--- crash-4.0-2.21/ppc64.c.orig	2006-03-08 10:59:13.000000000 -0800
+++ crash-4.0-2.21/ppc64.c	2006-03-05 13:49:52.000000000 -0800
@@ -1184,8 +1184,12 @@ ppc64_back_trace(struct gnu_request *req
 				ms->hwstacksize + STACK_FRAME_OVERHEAD;
 			bt->stackbuf = ms->hwstackbuf;
 			alter_stackbuf(bt);
-		} else 
-			error(FATAL, "cannot find the stack info");
+		} else {
+			if (CRASHDEBUG(1)) {
+				fprintf(fp, "cannot find the stack info.\n");
+			}
+			return;
+		}
 	}
 	
 		
@@ -1493,9 +1497,19 @@ ppc64_kdump_stack_frame(struct bt_info *
 		return FALSE;
 	}
 	*ksp = pt_regs->gpr[1];
-	readmem(*ksp+16, KVADDR, &unip, sizeof(ulong), "Regs NIP value",
-		FAULT_ON_ERROR);
-	*nip = unip;
+	if (IS_KVADDR(*ksp)) {
+		readmem(*ksp+16, KVADDR, &unip, sizeof(ulong), "Regs NIP value",
+			FAULT_ON_ERROR);
+		*nip = unip;
+	} else {
+		if (IN_TASK_VMA(bt_in->task, *ksp))
+			fprintf(fp, "%0lx: Task is running in user space\n",
+				bt_in->task);
+		else 
+			fprintf(fp, "%0lx: Invalid Stack Pointer %0lx\n",
+				bt_in->task, *ksp);
+		*nip = pt_regs->nip;
+	}
 
 	if (bt_in->flags && 
 	((BT_TEXT_SYMBOLS|BT_TEXT_SYMBOLS_PRINT|BT_TEXT_SYMBOLS_NOPRINT))) 
@@ -1505,7 +1519,9 @@ ppc64_kdump_stack_frame(struct bt_info *
 	 * Print the collected regs for the active task
 	 */
 	ppc64_print_regs(pt_regs);
-
+	if (!IS_KVADDR(*ksp)) 
+		return FALSE;
+	
 	fprintf(fp, " NIP [%016lx] %s\n", pt_regs->nip,
 		closest_symbol(pt_regs->nip));
 	if (unip != pt_regs->link)
@@ -1538,7 +1554,7 @@ ppc64_get_dumpfile_stack_frame(struct bt
 	/* 
 	 * For the kdump vmcore, Use SP and IP values that are saved in ptregs.
 	 */ 
-	if (pc->flags && KDUMP)
+	if (pc->flags & KDUMP)
 		return ppc64_kdump_stack_frame(bt_in, nip, ksp);
 
         bt = &bt_local;
@@ -2282,21 +2298,22 @@ parse_cmdline_arg(void)
 static void
 ppc64_paca_init(void)
 {
+#define BITS_FOR_LONG sizeof(ulong)*8
 	int i, cpus, nr_paca;
 	char *cpu_paca_buf;
 	ulong data_offset;
-	ulong per_cpu_offset;
-	ulong cpuid_offset;
-	signed short cpuid;
+	ulong cpu_online_map[NR_CPUS/BITS_FOR_LONG];
 
-	if (!symbol_exists("paca"))
+	if (!symbol_exists("paca") || !symbol_exists("cpu_online_map"))
 		return;
 
 	if (!MEMBER_EXISTS("paca_struct", "data_offset"))
 		return;
 	
+	readmem(symbol_value("cpu_online_map"), KVADDR, &cpu_online_map[0],
+		NR_CPUS/8, "cpu_online_map", FAULT_ON_ERROR);
+
 	STRUCT_SIZE_INIT(ppc64_paca, "paca_struct");
-	cpuid_offset = MEMBER_OFFSET("paca_struct", "hw_cpu_id");
 	data_offset = MEMBER_OFFSET("paca_struct", "data_offset");
 
 	cpu_paca_buf = GETBUF(SIZE(ppc64_paca));
@@ -2305,16 +2322,18 @@ ppc64_paca_init(void)
 		nr_paca = NR_CPUS;
 
 	for (i = cpus = 0; i < nr_paca; i++) {
+		div_t val = div(i, BITS_FOR_LONG);
+		/*
+		 * CPU online?
+		 */
+		if (!(cpu_online_map[val.quot] & (0x1UL << val.rem)))
+			continue;
+
         	readmem(symbol_value("paca") + (i * SIZE(ppc64_paca)),
              		KVADDR, cpu_paca_buf, SIZE(ppc64_paca),
 			"paca entry", FAULT_ON_ERROR);
 
-		cpuid = SHORT(cpu_paca_buf + cpuid_offset);
-		if (cpuid == -1)
-			continue;
-
-		per_cpu_offset = ULONG(cpu_paca_buf + data_offset); 
-		kt->__per_cpu_offset[i] = per_cpu_offset;
+		kt->__per_cpu_offset[i] = ULONG(cpu_paca_buf + data_offset);
 		kt->flags |= PER_CPU_OFF;
 		cpus++;
 	}