Merge pull request #40 from bobuhiro11/refactoring

flag, ebda: refactoring code

Makefile

@@ -39,8 +39,7 @@ bzImage: linux.config linux.tar.xz
 
 .PHONY: run
 run: initrd bzImage
-	# refs: commit 1621292e73770aabbc146e72036de5e26f901e86 in kvmtool
-	go run . -p "console=ttyS0 earlyprintk=serial noapic noacpi notsc debug apic=debug show_lapic=all mitigations=off lapic dyndbg=\"file arch/x86/kernel/smpboot.c +plf\"" -c 4
+	go run . -c 4
 
 .PHONY: run-system-kernel
 run-system-kernel:

ebda/ebda.go

@@ -3,6 +3,7 @@ package ebda
 import (
 	"bytes"
 	"encoding/binary"
+	"fmt"
 	"unsafe"
 
 	"github.com/bobuhiro11/gokvm/bootparam"
@@ -12,6 +13,8 @@ const (
 	MaxVCPUs = 64
 )
 
+var errorVCPUNumExceed = fmt.Errorf("the number of vCPUs must be less than or equal to %d", MaxVCPUs)
+
 // Extended BIOS Data Area (EBDA).
 type EBDA struct {
 	// padding
@@ -146,6 +149,10 @@ func NewMPCTable(nCPUs int) (*MPCTable, error) {
 	m.LAPIC = apicAddr(0)
 	m.OEMCount = MaxVCPUs // This must be the number of entries
 
+	if nCPUs > MaxVCPUs {
+		return nil, errorVCPUNumExceed
+	}
+
 	var err error
 
 	for i := 0; i < nCPUs; i++ {

flag/flag.go

@@ -7,9 +7,13 @@ import (
 func ParseArgs(args []string) (string, string, string, int, error) {
 	kernel := flag.String("k", "./bzImage", "kernel image path")
 	initrd := flag.String("i", "./initrd", "initrd path")
-	params := flag.String("p", "console=ttyS0", "kernel command-line parameters")
 	nCpus := flag.Int("c", 1, "number of cpus")
 
+	//  refs: commit 1621292e73770aabbc146e72036de5e26f901e86 in kvmtool
+	params := flag.String("p", `console=ttyS0 earlyprintk=serial noapic noacpi notsc `+
+		`debug apic=debug show_lapic=all mitigations=off lapic `+
+		`dyndbg="file arch/x86/kernel/smpboot.c +plf"`, "kernel command-line parameters")
+
 	flag.Parse()
 
 	if err := flag.CommandLine.Parse(args[1:]); err != nil {