ulong_t handle_exception(ulong_t sigcode, CPU_REGISTERS *ctx, struct kdebug_entry *entry) {
#ifdef DEBUG_GDB
kprintf("Enter KDB exception: Sigcode = %x (EIP=%x)\n", (unsigned)sigcode, ctx->eip);
#endif
if(!is_watch_entry(entry, ctx->eip) && !WANT_FAULT(sigcode)) {
#ifdef DEBUG_GDB
kprintf("Skip KDB exception: return %x\n", (unsigned)sigcode);
#endif
return sigcode;
}
ctx->efl &= ~X86_PSW_TF;
restore_break();
/*
* Goto GDB command interpreter.
*/
gdb_interface(entry, ctx, sigcode);
#ifdef DEBUG_GDB
kprintf("Leave KDB exception: return 0\n");
#endif
return (0);
}
/*
* Quickest way to gdb -- just pass a command string to pass through.
*/
int
gdb_pass_through(char *cmd, FILE *fptr, ulong flags)
{
struct gnu_request *req;
int retval;
if (CRASHDEBUG(1))
console("gdb_pass_through: [%s]\n", cmd);
req = (struct gnu_request *)GETBUF(sizeof(struct gnu_request));
req->buf = cmd;
if (fptr)
req->fp = fptr;
req->command = GNU_PASS_THROUGH;
req->flags = flags;
gdb_interface(req);
if ((req->flags & (GNU_RETURN_ON_ERROR|GNU_COMMAND_FAILED)) ==
(GNU_RETURN_ON_ERROR|GNU_COMMAND_FAILED))
retval = FALSE;
else
retval = TRUE;
FREEBUF(req);
return retval;
}
/*
* Check whether string in args[0] is a valid gdb command.
*/
int
is_gdb_command(int merge_orig_args, ulong flags)
{
int retval;
struct gnu_request *req;
if (!args[0])
return FALSE;
if (STREQ(args[0], "Q")) {
args[0] = "q";
return TRUE;
}
if (is_restricted_command(args[0], flags))
return FALSE;
req = (struct gnu_request *)GETBUF(sizeof(struct gnu_request));
req->buf = GETBUF(strlen(args[0])+1);
req->command = GNU_COMMAND_EXISTS;
req->name = args[0];
req->flags = GNU_RETURN_ON_ERROR;
req->fp = pc->nullfp;
gdb_interface(req);
if (req->flags & GNU_COMMAND_FAILED)
retval = FALSE;
else
retval = req->value;
FREEBUF(req->buf);
FREEBUF(req);
if (retval && merge_orig_args) {
int i;
for (i = argcnt; i; i--)
args[i] = args[i-1];
args[0] = "gdb";
argcnt++;
}
return retval;
}
void
gdb_session_init(void)
{
struct gnu_request *req;
int debug_data_pulled_in;
if (!have_partial_symbols() && !have_full_symbols())
no_debugging_data(FATAL);
/*
* Restore the SIGINT and SIGPIPE handlers, which got temporarily
* re-assigned by gdb. The SIGINT call also initializes GDB's
* SIGINT sigaction.
*/
SIGACTION(SIGINT, restart, &pc->sigaction, &pc->gdb_sigaction);
SIGACTION(SIGPIPE, SIG_IGN, &pc->sigaction, NULL);
if (!(pc->flags & DROP_CORE))
SIGACTION(SIGSEGV, restart, &pc->sigaction, NULL);
/*
* Set up pointers to gdb variables.
*/
#if defined(GDB_5_3) || defined(GDB_6_0) || defined(GDB_6_1)
gdb_output_format = &output_format;
gdb_print_max = &print_max;
gdb_prettyprint_structs = &prettyprint_structs;
gdb_prettyprint_arrays = &prettyprint_arrays;
gdb_repeat_count_threshold = &repeat_count_threshold;
gdb_stop_print_at_null = &stop_print_at_null;
gdb_output_radix = &output_radix;
#else
gdb_output_format = (int *)
gdb_user_print_option_address("output_format");
gdb_print_max = (unsigned int *)
gdb_user_print_option_address("print_max");
gdb_prettyprint_structs = (int *)
gdb_user_print_option_address("prettyprint_structs");
gdb_prettyprint_arrays = (int *)
gdb_user_print_option_address("prettyprint_arrays");
gdb_repeat_count_threshold = (int *)
gdb_user_print_option_address("repeat_count_threshold");
gdb_stop_print_at_null = (int *)
gdb_user_print_option_address("stop_print_at_null");
gdb_output_radix = (unsigned int *)
gdb_user_print_option_address("output_radix");
#endif
/*
* If the output radix is set via the --hex or --dec command line
* option, then pc->output_radix will be non-zero; otherwise use
* the gdb default.
