xref: /haiku/src/system/kernel/arch/m68k/arch_debug.cpp (revision 959ff00ddee8411dabb09211f3bfbd52d87229da)
1 /*
2  * Copyright 2003-2008, Haiku Inc. All rights reserved.
3  * Distributed under the terms of the MIT License.
4  *
5  * Authors:
6  * 		Axel Dörfler <axeld@pinc-software.de>
7  * 		Ingo Weinhold <bonefish@cs.tu-berlin.de>
8  * 		François Revol <revol@free.fr>
9  */
10 
11 
12 #include <arch/debug.h>
13 
14 #include <arch_cpu.h>
15 #include <debug.h>
16 #include <elf.h>
17 #include <kernel.h>
18 #include <kimage.h>
19 #include <thread.h>
20 
21 
22 struct stack_frame {
23 	struct stack_frame	*previous;
24 	addr_t				return_address;
25 };
26 
27 #define NUM_PREVIOUS_LOCATIONS 32
28 
29 extern struct iframe_stack gBootFrameStack;
30 
31 
32 static bool
33 already_visited(uint32 *visited, int32 *_last, int32 *_num, uint32 framePointer)
34 {
35 	int32 last = *_last;
36 	int32 num = *_num;
37 	int32 i;
38 
39 	for (i = 0; i < num; i++) {
40 		if (visited[(NUM_PREVIOUS_LOCATIONS + last - i)
41 				% NUM_PREVIOUS_LOCATIONS] == framePointer) {
42 			return true;
43 		}
44 	}
45 
46 	*_last = last = (last + 1) % NUM_PREVIOUS_LOCATIONS;
47 	visited[last] = framePointer;
48 
49 	if (num < NUM_PREVIOUS_LOCATIONS)
50 		*_num = num + 1;
51 
52 	return false;
53 }
54 
55 
56 static inline stack_frame *
57 get_current_stack_frame()
58 {
59 	stack_frame *frame;
60 	asm volatile("move.l %%fp,%0" : "=r"(frame));
61 	return frame;
62 }
63 
64 
65 static status_t
66 get_next_frame(addr_t framePointer, addr_t *next, addr_t *ip)
67 {
68 	struct thread *thread = thread_get_current_thread();
69 	addr_t oldFaultHandler = thread->fault_handler;
70 
71 	// set fault handler, so that we can safely access user stacks
72 	if (thread) {
73 		if (m68k_set_fault_handler(&thread->fault_handler, (addr_t)&&error))
74 			goto error;
75 	}
76 
77 	*ip = ((struct stack_frame *)framePointer)->return_address;
78 	*next = (addr_t)((struct stack_frame *)framePointer)->previous;
79 
80 	if (thread)
81 		thread->fault_handler = oldFaultHandler;
82 	return B_OK;
83 
84 error:
85 	thread->fault_handler = oldFaultHandler;
86 	return B_BAD_ADDRESS;
87 }
88 
89 
90 static void
91 print_stack_frame(struct thread *thread, addr_t ip, addr_t framePointer,
92 	addr_t nextFramePointer)
93 {
94 	addr_t diff = nextFramePointer - framePointer;
95 
96 	// kernel space/user space switch
97 	if (diff & 0x80000000)
98 		diff = 0;
99 
100 	// lookup symbol
101 	const char *symbol, *image;
102 	addr_t baseAddress;
103 	bool exactMatch;
104 	status_t status = elf_debug_lookup_symbol_address(ip, &baseAddress, &symbol,
105 		&image, &exactMatch);
106 	if (status != B_OK && !IS_KERNEL_ADDRESS(ip) && thread) {
107 		// try to locate the image in the images loaded into user space
108 		status = image_debug_lookup_user_symbol_address(thread->team, ip,
109 			&baseAddress, &symbol, &image, &exactMatch);
110 	}
111 	if (status == B_OK) {
112 		if (symbol != NULL) {
113 			kprintf("%08lx (+%4ld) %08lx   <%s>:%s + 0x%04lx%s\n", framePointer,
114 				diff, ip, image, symbol, ip - baseAddress,
115 				(exactMatch ? "" : " (nearest)"));
116 		} else {
117 			kprintf("%08lx (+%4ld) %08lx   <%s@%p>:unknown + 0x%04lx\n",
118 				framePointer, diff, ip, image, (void *)baseAddress,
119 				ip - baseAddress);
120 		}
121 	} else
122 		kprintf("%08lx (+%4ld) %08lx\n", framePointer, diff, ip);
123 }
124 
125 
126 static int
127 stack_trace(int argc, char **argv)
128 {
129 	uint32 previousLocations[NUM_PREVIOUS_LOCATIONS];
130 	struct iframe_stack *frameStack;
131 	struct thread *thread;
132 	addr_t framePointer;
133 	int32 i, num = 0, last = 0;
134 
135 	if (argc < 2) {
136 		thread = thread_get_current_thread();
137 		framePointer = (addr_t)get_current_stack_frame();
138 	} else {
139 // TODO: Add support for stack traces of other threads.
