linux C 错误 :segmentation fault(core dumped)

[pan__yy]

#include<stdio.h>
#include<stdlib.h>
#include<malloc.h>
#include <unistd.h>
//#include <windows.h>
#define N 6
enum STATE{ready, run, finish}STATE;

// 待插入就绪队列的进程数据
int id[N]       = { 0,  1,  2,  3,  4,  5 };
int priority[N] = { 9, 38, 17,  2,  7, 18 };
int cpuTime[N]  = { 0,  0,  0,  0,  0,  0 };
int allTime[N]  = { 3,  2,  3,  6,  1,  3 };
	
typedef struct PCB{
	int pid;
	int priority;
	int cpuTime;
	int allTime; 
	int state;
	struct PCB *next;
}PCB;
typedef struct{
	PCB *head;
	PCB *tail;
	PCB *maxPriority;
}linkQueue;

linkQueue readyQueue;

void initQueue(){
	int maxm = -1;
	int i;
	PCB *head, *tail, *p;
	readyQueue.head = readyQueue.tail = (PCB *)malloc(sizeof(PCB));
	head->next=NULL;
	for(i=0;i<N;i++){
		p = (PCB *)malloc(sizeof(PCB));
		p->pid = id[i];
		p->priority = priority[i];
		p->cpuTime = cpuTime[i];
		p->allTime = allTime[i];
		p->state = ready;
		p->next = NULL;
		readyQueue.tail->next = p;
		readyQueue.tail = p;
		if(priority[i] > maxm){
			readyQueue.maxPriority = p;
			maxm = priority[i];
		}

	}

	return;
}

/* 查看正在运行进程的信息 */
void runningProcess(PCB *p){
	printf("-------------------------------Running--------------------------------\n");
	printf("Pid=%d\tPriority=%d\tCpuTime=%d\tAllTime=%d\tState=running\n", p->pid, p->priority, p->cpuTime, p->allTime);
	printf("----------------------------------------------------------------------\n");
	return;	
}


/*  查看就绪队列的信息  */
void readyQueCheck(){
	PCB *p = readyQueue.head->next;
//	printf("\n%d\n", readyQueue.tail->pid);
	printf("-------------------------------Ready----------------------------------\n");
	if(p == NULL) 
		printf("Ready queue is empty!\n");
	while(p != NULL){
		printf("Pid=%d\tPriority=%d\tCpuTime=%d\tAllTime=%d\tState=ready\n", p->pid, p->priority, p->cpuTime, p->allTime);
		p = p->next;
	}
	printf("----------------------------------------------------------------------\n");

}

void enQueue(PCB *p){
	readyQueue.tail->next = p;
	readyQueue.tail = p;
	p->next = NULL;
	return;
}

/* 让指定的进程出列 */
void popQueue(PCB *p){
	if(readyQueue.head->next != NULL){
		PCB *temp = readyQueue.head;
		while(temp!=NULL){
			if(temp->next == p){
				temp->next = p->next;
				p->next = NULL;
				if(temp->next==NULL)
					readyQueue.tail = temp;
				return;		
			}
			temp = temp->next;		
		}
		printf("Process not found!\n");
	} else{
		printf("Queue is empty!\n");
	}
	return;
}

/* 更新就绪队列最大优先权进程 */
void updateMaxPriority(){
	PCB *p;
	int maxm = -1;
	p = readyQueue.head->next;
	while(p != NULL){
		if(p->priority > maxm){
			readyQueue.maxPriority = p;
			maxm = p->priority;
		}
		p = p->next;
	}
	return;
}



void timeSlice(){
	popQueue(readyQueue.maxPriority);
	PCB *p = readyQueue.head->next;
	runningProcess(readyQueue.maxPriority);
	readyQueCheck();
	readyQueue.maxPriority->priority = readyQueue.maxPriority->priority-3;
	readyQueue.maxPriority->cpuTime++;
	readyQueue.maxPriority->allTime--;
	readyQueue.maxPriority->state = run;
	while(p != NULL){
		p->priority++;
		p = p->next;
	}
	if(readyQueue.maxPriority->allTime != 0){
		enQueue(readyQueue.maxPriority);	
	} else {
		free(readyQueue.maxPriority);
	}
	updateMaxPriority();
}



/* 检查队列是否为空 */
int isEmpty(linkQueue q){
	if(q.head->next == NULL)
		return 1;
	return 0;
} 

int main()
{
	int slices=0;
	initQueue();
	printf("CPU RUNNING：\n");
//	Sleep(500);
	while(!isEmpty(readyQueue)){
		slices++;
		timeSlice();
//		Sleep(300);
	}
	printf("All processes finished! Using %d timelices\n", slices);
	return 0;
}

程序功能：模拟动态优先权算法
在windows下能正常运行，在centos6.6下就报错 :segmentation fault(core dumped)了，调了一天都不知道是怎么回事，求大神帮帮忙，

[LubinLew]

36 行，head是随机值，使用head->next 就是访问了非法地址

[paschen]

出错时断下来，通过调用堆栈、变量窗口等观察分析原因

[赵4老师]

进程意外退出会在当前目录下产生‘core’文件或形如‘core.数字’的文件比如‘core.1234’ 使用命令 gdb 运行程序名 core或core.数字 进入gdb然后使用bt命令 可以查看进程意外退出前函数调用的堆栈，内容为从上到下列出对应从里层到外层的函数调用历史。 如果进程意外退出不产生core文件，参考“ulimit -c core文件最大块大小”命令