vmx(1): support debug instructions

sys/src/cmd/vmx/dat.h

@@ -15,6 +15,17 @@ enum {
 #define RBX "bx"
 #define RCX "cx"
 #define RDX "dx"
+#define RBP "bp"
+#define RSI "si"
+#define RDI "di"
+#define R8 "r8"
+#define R9 "r9"
+#define R10 "r10"
+#define R11 "r11"
+#define R12 "r12"
+#define R13 "r13"
+#define R14 "r14"
+#define R15 "r15"
 
 enum {
 	MMIORD = 0,
@@ -72,8 +83,12 @@ struct PCICap {
 };
 
 enum {
+	/* irqline argument */
 	IRQLTOGGLE = -1,
 	IRQLLOHI = -2,
+	
+	/* postexc */
+	NOERRC = -1,
 };
 
 typedef struct VgaMode VgaMode;

sys/src/cmd/vmx/exith.c

@@ -75,7 +75,7 @@ iohandler(ExitInfo *ei)
 	isin = (ei->qual & 8) != 0;
 	if((ei->qual & 1<<4) != 0){
 		vmerror("i/o string instruction not implemented");
-		postexc("#ud", 0);
+		postexc("#ud", NOERRC);
 		return;
 	}
 	if(isin){
@@ -320,6 +320,37 @@ rdwrmsr(ExitInfo *ei)
 	skipinstr(ei);
 }
 
+static void
+movdr(ExitInfo *ei)
+{
+	static char *reg[16] = {
+		RAX, RCX, RDX, RBX,
+		RSP, RBP, RSI, RDI,
+		R8, R9, R10, R11,
+		R12, R13, R14, R15
+	};
+	static char *dr[8] = { "dr0", "dr1", "dr2", "dr3", nil, nil, "dr6", "dr7" };
+	int q;
+	
+	q = ei->qual;
+	if((q & 6) == 4){
+		postexc("#gp", 0);
+		return;
+	}
+	if((q & 16) != 0)
+		rset(reg[q >> 8 & 15], rget(dr[q & 7]));
+	else
+		rset(dr[q & 7], rget(reg[q >> 8 & 15]));
+	skipinstr(ei);
+}
+
+static void
+dbgexc(ExitInfo *ei)
+{
+	rset("dr6", rget("dr6") | ei->qual);
+	postexc("#db", NOERRC);
+}
+
 static void
 hlt(ExitInfo *ei)
 {
@@ -347,6 +378,8 @@ static ExitType etypes[] = {
 	{"*ack", irqackhand},
 	{".rdmsr", rdwrmsr},
 	{".wrmsr", rdwrmsr},
+	{".movdr", movdr},
+	{"#db", dbgexc},
 };
 
 void
@@ -391,7 +424,7 @@ processexit(char *msg)
 		}
 	if(*f[0] == '.'){
 		vmerror("vmx: unknown instruction %s", f[0]+1);
-		postexc("#ud", 0);
+		postexc("#ud", NOERRC);
 		return;
 	}
 	if(*f[0] == '*'){

sys/src/cmd/vmx/fns.h

@@ -13,7 +13,7 @@ int ctl(char *, ...);
 void registermmio(uvlong, uvlong, uvlong (*)(int, uvlong, uvlong));
 void irqline(int, int);
 void irqack(int);
-void postexc(char *, u32int);
+void postexc(char *, vlong);
 void vgaresize(void);
 void uartinit(int, char *);
 void sendnotif(void (*)(void *), void *);

sys/src/cmd/vmx/vmx.c

@@ -318,10 +318,14 @@ mksegment(char *sn)
 }
 
 void
-postexc(char *name, u32int)
+postexc(char *name, vlong code)
 {
-	if(ctl("exc %s", name) < 0)
+	if(code >= 0){
-		sysfatal("ctl(postexc): %r");
+		if(ctl("exc %s,%#ux", name, (u32int)code) < 0)
+			sysfatal("ctl(postexc): %r");
+	}else
+		if(ctl("exc %s", name) < 0)
+			sysfatal("ctl(postexc): %r");
 }
 
 void