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>
32 #include <machine/pcb.h>
33 #include <machine/frame.h>
34 #include <machine/segments.h>
35 #include <machine/tss.h>
42 #include <gdbthread.h>
46 #include <frame-unwind.h>
47 #include <i386-tdep.h>
54 kgdb_trgt_fetch_registers(int regno __unused)
59 kt = kgdb_thr_lookup_tid(ptid_get_pid(inferior_ptid));
62 if (kvm_read(kvm, kt->pcb, &pcb, sizeof(pcb)) != sizeof(pcb)) {
63 warnx("kvm_read: %s", kvm_geterr(kvm));
64 memset(&pcb, 0, sizeof(pcb));
66 supply_register(I386_EBX_REGNUM, (char *)&pcb.pcb_ebx);
67 supply_register(I386_ESP_REGNUM, (char *)&pcb.pcb_esp);
68 supply_register(I386_EBP_REGNUM, (char *)&pcb.pcb_ebp);
69 supply_register(I386_ESI_REGNUM, (char *)&pcb.pcb_esi);
70 supply_register(I386_EDI_REGNUM, (char *)&pcb.pcb_edi);
71 supply_register(I386_EIP_REGNUM, (char *)&pcb.pcb_eip);
75 kgdb_trgt_store_registers(int regno __unused)
77 fprintf_unfiltered(gdb_stderr, "XXX: %s\n", __func__);
81 kgdb_trgt_new_objfile(struct objfile *objfile)
85 * In revision 1.117 of i386/i386/exception.S trap handlers
86 * were changed to pass trapframes by reference rather than
87 * by value. Detect this by seeing if the first instruction
88 * at the 'calltrap' label is a "push %esp" which has the
91 if (kgdb_parse("((char *)calltrap)[0]") == 0x54)
97 struct kgdb_tss_cache {
103 static int kgdb_trgt_tss_offset[15] = {
104 offsetof(struct i386tss, tss_eax),
105 offsetof(struct i386tss, tss_ecx),
106 offsetof(struct i386tss, tss_edx),
107 offsetof(struct i386tss, tss_ebx),
108 offsetof(struct i386tss, tss_esp),
109 offsetof(struct i386tss, tss_ebp),
110 offsetof(struct i386tss, tss_esi),
111 offsetof(struct i386tss, tss_edi),
112 offsetof(struct i386tss, tss_eip),
113 offsetof(struct i386tss, tss_eflags),
114 offsetof(struct i386tss, tss_cs),
115 offsetof(struct i386tss, tss_ss),
116 offsetof(struct i386tss, tss_ds),
117 offsetof(struct i386tss, tss_es),
118 offsetof(struct i386tss, tss_fs)
122 * If the current thread is executing on a CPU, fetch the common_tss
125 * This is painful because 'struct pcpu' is variant sized, so we can't
126 * use it. Instead, we lookup the GDT selector for this CPU and
127 * extract the base of the TSS from there.
130 kgdb_trgt_fetch_tss(void)
133 struct segment_descriptor sd;
134 uintptr_t addr, cpu0prvpage, tss;
136 kt = kgdb_thr_lookup_tid(ptid_get_pid(inferior_ptid));
137 if (kt == NULL || kt->cpu == NOCPU)
140 addr = kgdb_lookup("_gdt");
143 addr += (kt->cpu * NGDT + GPROC0_SEL) * sizeof(sd);
144 if (kvm_read(kvm, addr, &sd, sizeof(sd)) != sizeof(sd)) {
145 warnx("kvm_read: %s", kvm_geterr(kvm));
148 if (sd.sd_type != SDT_SYS386BSY) {
149 warnx("descriptor is not a busy TSS");
152 tss = sd.sd_hibase << 24 | sd.sd_lobase;
155 * In SMP kernels, the TSS is stored as part of the per-CPU
156 * data. On older kernels, the CPU0's private page
157 * is stored at an address that isn't mapped in minidumps.
158 * However, the data is mapped at the alternate cpu0prvpage
159 * address. Thus, if the TSS is at the invalid address,
160 * change it to be relative to cpu0prvpage instead.
