halt failure

nachos 5.0j initializing... config interrupt timer processor console user-check grader


START: Lottery Scheduler Test A
OBJECTIVE: TEST Lottery Scheduler Starvation Prevention
Thread #1 is starting (time = 40)
Thread #0 is starting (time = 430)
Thread #1 is exiting (time = 10140)
Thread #0 is exiting (time = 20180)
Low Priority Thread Ran At Least Once: true
Low Priority Thread Run Percentage: 0.009900990099009901
Expected Percentage: ~0.01
END: Lottery Scheduler Test A


START: Lottery Scheduler Test B
OBJECTIVE: Test Lottery Scheduler Priority Donation
Thread #4 is attempting to acquire Lock (time = 20270)
Thread #4 has acquired Lock (time = 20280)
Thread #3 is starting (time = 20360)
Thread #2 is attempting to acquire Lock (time = 20370)
Thread #4 has released Lock (time = 35600)
Thread #4 is exiting (time = 35610)
Thread #2 has acquired Lock (time = 35650)
Thread #3 is exiting (time = 44810)
Thread #2 has released Lock (time = 50510)
Thread #2 is exiting (time = 50520)
Resource Holder Thread Percentage: 0.6544502617801047
Expected Percentage: ~0.66
END: Lottery Scheduler Test B
	UserKernel.run()
	UserProcess constructor
	physical page allocation succeeded at 0
		length of freepage: 63
	physical page allocation succeeded at 1
		length of freepage: 62
	physical page allocation succeeded at 2
		length of freepage: 61
	physical page allocation succeeded at 3
		length of freepage: 60
	physical page allocation succeeded at 4
		length of freepage: 59
	physical page allocation succeeded at 5
		length of freepage: 58
	physical page allocation succeeded at 6
		length of freepage: 57
	physical page allocation succeeded at 7
		length of freepage: 56
	validOwnedPages: 8
	initializing .text section (1 pages)
ID: 245	page # 0 free page available
	initializing .data section (0 pages)
	initializing .bss section (0 pages)
UserProcess.execute halt.coff
	ID: 245	UserProcess.restoreState; length 8
	ID: 245	UserProcess.restoreState; length 8

nachos.machine.AssertionFailureError: Unexpected exception
	at nachos.machine.Lib.assertTrue(Lib.java:89)
	at nachos.machine.Lib.assertNotReached(Lib.java:106)
	at nachos.userprog.UserProcess.handleException(UserProcess.java:872)
	at nachos.userprog.UserKernel.exceptionHandler(UserKernel.java:97)
	at nachos.userprog.UserKernel$1.run(UserKernel.java:41)
	at nachos.machine.Processor$MipsException.handle(Processor.java:603)
	at nachos.machine.Processor.run(Processor.java:101)
	at nachos.userprog.UThread.runProgram(UThread.java:31)
	at nachos.userprog.UThread.access$0(UThread.java:27)
	at nachos.userprog.UThread$1.run(UThread.java:20)
	at nachos.threads.KThread.runThread(KThread.java:162)
	at nachos.threads.KThread.access$1(KThread.java:160)
	at nachos.threads.KThread$1.run(KThread.java:151)
	at nachos.machine.TCB.threadroot(TCB.java:235)
	at nachos.machine.TCB.access$3(TCB.java:210)
	at nachos.machine.TCB$1.run(TCB.java:93)
	at java.lang.Thread.run(Thread.java:680)