[PATCH] Debugger extension: Add cr3 to debug/bp exception kvm_exit struct

[Peter Shier <pshier@xxxxxxxxxx>]

From: Ken Hofsass <hofsass@xxxxxxxxxx>

Enables determining whether a debug/break event is associated with a guest
process of interest.

Signed-off-by: Ken Hofsass <hofsass@xxxxxxxxxx>
Signed-off-by: Peter Shier <pshier@xxxxxxxxxx>
Reviewed-by: Jim Mattson <jmattson@xxxxxxxxxx>
---
 arch/x86/include/uapi/asm/kvm.h | 1 +
 arch/x86/kvm/vmx.c              | 2 ++
 arch/x86/kvm/x86.c              | 1 +
 include/uapi/linux/kvm.h        | 1 +
 4 files changed, 5 insertions(+)

diff --git a/arch/x86/include/uapi/asm/kvm.h b/arch/x86/include/uapi/asm/kvm.h
index c535c2fdea136..7aa39142a1b88 100644
--- a/arch/x86/include/uapi/asm/kvm.h
+++ b/arch/x86/include/uapi/asm/kvm.h
@@ -254,6 +254,7 @@ struct kvm_debug_exit_arch {
 	__u64 pc;
 	__u64 dr6;
 	__u64 dr7;
+	__u64 cr3;
 };
 
 #define KVM_GUESTDBG_USE_SW_BP		0x00010000
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 1689f433f3a08..a87ddef4c79bc 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6751,6 +6751,7 @@ static int handle_exception(struct kvm_vcpu *vcpu)
 		rip = kvm_rip_read(vcpu);
 		kvm_run->debug.arch.pc = vmcs_readl(GUEST_CS_BASE) + rip;
 		kvm_run->debug.arch.exception = ex_no;
+		kvm_run->debug.arch.cr3 = kvm_read_cr3(vcpu);
 		break;
 	default:
 		kvm_run->exit_reason = KVM_EXIT_EXCEPTION;
@@ -6969,6 +6970,7 @@ static int handle_dr(struct kvm_vcpu *vcpu)
 			vcpu->run->debug.arch.dr6 = vcpu->arch.dr6;
 			vcpu->run->debug.arch.dr7 = dr7;
 			vcpu->run->debug.arch.pc = kvm_get_linear_rip(vcpu);
+			vcpu->run->debug.arch.cr3 = kvm_read_cr3(vcpu);
 			vcpu->run->debug.arch.exception = DB_VECTOR;
 			vcpu->run->exit_reason = KVM_EXIT_DEBUG;
 			return 0;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 0046aa70205aa..dd4d1ae37b794 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2891,6 +2891,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
  	case KVM_CAP_SPLIT_IRQCHIP:
 	case KVM_CAP_IMMEDIATE_EXIT:
 	case KVM_CAP_GET_MSR_FEATURES:
+	case KVM_CAP_DEBUG_EVENT_PG_BASE_ADDR:
 		r = 1;
 		break;
 	case KVM_CAP_SYNC_REGS:
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index b6270a3b38e9f..1eab59739dcdc 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -949,6 +949,7 @@ struct kvm_ppc_resize_hpt {
 #define KVM_CAP_GET_MSR_FEATURES 153
 #define KVM_CAP_HYPERV_EVENTFD 154
 #define KVM_CAP_HYPERV_TLBFLUSH 155
+#define KVM_CAP_DEBUG_EVENT_PG_BASE_ADDR 156
 
 #ifdef KVM_CAP_IRQ_ROUTING
 
-- 
2.18.0.233.g985f88cf7e-goog