKNOD, %rax
+	leaq device, %rdi
+	movq $0x2140, %rsi
+	movq $0, %rdx
+	syscall
+
+	/* open.  */
+	movq $SYSCALL_OPEN, %rax
+	leaq device, %rdi
+	movq $MODE_RDRW, %rsi
+	movq $FLAGS_NONE, %rdx
+	syscall
+	movq %rax, %rdi
+
+	/* write.  */
+	movq $SYSCALL_WRITE, %rax
+	movq $(messageend-message), %rdx
+	leaq message, %rsi
+	syscall
+
+	/* shutdown.  */
+	movq $SYSCALL_RESET, %rax
+	movq $(RESET_POWEROFF|RESET_HALT|RESET_NOSYNC), %rdi
+	movq $haltmsg, %rsi
+	syscall
+
+	/* exit (1). Shouldn't be reached.  */
+	movq $SYSCALL_EXIT, %rax
+	movq $1, %rdi
+	syscall
+	.section ".fini", "ax"
+1:	jmp 1b
+	.section ".text", "ax"
+1:	jmp 1b
+	/* This section is needed for NetBSD to identify the binary.  */
+	.section ".note.netbsd.ident", "a"
+	.long 0x7
+	.long 0x4
+	.long 0x1
+	.ascii "NetBSD"
+	.byte 0
+	.data
+device:
+	.ascii "/dev/console"
+	.byte 0
+message:
+	.ascii "Boot Test Passed Successfully\n" SUCCESSFUL_BOOT_STRING "\n"
+messageend:
+haltmsg:
+	.ascii "Machine halted"
+	.byte 0
+devfstype:
+	.ascii "tmpfs"
+	.byte 0
+devfsdir:
+	.ascii "/dev"
+	.byte 0
+tmpfs_args:
+	/* Version.  */
+	.long 1
+
+	/* Alignment long.  */
+	.long 0
+
+	/* Maximum inodes.  */
+	.quad 	0
+	/* Maximum size.  */
+	.quad   0
+
+	/* UID */
+	.long		0
+	/* GID */
+	.long 		0
+	/* Mode */
+	.long		0777
+	/* Alignment long.  */
+	.long 0
+tmpfs_args_end:	
\ No newline at end of file