vmx guest debug?

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Aftersuccessfully launching a guest, the code does not stop in my guest entry function at "INT 3", function that I supplied into the GUEST RIP field of the VMCS. Does anyone have an idea why this is happening?

Here is a VMCS dump on my Intel Core2 CPU 6300 @1.86Ghz with Windows 7 x64:

(Some of the fields here are not supported by the processor, although i've printed them out as well.

The guest shares resources with the host for now. )

*** Host State ***

HOST_CR0: 0x80050031

HOST_CR3: 0x187000

HOST_CR4: 0x26f8

HOST_RSP: 0xfffffa800420ef50

HOST_RIP: 0xfffff8800485e749

HOST_CS_SELECTOR: 0x10

HOST_DS_SELECTOR: 0x28

HOST_SS_SELECTOR: 0x18

HOST_ES_SELECTOR: 0x28

HOST_FS_SELECTOR: 0x50

HOST_GS_SELECTOR: 0x28

HOST_TR_SELECTOR: 0x40

HOST_FS_BASE: 0xfffffffffffdf000

HOST_GS_BASE: 0x0

HOST_TR_BASE: 0xb96080

HOST_GDTR_BASE: 0xfffff80000b95000

HOST_IDTR_BASE: 0xfffff80000b95080

HOST_SYSENTER_CS: 0x0

HOST_SYSENTER_ESP: 0x0

HOST_SYSENTER_EIP: 0x0

HOST_PERF_GLOBAL_CTRL: 0xfffff88002322b78 // not supported

HOST_PAT: 0xfffff88002322b78// not supported

HOST_EFER: 0xfffff88002322b78// not supported

*** Guest Register State ***

GUEST_CR0: 0x80050031

GUEST_CR3: 0x187000

GUEST_CR4: 0x26f8

GUEST_RSP: 0xfffff88002322b90

GUEST_RIP: 0xfffff8800485e734

GUEST_DR7: 0x400

GUEST_RFLAGS 0x246

GUEST_CS_SELECTOR: 0x10

GUEST_DS_SELECTOR: 0x2b

GUEST_SS_SELECTOR: 0x18

GUEST_ES_SELECTOR: 0x2b

GUEST_FS_SELECTOR: 0x53

GUEST_GS_SELECTOR: 0x2b

GUEST_LDTR_SELECTOR: 0x0

GUEST_TR_SELECTOR: 0x40

GUEST_CS_BASE: 0x0

GUEST_DS_BASE: 0x0

GUEST_SS_BASE: 0x0

GUEST_ES_BASE: 0x0

GUEST_FS_BASE: 0xfffffffffffdf000

GUEST_GS_BASE: 0x0

GUEST_GDTR_BASE: 0xfffff80000b95000

GUEST_LDTR_BASE: 0x0

GUEST_IDTR_BASE: 0xfffff80000b95080

GUEST_TR_BASE: 0xb96080

GUEST_CS_LIMIT: 0x0

GUEST_DS_LIMIT: 0xffffffff

GUEST_SS_LIMIT: 0xffffffff

GUEST_ES_LIMIT: 0xffffffff

GUEST_FS_LIMIT: 0x3c00

GUEST_GS_LIMIT: 0xffffffff

GUEST_GDTR_LIMIT: 0x7f

GUEST_LDTR_LIMIT: 0x0

GUEST_IDTR_LIMIT: 0xfff

GUEST_TR_LIMIT: 0x67

GUEST_CS_AR_BYTES: 0x209b

GUEST_DS_AR_BYTES: 0xcff3

GUEST_SS_AR_BYTES: 0xcf93

GUEST_ES_AR_BYTES: 0xcff3

GUEST_FS_AR_BYTES: 0x40f3

GUEST_GS_AR_BYTES: 0xcff3

GUEST_LDTR_AR_BYTES: 0x10000

GUEST_TR_AR_BYTES: 0x8b

GUEST_IA32_DEBUGCTL: 0x0

GUEST_SYSENTER_CS: 0x0

GUEST_SYSENTER_ESP: 0x0

GUEST_SYSENTER_EIP: 0x0

GUEST_PERF_GLOBAL_CTRL: 0xfffff88002322b78// not supported

GUEST_PAT: 0xfffff88002322b78// not supported

GUEST_EFER: 0xfffff88002322b78// not supported

GUEST_SMBASE: 0x0

*** Guest Non-Register State ***

GUEST_ACTIVITY_STATE: 0x0

GUEST_INTERRUPTIBILITY_INFO: 0x0

GUEST_PENDING_DBG_EXCEPTIONS: 0x0

VMCS_LINK_POINTER: 0xffffffff

VMX_PREEMPTION_TIMER_VALUE: 0x2322b78

GUEST_PDPTR0: 0xfffff88002322b78

