1/*	$OpenBSD: db_trace.c,v 1.16 2021/03/25 04:12:00 jsg Exp $	*/
2/*	$NetBSD: db_trace.c,v 1.8 2003/01/17 22:28:48 thorpej Exp $	*/
3
4/*
5 * Copyright (c) 2000, 2001 Ben Harris
6 * Copyright (c) 1996 Scott K. Stevens
7 *
8 * Mach Operating System
9 * Copyright (c) 1991,1990 Carnegie Mellon University
10 * All Rights Reserved.
11 *
12 * Permission to use, copy, modify and distribute this software and its
13 * documentation is hereby granted, provided that both the copyright
14 * notice and this permission notice appear in all copies of the
15 * software, derivative works or modified versions, and any portions
16 * thereof, and that both notices appear in supporting documentation.
17 *
18 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
19 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
20 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
21 *
22 * Carnegie Mellon requests users of this software to return to
23 *
24 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
25 *  School of Computer Science
26 *  Carnegie Mellon University
27 *  Pittsburgh PA 15213-3890
28 *
29 * any improvements or extensions that they make and grant Carnegie the
30 * rights to redistribute these changes.
31 */
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/proc.h>
36#include <sys/user.h>
37#include <machine/db_machdep.h>
38
39#include <ddb/db_interface.h>
40#include <ddb/db_sym.h>
41#include <ddb/db_output.h>
42
43db_regs_t ddb_regs;
44
45#define INKERNEL(va)	(((vaddr_t)(va)) >= VM_MIN_KERNEL_ADDRESS)
46
47/*
48 *          return link value       [fp, #+4]
49 *          return fp value         [fp]        <- fp points to here
50 */
51#define FR_RFP	(0)
52#define FR_RLV	(+1)
53
54void
55db_stack_trace_print(db_expr_t addr, int have_addr, db_expr_t count,
56    char *modif, int (*pr)(const char *, ...))
57{
58	u_int32_t	*frame, *lastframe;
59	char		c, *cp = modif;
60	int		kernel_only = 1;
61	int		trace_thread = 0;
62	vaddr_t		scp;
63
64	while ((c = *cp++) != 0) {
65		if (c == 'u')
66			kernel_only = 0;
67		if (c == 't')
68			trace_thread = 1;
69	}
70
71	if (!have_addr) {
72		frame = (u_int32_t *)(ddb_regs.tf_r11);
73		scp = ddb_regs.tf_pc;
74	} else {
75		if (trace_thread) {
76			struct proc *p;
77			struct user *u;
78			(*pr) ("trace: pid %d ", (int)addr);
79			p = tfind(addr);
80			if (p == NULL) {
81				(*pr)("not found\n");
82				return;
83			}
84			u = p->p_addr;
85			frame = (u_int32_t *)(u->u_pcb.pcb_un.un_32.pcb32_r11);
86			(*pr)("at %p\n", frame);
87			scp = u->u_pcb.pcb_un.un_32.pcb32_pc;
88		} else
89			frame = (u_int32_t *)(addr);
90	}
91	lastframe = NULL;
92
93	while (count-- && frame != NULL) {
94		db_printsym(scp, DB_STGY_PROC, pr);
95		(*pr)("\n\trlv=0x%08x rfp=0x%08x\n", frame[FR_RLV], frame[FR_RFP]);
96		scp = frame[FR_RLV];
97
98		/*
99		 * Switch to next frame up
100		 */
101		if (frame[FR_RFP] == 0)
102			break; /* Top of stack */
103
104		lastframe = frame;
105		frame = (u_int32_t *)(frame[FR_RFP]);
106
107		if (INKERNEL((int)frame)) {
108			/* staying in kernel */
109			if (frame <= lastframe) {
110				(*pr)("Bad frame pointer: %p\n", frame);
111				break;
112			}
113		} else if (INKERNEL((int)lastframe)) {
114			/* switch from user to kernel */
115			if (kernel_only)
116				break;	/* kernel stack only */
117		} else {
118			/* in user */
119			if (frame <= lastframe) {
120				(*pr)("Bad user frame pointer: %p\n",
121					  frame);
122				break;
123			}
124		}
125	}
126}
127