2 * Copyright (c) 2004 Marcel Moolenaar
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
30 #include <sys/param.h>
34 #include <machine/pcb.h>
35 #include <machine/frame.h>
36 #include <machine/segments.h>
37 #include <machine/tss.h>
44 #include <gdbthread.h>
47 #include <frame-unwind.h>
48 #include <i386-tdep.h>
55 kgdb_trgt_core_pcb(u_int cpuid)
57 return (kgdb_trgt_stop_pcb(cpuid, sizeof(struct pcb)));
61 kgdb_trgt_fetch_registers(int regno __unused)
66 kt = kgdb_thr_lookup_tid(ptid_get_pid(inferior_ptid));
69 if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
70 warnx("kvm_read: %s", kvm_geterr(kvm));
71 memset(&pcb, 0, sizeof(pcb));
73 supply_register(I386_EBX_REGNUM, (char *)&pcb.pcb_ebx);
74 supply_register(I386_ESP_REGNUM, (char *)&pcb.pcb_esp);
75 supply_register(I386_EBP_REGNUM, (char *)&pcb.pcb_ebp);
76 supply_register(I386_ESI_REGNUM, (char *)&pcb.pcb_esi);
77 supply_register(I386_EDI_REGNUM, (char *)&pcb.pcb_edi);
78 supply_register(I386_EIP_REGNUM, (char *)&pcb.pcb_eip);
82 kgdb_trgt_store_registers(int regno __unused)
84 fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
88 kgdb_trgt_new_objfile(struct objfile *objfile)
92 * In revision 1.117 of i386/i386/exception.S trap handlers
93 * were changed to pass trapframes by reference rather than
94 * by value. Detect this by seeing if the first instruction
95 * at the 'calltrap' label is a "push %esp" which has the
98 if (kgdb_parse("((char *)calltrap)[0]") == 0x54)
104 struct kgdb_tss_cache {
110 static int kgdb_trgt_tss_offset[15] = {
111 offsetof(struct i386tss, tss_eax),
112 offsetof(struct i386tss, tss_ecx),
113 offsetof(struct i386tss, tss_edx),
114 offsetof(struct i386tss, tss_ebx),
115 offsetof(struct i386tss, tss_esp),
116 offsetof(struct i386tss, tss_ebp),
117 offsetof(struct i386tss, tss_esi),
118 offsetof(struct i386tss, tss_edi),
119 offsetof(struct i386tss, tss_eip),
120 offsetof(struct i386tss, tss_eflags),
121 offsetof(struct i386tss, tss_cs),
122 offsetof(struct i386tss, tss_ss),
123 offsetof(struct i386tss, tss_ds),
124 offsetof(struct i386tss, tss_es),
125 offsetof(struct i386tss, tss_fs)
129 * If the current thread is executing on a CPU, fetch the common_tss
132 * This is painful because 'struct pcpu' is variant sized, so we can't
133 * use it. Instead, we lookup the GDT selector for this CPU and
134 * extract the base of the TSS from there.
137 kgdb_trgt_fetch_tss(void)
140 struct segment_descriptor sd;
141 uintptr_t addr, cpu0prvpage, tss;
143 kt = kgdb_thr_lookup_tid(ptid_get_pid(inferior_ptid));
144 if (kt == NULL || kt->cpu == NOCPU || kt->cpu < 0)
147 addr = kgdb_lookup("gdt");
150 addr += (kt->cpu * NGDT + GPROC0_SEL) * sizeof(sd);
151 if (kvm_read(kvm, addr, &sd, sizeof(sd)) != sizeof(sd)) {
152 warnx("kvm_read: %s", kvm_geterr(kvm));
155 if (sd.sd_type != SDT_SYS386BSY) {
156 warnx("descriptor is not a busy TSS");
159 tss = sd.sd_hibase << 24 | sd.sd_lobase;
162 * In SMP kernels, the TSS is stored as part of the per-CPU
163 * data. On older kernels, the CPU0's private page
164 * is stored at an address that isn't mapped in minidumps.