GUEST_PDPTR1: 0xfffff88002322b78

GUEST_PDPTR2: 0xfffff88002322b78

GUEST_PDPTR3: 0xfffff88002322b78

*** VM-EXECUTION CONTROL FIELDS ***

CPU_BASED_VM_EXEC_CONTROL: 0x401e172

SECONDARY_VM_EXEC_CONTROL: 0x2322b78

* Exception Bitmap *

EXCEPTION_BITMAP: 0xffffffff

PAGE_FAULT_ERROR_CODE_MASK: 0x0

PAGE_FAULT_ERROR_CODE_MATCH: 0x0

* I/O-Bitmap Addresses *

IO_BITMAP_A: 0x0

IO_BITMAP_B: 0x0

* Time-Stamp Counter Offset *

TSC_OFFSET: 0x0

* Guest/Host Masks and Read Shadows for CR0 and CR4 *

CR0_GUEST_HOST_MASK: 0x0

CR4_GUEST_HOST_MASK: 0x0

CR0_READ_SHADOW: 0x0

CR4_READ_SHADOW: 0x0

* CR3-Target Controls *

CR3_TARGET_VALUE0: 0x0

CR3_TARGET_VALUE1: 0x0

CR3_TARGET_VALUE2: 0x0

CR3_TARGET_VALUE3: 0x0

CR3_TARGET_COUNT: 0x0

* Controls for APIC Accesses *

APIC_ACCESS_ADDR: 0xfffff88002322b78

VIRTUAL_APIC_PAGE_ADDR: 0x0

TPR_THRESHOLD: 0x0

* MSR-Bitmap Address *

MSR_BITMAP: 0x0

* Extended-Page-Table Pointer *

EPT_POINTER: 0xfffff88002322b78

* Virtual-Processor Identifier (VPID) *

VIRTUAL_PROCESSOR_ID: 0x2322b78

* Controls for PAUSE-Loop Exiting *

PLE_GAP: 0x2322b78

PLE_WINDOW: 0x2322b78

*** VM-Exit Controls ***

VM_EXIT_CONTROLS: 0x36fff

VM_EXIT_MSR_STORE_COUNT: 0x0

VM_EXIT_MSR_STORE_ADDR: 0x0

VM_EXIT_MSR_LOAD_COUNT: 0x0

VM_EXIT_MSR_LOAD_ADDR: 0x0

*** VM-Entry Controls ***

VM_ENTRY_CONTROLS: 0x13ff

VM_ENTRY_MSR_LOAD_COUNT: 0x0

VM_ENTRY_MSR_LOAD_ADDR: 0x0

VM_ENTRY_INTR_INFO: 0x0

VM_ENTRY_EXCEPTION_ERROR_CODE: 0x0

VM_ENTRY_INSTRUCTION_LEN: 0x0

*** VM-Exit Information ***

VM_EXIT_REASON: 0x0

EXIT_QUALIFICATION: 0x0

GUEST_LINEAR_ADDRESS: 0x0

GUEST_PHYSICAL_ADDRESS: 0xfffff88002322b78

* Information for VM-Exits Due to Vectored Events *

VM_EXIT_INTR_INFO: 0x0

VM_EXIT_INTR_ERROR_CODE: 0x0

* Information for VM-Exits That Occur During Event Delivery *

IDT_VECTORING_INFO: 0x0

IDT_VECTORING_ERROR_CODE: 0x0

* Information for VM-Exits Due to Instruction Execution *

VM_EXIT_INSTRUCTION_LEN: 0x0

VMX_INSTRUCTION_INFO: 0x0

IO_RCX: 0x0

IO_RSI: 0x0

IO_RDI: 0x0

IO_RIP: 0x0

* VM-Instruction Error Field *

VM_INSTRUCTION_ERROR: 0xc

***************************************************

Thankyou.

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Learn to play the piano: www.scs.ubbcluj.ro/~tjie0910

[David_O_Intel1]

Ijust received a brief comment from an engineer as follows:

"The userneeds to identify whether the guestVM exits to the hypervisor due to int 3. Maybe they can try to use the monitor trap flag.It is enabled for Xen, but few people seem to use it."

An earlier comment from the same person:

"I noticed the guest exception map is 0xffffffff whichmeans that the userwants the guest VM toexit to the hypervisor on all kinds of exceptions. Hence, theywill get more VM exits than perhaps theyexpect. I understand they are looking for "int 3" VM exits."

David Ott