162 if (trunc_page(tss) == 0xffc00000) {
163 addr = kgdb_lookup("_cpu0prvpage");
165 warnx("kvm_nlist(_cpu0prvpage): %s", kvm_geterr(kvm));
168 if (kvm_read(kvm, addr, &cpu0prvpage, sizeof(cpu0prvpage)) !=
169 sizeof(cpu0prvpage)) {
170 warnx("kvm_read: %s", kvm_geterr(kvm));
173 tss = cpu0prvpage + (tss & PAGE_MASK);
175 return ((CORE_ADDR)tss);
178 static struct kgdb_tss_cache *
179 kgdb_trgt_tss_cache(struct frame_info *next_frame, void **this_cache)
181 char buf[MAX_REGISTER_SIZE];
182 struct kgdb_tss_cache *cache;
186 cache = FRAME_OBSTACK_ZALLOC(struct kgdb_tss_cache);
188 cache->pc = frame_func_unwind(next_frame);
189 frame_unwind_register(next_frame, SP_REGNUM, buf);
190 cache->sp = extract_unsigned_integer(buf,
191 register_size(current_gdbarch, SP_REGNUM));
192 cache->tss = kgdb_trgt_fetch_tss();
198 kgdb_trgt_dblfault_this_id(struct frame_info *next_frame, void **this_cache,
199 struct frame_id *this_id)
201 struct kgdb_tss_cache *cache;
203 cache = kgdb_trgt_tss_cache(next_frame, this_cache);
204 *this_id = frame_id_build(cache->sp, cache->pc);
208 kgdb_trgt_dblfault_prev_register(struct frame_info *next_frame,
209 void **this_cache, int regnum, int *optimizedp, enum lval_type *lvalp,
210 CORE_ADDR *addrp, int *realnump, void *valuep)
212 char dummy_valuep[MAX_REGISTER_SIZE];
213 struct kgdb_tss_cache *cache;
216 regsz = register_size(current_gdbarch, regnum);
219 valuep = dummy_valuep;
220 memset(valuep, 0, regsz);
226 ofs = (regnum >= I386_EAX_REGNUM && regnum <= I386_FS_REGNUM)
227 ? kgdb_trgt_tss_offset[regnum] : -1;
231 cache = kgdb_trgt_tss_cache(next_frame, this_cache);
234 *addrp = cache->tss + ofs;
235 *lvalp = lval_memory;
236 target_read_memory(*addrp, valuep, regsz);
239 static const struct frame_unwind kgdb_trgt_dblfault_unwind = {
241 &kgdb_trgt_dblfault_this_id,
242 &kgdb_trgt_dblfault_prev_register
245 struct kgdb_frame_cache {
251 #define FT_INTRFRAME 2
252 #define FT_INTRTRAPFRAME 3
253 #define FT_TIMERFRAME 4
255 static int kgdb_trgt_frame_offset[15] = {
256 offsetof(struct trapframe, tf_eax),
257 offsetof(struct trapframe, tf_ecx),
258 offsetof(struct trapframe, tf_edx),
259 offsetof(struct trapframe, tf_ebx),
260 offsetof(struct trapframe, tf_esp),
261 offsetof(struct trapframe, tf_ebp),
262 offsetof(struct trapframe, tf_esi),
263 offsetof(struct trapframe, tf_edi),
264 offsetof(struct trapframe, tf_eip),
265 offsetof(struct trapframe, tf_eflags),
266 offsetof(struct trapframe, tf_cs),
267 offsetof(struct trapframe, tf_ss),
268 offsetof(struct trapframe, tf_ds),
269 offsetof(struct trapframe, tf_es),
270 offsetof(struct trapframe, tf_fs)
273 static struct kgdb_frame_cache *
274 kgdb_trgt_frame_cache(struct frame_info *next_frame, void **this_cache)
276 char buf[MAX_REGISTER_SIZE];
277 struct kgdb_frame_cache *cache;
282 cache = FRAME_OBSTACK_ZALLOC(struct kgdb_frame_cache);
284 cache->pc = frame_func_unwind(next_frame);
285 find_pc_partial_function(cache->pc, &pname, NULL, NULL);
287 cache->frame_type = FT_NORMAL;
288 else if (strcmp(pname, "Xtimerint") == 0)
289 cache->frame_type = FT_TIMERFRAME;
290 else if (strcmp(pname, "Xcpustop") == 0 ||
291 strcmp(pname, "Xrendezvous") == 0 ||
292 strcmp(pname, "Xipi_intr_bitmap_handler") == 0 ||
293 strcmp(pname, "Xlazypmap") == 0)
294 cache->frame_type = FT_INTRTRAPFRAME;
296 cache->frame_type = FT_INTRFRAME;
297 frame_unwind_register(next_frame, SP_REGNUM, buf);
298 cache->sp = extract_unsigned_integer(buf,
299 register_size(current_gdbarch, SP_REGNUM));
305 kgdb_trgt_trapframe_this_id(struct frame_info *next_frame, void **this_cache,
306 struct frame_id *this_id)
308 struct kgdb_frame_cache *cache;
310 cache = kgdb_trgt_frame_cache(next_frame, this_cache);
311 *this_id = frame_id_build(cache->sp, cache->pc);
315 kgdb_trgt_trapframe_prev_register(struct frame_info *next_frame,
316 void **this_cache, int regnum, int *optimizedp, enum lval_type *lvalp,
317 CORE_ADDR *addrp, int *realnump, void *valuep)
319 char dummy_valuep[MAX_REGISTER_SIZE];
320 struct kgdb_frame_cache *cache;
323 regsz = register_size(current_gdbarch, regnum);
326 valuep = dummy_valuep;
327 memset(valuep, 0, regsz);
333 ofs = (regnum >= I386_EAX_REGNUM && regnum <= I386_FS_REGNUM)
334 ? kgdb_trgt_frame_offset[regnum] + ofs_fix : -1;
338 cache = kgdb_trgt_frame_cache(next_frame, this_cache);
339 switch (cache->frame_type) {
347 case FT_INTRTRAPFRAME:
351 fprintf_unfiltered(gdb_stderr, "Correct FT_XXX frame offsets "
352 "for %d\n", cache->frame_type);
355 *addrp = cache->sp + ofs;
356 *lvalp = lval_memory;
357 target_read_memory(*addrp, valuep, regsz);
360 static const struct frame_unwind kgdb_trgt_trapframe_unwind = {
362 &kgdb_trgt_trapframe_this_id,
363 &kgdb_trgt_trapframe_prev_register
366 const struct frame_unwind *
367 kgdb_trgt_trapframe_sniffer(struct frame_info *next_frame)
372 pc = frame_pc_unwind(next_frame);
374 find_pc_partial_function(pc, &pname, NULL, NULL);
377 if (strcmp(pname, "dblfault_handler") == 0)
378 return (&kgdb_trgt_dblfault_unwind);
379 if (strcmp(pname, "calltrap") == 0 ||
380 (pname[0] == 'X' && pname[1] != '_'))
381 return (&kgdb_trgt_trapframe_unwind);
382 /* printf("%s: %llx =%s\n", __func__, pc, pname); */