165 * However, the data is mapped at the alternate cpu0prvpage
166 * address. Thus, if the TSS is at the invalid address,
167 * change it to be relative to cpu0prvpage instead.
169 if (trunc_page(tss) == 0xffc00000) {
170 addr = kgdb_lookup("cpu0prvpage");
173 if (kvm_read(kvm, addr, &cpu0prvpage, sizeof(cpu0prvpage)) !=
174 sizeof(cpu0prvpage)) {
175 warnx("kvm_read: %s", kvm_geterr(kvm));
178 tss = cpu0prvpage + (tss & PAGE_MASK);
180 return ((CORE_ADDR)tss);
183 static struct kgdb_tss_cache *
184 kgdb_trgt_tss_cache(struct frame_info *next_frame, void **this_cache)
186 char buf[MAX_REGISTER_SIZE];
187 struct kgdb_tss_cache *cache;
191 cache = FRAME_OBSTACK_ZALLOC(struct kgdb_tss_cache);
193 cache->pc = frame_func_unwind(next_frame);
194 frame_unwind_register(next_frame, SP_REGNUM, buf);
195 cache->sp = extract_unsigned_integer(buf,
196 register_size(current_gdbarch, SP_REGNUM));
197 cache->tss = kgdb_trgt_fetch_tss();
203 kgdb_trgt_dblfault_this_id(struct frame_info *next_frame, void **this_cache,
204 struct frame_id *this_id)
206 struct kgdb_tss_cache *cache;
208 cache = kgdb_trgt_tss_cache(next_frame, this_cache);
209 *this_id = frame_id_build(cache->sp, cache->pc);
213 kgdb_trgt_dblfault_prev_register(struct frame_info *next_frame,
214 void **this_cache, int regnum, int *optimizedp, enum lval_type *lvalp,
215 CORE_ADDR *addrp, int *realnump, void *valuep)
217 char dummy_valuep[MAX_REGISTER_SIZE];
218 struct kgdb_tss_cache *cache;
221 regsz = register_size(current_gdbarch, regnum);
224 valuep = dummy_valuep;
225 memset(valuep, 0, regsz);
231 ofs = (regnum >= I386_EAX_REGNUM && regnum <= I386_FS_REGNUM)
232 ? kgdb_trgt_tss_offset[regnum] : -1;
236 cache = kgdb_trgt_tss_cache(next_frame, this_cache);
239 *addrp = cache->tss + ofs;
240 *lvalp = lval_memory;
241 target_read_memory(*addrp, valuep, regsz);
244 static const struct frame_unwind kgdb_trgt_dblfault_unwind = {
246 &kgdb_trgt_dblfault_this_id,
247 &kgdb_trgt_dblfault_prev_register
250 struct kgdb_frame_cache {
256 #define FT_INTRFRAME 2
257 #define FT_INTRTRAPFRAME 3
258 #define FT_TIMERFRAME 4
260 static int kgdb_trgt_frame_offset[15] = {
261 offsetof(struct trapframe, tf_eax),
262 offsetof(struct trapframe, tf_ecx),
263 offsetof(struct trapframe, tf_edx),
264 offsetof(struct trapframe, tf_ebx),
265 offsetof(struct trapframe, tf_esp),
266 offsetof(struct trapframe, tf_ebp),
267 offsetof(struct trapframe, tf_esi),
268 offsetof(struct trapframe, tf_edi),
269 offsetof(struct trapframe, tf_eip),
270 offsetof(struct trapframe, tf_eflags),
271 offsetof(struct trapframe, tf_cs),
272 offsetof(struct trapframe, tf_ss),
273 offsetof(struct trapframe, tf_ds),
274 offsetof(struct trapframe, tf_es),
275 offsetof(struct trapframe, tf_fs)
278 static struct kgdb_frame_cache *
279 kgdb_trgt_frame_cache(struct frame_info *next_frame, void **this_cache)
281 char buf[MAX_REGISTER_SIZE];
282 struct kgdb_frame_cache *cache;