140 /*		thread_id id = strtoul(argv[1], NULL, 0);
141 		thread = thread_get_thread_struct_locked(id);
142 		if (thread == NULL) {
143 			kprintf("could not find thread %ld\n", id);
144 			return 0;
145 		}
146 
147 		// read %ebp from the thread's stack stored by a pushad
148 		ebp = thread->arch_info.current_stack.esp[2];
149 
150 		if (id != thread_get_current_thread_id()) {
151 			// switch to the page directory of the new thread to be
152 			// able to follow the stack trace into userland
153 			addr_t newPageDirectory = (addr_t)x86_next_page_directory(
154 				thread_get_current_thread(), thread);
155 
156 			if (newPageDirectory != 0) {
157 				read_cr3(oldPageDirectory);
158 				write_cr3(newPageDirectory);
159 			}
160 		}
161 */
162 kprintf("Stack traces of other threads not supported yet!\n");
163 return 0;
164 	}
165 
166 	// We don't have a thread pointer early in the boot process
167 	if (thread != NULL)
168 		frameStack = &thread->arch_info.iframes;
169 	else
170 		frameStack = &gBootFrameStack;
171 
172 	for (i = 0; i < frameStack->index; i++) {
173 		kprintf("iframe %p (end = %p)\n",
174 			frameStack->frames[i], frameStack->frames[i] + 1);
175 	}
176 
177 	if (thread != NULL) {
178 		kprintf("stack trace for thread 0x%lx \"%s\"\n", thread->id,
179 			thread->name);
180 
181 		kprintf("    kernel stack: %p to %p\n",
182 			(void *)thread->kernel_stack_base,
183 			(void *)(thread->kernel_stack_top));
184 		if (thread->user_stack_base != 0) {
185 			kprintf("      user stack: %p to %p\n",
186 				(void *)thread->user_stack_base,
187 				(void *)(thread->user_stack_base + thread->user_stack_size));
188 		}
189 	}
190 
191 	kprintf("frame            caller     <image>:function + offset\n");
192 
193 	for (;;) {
194 		// see if the frame pointer matches the iframe
195 		struct iframe *frame = NULL;
196 		for (i = 0; i < frameStack->index; i++) {
197 			if (framePointer == (((addr_t)frameStack->frames[i] - 8) & ~0xf)) {
198 				// it's an iframe
199 				frame = frameStack->frames[i];
200 				break;
201 			}
202 		}
203 
204 		if (frame) {
205 			kprintf("iframe at %p\n", frame);
206 			kprintf("   d0 0x%08lx    d1 0x%08lx    d2 0x%08lx    d3 0x%08lx\n",
207 				frame->d[0], frame->d[1], frame->d[2], frame->d[3]);
208 			kprintf("   d4 0x%08lx    d5 0x%08lx    d6 0x%08lx    d7 0x%08lx\n",
209 				frame->d[4], frame->d[5], frame->d[6], frame->d[7]);
210 			kprintf("   a0 0x%08lx    a1 0x%08lx    a2 0x%08lx    a3 0x%08lx\n",
211 				frame->a[0], frame->a[1], frame->a[2], frame->a[3]);
212 			kprintf("   a4 0x%08lx    a5 0x%08lx    a6 0x%08lx    a7 0x%08lx (sp)\n",
213 #warning M68K: a7 in iframe ??
