xref: /openbsd/sys/arch/powerpc/ddb/db_trace.c (revision 274d7c50)
1 /*	$OpenBSD: db_trace.c,v 1.14 2019/11/07 16:08:08 mpi Exp $	*/
2 /*	$NetBSD: db_trace.c,v 1.15 1996/02/22 23:23:41 gwr Exp $	*/
3 
4 /*
5  * Mach Operating System
6  * Copyright (c) 1992 Carnegie Mellon University
7  * All Rights Reserved.
8  *
9  * Permission to use, copy, modify and distribute this software and its
10  * documentation is hereby granted, provided that both the copyright
11  * notice and this permission notice appear in all copies of the
12  * software, derivative works or modified versions, and any portions
13  * thereof, and that both notices appear in supporting documentation.
14  *
15  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
17  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18  *
19  * Carnegie Mellon requests users of this software to return to
20  *
21  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
22  *  School of Computer Science
23  *  Carnegie Mellon University
24  *  Pittsburgh PA 15213-3890
25  *
26  * any improvements or extensions that they make and grant Carnegie Mellon
27  * the rights to redistribute these changes.
28  */
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/proc.h>
33 #include <sys/user.h>
34 
35 #include <uvm/uvm_extern.h>
36 
37 #include <machine/db_machdep.h>
38 #include <machine/signal.h>
39 #include <machine/pcb.h>
40 #include <machine/pmap.h>
41 
42 #include <ddb/db_access.h>
43 #include <ddb/db_sym.h>
44 #include <ddb/db_variables.h>
45 #include <ddb/db_interface.h>
46 #include <ddb/db_output.h>
47 
48 db_regs_t ddb_regs;
49 
50 struct db_variable db_regs[] = {
51 	{ "r0",  (long *)&ddb_regs.fixreg[0],	FCN_NULL },
52 	{ "r1",  (long *)&ddb_regs.fixreg[1],	FCN_NULL },
53 	{ "r2",  (long *)&ddb_regs.fixreg[2],	FCN_NULL },
54 	{ "r3",  (long *)&ddb_regs.fixreg[3],	FCN_NULL },
55 	{ "r4",  (long *)&ddb_regs.fixreg[4],	FCN_NULL },
56 	{ "r5",  (long *)&ddb_regs.fixreg[5],	FCN_NULL },
57 	{ "r6",  (long *)&ddb_regs.fixreg[6],	FCN_NULL },
58 	{ "r7",  (long *)&ddb_regs.fixreg[7],	FCN_NULL },
59 	{ "r8",  (long *)&ddb_regs.fixreg[8],	FCN_NULL },
60 	{ "r9",  (long *)&ddb_regs.fixreg[9],	FCN_NULL },
61 	{ "r10", (long *)&ddb_regs.fixreg[10],	FCN_NULL },
62 	{ "r11", (long *)&ddb_regs.fixreg[11],	FCN_NULL },
63 	{ "r12", (long *)&ddb_regs.fixreg[12],	FCN_NULL },
64 	{ "r13", (long *)&ddb_regs.fixreg[13],	FCN_NULL },
65 	{ "r14", (long *)&ddb_regs.fixreg[13],	FCN_NULL },
66 	{ "r15", (long *)&ddb_regs.fixreg[13],	FCN_NULL },
67 	{ "r16", (long *)&ddb_regs.fixreg[13],	FCN_NULL },
68 	{ "r17", (long *)&ddb_regs.fixreg[17],	FCN_NULL },
69 	{ "r18", (long *)&ddb_regs.fixreg[18],	FCN_NULL },
70 	{ "r19", (long *)&ddb_regs.fixreg[19],	FCN_NULL },
71 	{ "r20", (long *)&ddb_regs.fixreg[20],	FCN_NULL },
72 	{ "r21", (long *)&ddb_regs.fixreg[21],	FCN_NULL },
73 	{ "r22", (long *)&ddb_regs.fixreg[22],	FCN_NULL },
74 	{ "r23", (long *)&ddb_regs.fixreg[23],	FCN_NULL },
75 	{ "r24", (long *)&ddb_regs.fixreg[24],	FCN_NULL },
76 	{ "r25", (long *)&ddb_regs.fixreg[25],	FCN_NULL },
77 	{ "r26", (long *)&ddb_regs.fixreg[26],	FCN_NULL },
78 	{ "r27", (long *)&ddb_regs.fixreg[27],	FCN_NULL },
79 	{ "r28", (long *)&ddb_regs.fixreg[28],	FCN_NULL },
80 	{ "r29", (long *)&ddb_regs.fixreg[29],	FCN_NULL },
81 	{ "r30", (long *)&ddb_regs.fixreg[30],	FCN_NULL },
82 	{ "r31", (long *)&ddb_regs.fixreg[31],	FCN_NULL },
83 	{ "lr",  (long *)&ddb_regs.lr,		FCN_NULL },
84 	{ "cr",  (long *)&ddb_regs.cr,		FCN_NULL },
85 	{ "xer", (long *)&ddb_regs.xer,		FCN_NULL },
86 	{ "ctr", (long *)&ddb_regs.ctr,		FCN_NULL },
87 	{ "iar", (long *)&ddb_regs.srr0,		FCN_NULL },
88 	{ "msr", (long *)&ddb_regs.srr1,		FCN_NULL },
89 };
90 
91 struct db_variable *db_eregs = db_regs + nitems(db_regs);
92 
93 /*
94  * this is probably hackery.
