6 files changed, 48 insertions(+), 11 deletions(-)

M pc/dat.h
M pc/main.c
M pc/mem.h
M pc/trap.c
M port/chan.c
M port/devcons.c

@@ 195,3 195,4 @@ extern int	cpuflag;		/* true if this is a CPU */
 extern Mach	*m;
 extern Proc	*up;
 extern char	filaddr[];
+extern ulong	crasharea;

@@ 31,6 31,7 @@ char filaddr[NAMELEN];
 char *confname[MAXCONF];
 char *confval[MAXCONF];
 int nconf;
+ulong crasharea;
 
 /* memory map */
 #define MAXMEG 64


@@ 63,6 64,7 @@ main(void)
 	chandevreset();
 	swapinit();
 	userinit();
+conf.npage0 += CRASHSIZE;
 	schedinit();
 }
 


@@ 353,7 355,6 @@ confinit(void)
 			/*
 			 *  zero memory to set ECC but skip over the kernel
 			 *  do a quick memory test also
-			 */
 			if(i != 1){
 				for(j = 0; j < MB/BY2PG; j += BY2PG){
 					lp = mapaddr(KZERO|(i*MB+j));


@@ 376,6 377,7 @@ confinit(void)
 					memset(lp, 0, BY2PG);
 				}
 			}
+			 */
 		}
 		x += 0x3141526;
 	}


@@ 387,16 389,17 @@ confinit(void)
 	conf.base0 = ktop;
 	for(i = 1; mmap[i] == 'x'; i++)
 		;
-	conf.npage0 = (i*MB - ktop)/BY2PG;
+	conf.npage0 = (i*MB - ktop - CRASHSIZE)/BY2PG;
+	crasharea = KZERO|(conf.base0 + conf.npage0*BY2PG);
 	conf.topofmem = i*MB;
 
 	/*
-	 *  bank1 usually goes from the end of BOOTARGS to 640k
+	 *  bank1 usually goes from the end of BOOTARGS to 640k - crash space
 	 */
-	conf.base1 = (ulong)(BOOTARGS+BOOTARGSLEN);
+	conf.base1 = (ulong)(BOOTARGS + BOOTARGSLEN);
 	conf.base1 = PGROUND(conf.base1);
 	conf.base1 = PADDR(conf.base1);
-	conf.npage1 = (640*1024-conf.base1)/BY2PG;
+	conf.npage1 = (640*1024 - conf.base1)/BY2PG;
 
 	/*
 	 *  if there is a hole in memory (due to a shadow BIOS) make the


@@ 568,15 571,11 @@ procrestore(Proc *p)
 	USED(p);
 }
 
-
 /*
  *  the following functions all are slightly different from
  *  PC to PC.
  */
 
-/*
- *  reset the i387 chip
- */
 void
 exit(int ispanic)
 {

@@ 55,6 55,10 @@
 
 #define	MACHSIZE	4096
 
+/*
+ *  an area for storing crash info to be picked up later
+ */
+#define CRASHSIZE	(KSTACK+BY2PG)
 
 /*
  *  known 80386 segments (in GDT) and their selectors

@@ 61,6 61,19 @@ struct
 	int	free;
 } halloc;
 
+/*
+ *  somewhere to drop crash info
+ */
+typedef struct
+{
+	ulong	magic;
+	void	*kbot;
+	void	*ksp;
+	char	text[NAMELEN];
+	Ureg	ureg;
+	uchar	kstack[KSTACK];
+} Crashstate;
+
 void
 sethvec(int v, void (*r)(void), int type, int pri)
 {


@@ 340,12 353,20 @@ dumpregs2(Ureg *ur)
 void
 dumpregs(Ureg *ur)
 {
+	Crashstate *cs;
+	extern ulong etext;
 	ulong *x;
 
+
 	x = (ulong*)(ur+1);
 	dumpregs2(ur);
 	print("  magic %lux %lux %lux\n", x[0], x[1], x[2]);
 	print("  ur %lux up %lux\n", ur, up);
+
+	/* save crash info */
+	print("crasharea 0x%lux\n", crasharea);
+	cs = (Crashstate*)crasharea;
+	memmove(&cs->ureg, ur, sizeof(Ureg));
 }
 
 void


@@ 354,13 375,14 @@ dumpstack(void)
 	ulong l, v, i;
 	extern ulong etext;
 	int lim;
+	Crashstate *cs;
 
 	if(up == 0)
 		return;
 
 	i = 0;
 	lim = 6;
-	for(l=(ulong)&l; l<(ulong)(up->kstack+BY2PG) && lim; l+=4){
+	for(l=(ulong)&l; l<(ulong)(up->kstack+KSTACK) && lim; l+=4){
 		v = *(ulong*)l;
 		if(KTZERO < v && v < (ulong)&etext){
 			print("%lux ", v);


@@ 373,6 395,14 @@ dumpstack(void)
 		}
 	}
 
+	/* save crash info */
+	print("crasharea 0x%lux\n", crasharea);
+	cs = (Crashstate*)crasharea;
+	memmove(cs->kstack, up->kstack, KSTACK);
+	cs->kbot = up->kstack;
+	memmove(cs->text, up->text, NAMELEN);
+	cs->magic = 0xdeaddead;
+	cs->ksp = &l;
 }
 
 /*

@@ 130,7 130,7 @@ chanfree(Chan *c)
 void
 close(Chan *c)
 {
-	if(c == 0 || (c->flag&CFREE))
+	if(c->flag&CFREE)
 		panic("close");
 
 	if(decref(c))

@@ 214,6 214,9 @@ echo(Rune r, char *buf, int n)
 		switch(r){
 		case 0x14:
 			break;	/* pass it on */
+		case 's':
+			dumpstack();
+			break;
 		case 'x':
 			xsummary();
 			ixsummary();