285 uintptr_t addr, setidt_disp;
289 cache = FRAME_OBSTACK_ZALLOC(struct kgdb_frame_cache);
291 pcx = frame_pc_unwind(next_frame);
292 if (pcx >= PMAP_TRM_MIN_ADDRESS) {
293 addr = kgdb_lookup("setidt_disp");
295 if (kvm_read(kvm, addr, &setidt_disp,
296 sizeof(setidt_disp)) !=
298 warnx("kvm_read: %s", kvm_geterr(kvm));
304 find_pc_partial_function(cache->pc, &pname, NULL, NULL);
306 cache->frame_type = FT_NORMAL;
307 else if (strcmp(pname, "Xtimerint") == 0)
308 cache->frame_type = FT_TIMERFRAME;
309 else if (strcmp(pname, "Xcpustop") == 0 ||
310 strcmp(pname, "Xrendezvous") == 0 ||
311 strcmp(pname, "Xipi_intr_bitmap_handler") == 0 ||
312 strcmp(pname, "Xlazypmap") == 0)
313 cache->frame_type = FT_INTRTRAPFRAME;
315 cache->frame_type = FT_INTRFRAME;
316 frame_unwind_register(next_frame, SP_REGNUM, buf);
317 cache->sp = extract_unsigned_integer(buf,
318 register_size(current_gdbarch, SP_REGNUM));
324 kgdb_trgt_trapframe_this_id(struct frame_info *next_frame, void **this_cache,
325 struct frame_id *this_id)
327 struct kgdb_frame_cache *cache;
329 cache = kgdb_trgt_frame_cache(next_frame, this_cache);
330 *this_id = frame_id_build(cache->sp, cache->pc);
334 kgdb_trgt_trapframe_prev_register(struct frame_info *next_frame,
335 void **this_cache, int regnum, int *optimizedp, enum lval_type *lvalp,
336 CORE_ADDR *addrp, int *realnump, void *valuep)
338 char dummy_valuep[MAX_REGISTER_SIZE];
339 struct kgdb_frame_cache *cache;
342 regsz = register_size(current_gdbarch, regnum);
345 valuep = dummy_valuep;
346 memset(valuep, 0, regsz);
352 ofs = (regnum >= I386_EAX_REGNUM && regnum <= I386_FS_REGNUM)
353 ? kgdb_trgt_frame_offset[regnum] + ofs_fix : -1;
357 cache = kgdb_trgt_frame_cache(next_frame, this_cache);
358 switch (cache->frame_type) {
366 case FT_INTRTRAPFRAME:
370 fprintf_unfiltered(gdb_stderr, "Correct FT_XXX frame offsets "
371 "for %d\n", cache->frame_type);
374 *addrp = cache->sp + ofs;
375 *lvalp = lval_memory;
376 target_read_memory(*addrp, valuep, regsz);
379 static const struct frame_unwind kgdb_trgt_trapframe_unwind = {
381 &kgdb_trgt_trapframe_this_id,
382 &kgdb_trgt_trapframe_prev_register
385 const struct frame_unwind *
386 kgdb_trgt_trapframe_sniffer(struct frame_info *next_frame)
391 pc = frame_pc_unwind(next_frame);
392 if (pc >= PMAP_TRM_MIN_ADDRESS)
393 return (&kgdb_trgt_trapframe_unwind);
395 find_pc_partial_function(pc, &pname, NULL, NULL);
398 if (strcmp(pname, "dblfault_handler") == 0)
399 return (&kgdb_trgt_dblfault_unwind);
400 if (strcmp(pname, "calltrap") == 0 ||
401 (pname[0] == 'X' && pname[1] != '_'))
402 return (&kgdb_trgt_trapframe_unwind);
403 /* printf("%s: %llx =%s\n", __func__, pc, pname); */
408 * This function ensures, that the PC is inside the
409 * function section which is understood by GDB.
411 * Return 0 when fixup is necessary, -1 otherwise.
414 kgdb_trgt_pc_fixup(CORE_ADDR *pc __unused)