214 				frame->a[4], frame->a[5], frame->a[6], -1L/*frame->a[7]*/);
215 
216 			/*kprintf("   pc 0x%08lx   ccr 0x%02x\n",
217 			  frame->pc, frame->ccr);*/
218 			kprintf("   pc 0x%08lx        sr 0x%04x\n",
219 				frame->cpu.pc, frame->cpu.sr);
220 #warning M68K: missing regs
221 
222 			print_stack_frame(thread, frame->cpu.pc, framePointer, frame->a[6]);
223  			framePointer = frame->a[6];
224 		} else {
225 			addr_t ip, nextFramePointer;
226 
227 			if (get_next_frame(framePointer, &nextFramePointer, &ip) != B_OK) {
228 				kprintf("%08lx -- read fault\n", framePointer);
229 				break;
230 			}
231 
232 			if (ip == 0 || framePointer == 0)
233 				break;
234 
235 			print_stack_frame(thread, ip, framePointer, nextFramePointer);
236 			framePointer = nextFramePointer;
237 		}
238 
239 		if (already_visited(previousLocations, &last, &num, framePointer)) {
240 			kprintf("circular stack frame: %p!\n", (void *)framePointer);
241 			break;
242 		}
243 		if (framePointer == 0)
244 			break;
245 	}
246 
247 /*	if (oldPageDirectory != 0) {
248 		// switch back to the previous page directory to no cause any troubles
249 		write_cr3(oldPageDirectory);
250 	}
251 */
252 
253 	return 0;
254 }
255 
256 
257 
258 // #pragma mark -
259 
260 
261 void
262 arch_debug_save_registers(int *regs)
263 {
264 }
265 
266 
267 bool
268 arch_debug_contains_call(struct thread *thread, const char *symbol,
269 	addr_t start, addr_t end)
270 {
271 	return false;
272 }
273 
274 
275 void *
276 arch_debug_get_caller(void)
277 {
278 	// TODO: implement me
279 	//return __builtin_frame_address(1);
280 	struct stack_frame *frame;
281 	//frame = __builtin_frame_address(0);
282 	frame = get_current_stack_frame();
283 	return (void *)frame->previous->return_address;
284 }
285 
286 
287 int32
288 arch_debug_get_stack_trace(addr_t* returnAddresses, int32 maxCount,
289 	int32 skipFrames, bool userOnly)
290 {
291 	struct iframe_stack *frameStack;
292 	addr_t framePointer;
293 	int32 count = 0;
294 	int32 i, num = 0, last = 0;
295 
296 	// always skip our own frame
297 	skipFrames++;
298 
299 	struct thread* thread = thread_get_current_thread();
300 	framePointer = (addr_t)get_current_stack_frame();
301 
302 	// We don't have a thread pointer early in the boot process
303 	if (thread != NULL)
304 		frameStack = &thread->arch_info.iframes;
305 	else
306 		frameStack = &gBootFrameStack;
307 
308 	while (framePointer != 0 && count < maxCount) {
309 		// see if the frame pointer matches the iframe
310 		struct iframe *frame = NULL;
311 		for (i = 0; i < frameStack->index; i++) {
312 			if (framePointer == (((addr_t)frameStack->frames[i] - 8) & ~0xf)) {
313 				// it's an iframe
314 				frame = frameStack->frames[i];
315 				break;
316 			}
317 		}
318 
319 		addr_t ip;
320 		addr_t nextFrame;
321 
322 		if (frame) {
323 			ip = frame->cpu.pc;
324  			nextFrame = frame->a[6];
325 		} else {
326 			if (get_next_frame(framePointer, &nextFrame, &ip) != B_OK)
327 				break;
328 		}
329 
330 		if (skipFrames <= 0 && (!userOnly || IS_USER_ADDRESS(framePointer)))
331 			returnAddresses[count++] = ip;
332 		else
333 			skipFrames--;
334 
335 		framePointer = nextFrame;
336 	}
337 
338 	return count;
339 }
340 
341 
342 void*
343 arch_debug_get_interrupt_pc()
344 {
345 	// TODO: Implement!
346 	return NULL;
347 }
348 
349 
350 bool
351 arch_is_debug_variable_defined(const char* variableName)
352 {
353 	// TODO: Implement!
354 	return false;
355 }
356 
357 
358 status_t
359 arch_set_debug_variable(const char* variableName, uint64 value)
360 {
361 	// TODO: Implement!
362 	return B_ENTRY_NOT_FOUND;
363 }
364 
365 
366 status_t
367 arch_get_debug_variable(const char* variableName, uint64* value)
368 {
369 	// TODO: Implement!
370 	return B_ENTRY_NOT_FOUND;
371 }
372 
373 
374 status_t
375 arch_debug_init(kernel_args *args)
376 {
377 	add_debugger_command("where", &stack_trace, "Same as \"sc\"");
378 	add_debugger_command("bt", &stack_trace, "Same as \"sc\" (as in gdb)");
379 	add_debugger_command("sc", &stack_trace, "Stack crawl for current thread");
380 
381 	return B_NO_ERROR;
382 }
383 
384