*/
if (pc->output_radix) {
*gdb_output_radix = pc->output_radix;
*gdb_output_format = (*gdb_output_radix == 10) ? 0 : 'x';
}
switch (*gdb_output_radix)
{
case 10:
case 16:
pc->output_radix = *gdb_output_radix;
break;
default:
pc->output_radix = *gdb_output_radix = 10;
*gdb_output_format = 0;
}
*gdb_prettyprint_structs = 1;
*gdb_repeat_count_threshold = 0x7fffffff;
*gdb_print_max = 256;
#ifdef GDB_5_3
gdb_disassemble_from_exec = 0;
#endif
pc->flags |= GDB_INIT; /* set here so gdb_interface will work */
req = (struct gnu_request *)GETBUF(sizeof(struct gnu_request));
req->buf = GETBUF(BUFSIZE);
/*
* Make sure the namelist has symbolic data. Later versions of
* gcc may require that debug data be pulled in by printing a
* static kernel data structure.
*/
debug_data_pulled_in = FALSE;
retry:
BZERO(req->buf, BUFSIZE);
req->command = GNU_GET_DATATYPE;
req->name = XEN_HYPER_MODE() ? "page_info" : "task_struct";
req->flags = GNU_RETURN_ON_ERROR;
gdb_interface(req);
if (req->flags & GNU_COMMAND_FAILED) {
if (XEN_HYPER_MODE())
no_debugging_data(WARNING); /* just bail out */
if (!debug_data_pulled_in) {
if (CRASHDEBUG(1))
error(INFO,
"gdb_session_init: pulling in debug data by accessing init_mm.mmap %s\n",
symbol_exists("sysfs_mount") ?
"and syfs_mount" : "");
debug_data_pulled_in = TRUE;
req->command = GNU_PASS_THROUGH;
req->flags = GNU_RETURN_ON_ERROR|GNU_NO_READMEM;
req->name = NULL;
if (symbol_exists("sysfs_mount"))
sprintf(req->buf, "print sysfs_mount, init_mm.mmap");
else
sprintf(req->buf, "print init_mm.mmap");
gdb_interface(req);
if (!(req->flags & GNU_COMMAND_FAILED))
goto retry;
}
no_debugging_data(WARNING);
}
if (pc->flags & KERNEL_DEBUG_QUERY) {
fprintf(fp, "\n%s: %s: contains debugging data\n\n",
pc->program_name, pc->namelist);
if (REMOTE())
remote_exit();
clean_exit(0);
}
/*
* Set up any pre-ordained gdb settings here that can't be
* accessed directly.
*/
req->command = GNU_PASS_THROUGH;
req->name = NULL, req->flags = 0;
sprintf(req->buf, "set height 0");
gdb_interface(req);
req->command = GNU_PASS_THROUGH;
req->name = NULL, req->flags = 0;
sprintf(req->buf, "set width 0");
gdb_interface(req);
/*
* Patch gdb's symbol values with the correct values from either
* the System.map or non-debug vmlinux, whichever is in effect.
*/
if ((pc->flags & SYSMAP) || (kt->flags & (RELOC_SET|RELOC_FORCE)) ||
(pc->namelist_debug && !pc->debuginfo_file)) {
req->command = GNU_PATCH_SYMBOL_VALUES;
req->flags = GNU_RETURN_ON_ERROR;
gdb_interface(req);
if (req->flags & GNU_COMMAND_FAILED)
error(FATAL, "patching of gdb symbol values failed\n");
} else if (!(pc->flags & SILENT))
fprintf(fp, "\n");
FREEBUF(req->buf);
FREEBUF(req);
}