95  */
96 void
97 db_save_regs(struct trapframe *frame)
98 {
99 	bcopy(frame, &ddb_regs, sizeof (struct trapframe));
100 }
101 
102 /* from locore.S */
103 extern vaddr_t trapexit;
104 extern vaddr_t esym;
105 #define	INTSTK		(8*1024)	/* 8K interrupt stack */
106 
107 #define	INKERNEL(va)	(((vaddr_t)(va)) >= VM_MIN_KERNEL_ADDRESS &&	\
108 			((vaddr_t)(va)) < VM_MAX_KERNEL_ADDRESS)
109 
110 #define	ININTSTK(va)	(((vaddr_t)(va)) >= round_page(esym) &&		\
111 			((vaddr_t)(va)) < (round_page(esym) + INTSTK))
112 
113 /*
114  *	Frame tracing.
115  */
116 void
117 db_stack_trace_print(db_expr_t addr, int have_addr, db_expr_t count,
118     char *modif, int (*pr)(const char *, ...))
119 {
120 	vaddr_t		 lr, sp, lastsp, *db_fp_args;
121 	db_expr_t	 offset;
122 	Elf_Sym		*sym;
123 	char		*name;
124 	char		 c, *cp = modif;
125 	int		 i, narg, trace_proc = 0;
126 
127 	while ((c = *cp++) != 0) {
128 		if (c == 'p')
129 			trace_proc = 1;
130 	}
131 
132 	if (!have_addr) {
133 		sp = ddb_regs.fixreg[1];
134 		lr = ddb_regs.srr0;
135 	} else {
136 		if (trace_proc) {
137 			struct proc *p = tfind((pid_t)addr);
138 			if (p == NULL) {
139 				(*pr) ("not found\n");
140 				return;
141 			}
142 			addr = p->p_addr->u_pcb.pcb_sp;
143 		}
144 		sp = addr;
145 		db_read_bytes(sp + 4, sizeof(vaddr_t), (char *)&lr);
146 	}
147 
148 	while (count && sp != 0) {
149 		/*
150 		 * lr contains the return address, so adjust its value
151 		 * to display the offset of the calling address.
152 		 */
153 		sym = db_search_symbol(lr - 4, DB_STGY_ANY, &offset);
154 		db_symbol_values(sym, &name, NULL);
155 
156 		if (name == NULL || strcmp(name, "end") == 0) {
157 			(*pr)("at 0x%lx", lr - 4);
158 		} else {
159 			narg = db_ctf_func_numargs(sym);
160 			if (narg < 0 || narg > 8)
161 				narg = 8;
162 
163 			(*pr)("%s(", name);
164 
165 			if (narg > 0) {
166 				db_fp_args = (vaddr_t *)(sp + 8);
167 
168 				for (i = 0; i < narg; i++) {
169 					(*pr)("%lx", db_fp_args[i]);
170 					if (i != (narg-1))
171 						(*pr)(",");
172 				}
173 			}
174 
175 			(*pr)(") at ");
176 			db_printsym(lr - 4, DB_STGY_PROC, pr);
177 		}
178 		(*pr)("\n");
179 
180 		lastsp = sp;
181 
182 		/*
183 		 * Abuse the fact that the return address of the trap()
184 		 * function is always 'trapexit'.
185 		 */
186 		if (lr == (vaddr_t)&trapexit) {
187 			struct trapframe *tf = (struct trapframe *)(sp + 8);
188 			uint32_t code = tf->fixreg[0];
189 			uint32_t type = tf->exc;
190 
191 			if (tf->srr1 & PSL_PR)
192 				type |= EXC_USER;
193 
194 			if (type == (EXC_SC|EXC_USER))
195 				(*pr)("--- syscall (number %d) ---\n", code);
196 			else
197 				(*pr)("--- trap (type 0x%x) ---\n", type);
198 		}
199 
200 		db_read_bytes(sp, sizeof(vaddr_t), (char *)&sp);
201 		if (sp == 0)
202 			break;
203 
204 		db_read_bytes(sp + 4, sizeof(vaddr_t), (char *)&lr);
205 
206 		if (INKERNEL(sp)) {
207 			if (sp <= lastsp) {
208 				(*pr)("Bad frame pointer: 0x%lx\n", sp);
209 				break;
210 			}
211 
212 			if (ININTSTK(lastsp))
213 				(*pr)("--- interrupt ---\n");
214 
215 		} else  {
216 			if (!ININTSTK(sp)) {
217 				(*pr)("End of kernel: 0x%lx\n", sp);
218 				break;
219 			}
220 		}
221 		--count;
222 	}
223 	(*pr)("end trace frame: 0x%lx, count: %d\n", sp, count);
224 }
225