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f8416aa2 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
53197fc4 JW |
2 | /* |
3 | * Kernel Debug Core | |
4 | * | |
5 | * Maintainer: Jason Wessel <jason.wessel@windriver.com> | |
6 | * | |
7 | * Copyright (C) 2000-2001 VERITAS Software Corporation. | |
8 | * Copyright (C) 2002-2004 Timesys Corporation | |
9 | * Copyright (C) 2003-2004 Amit S. Kale <amitkale@linsyssoft.com> | |
a2531293 | 10 | * Copyright (C) 2004 Pavel Machek <pavel@ucw.cz> |
53197fc4 JW |
11 | * Copyright (C) 2004-2006 Tom Rini <trini@kernel.crashing.org> |
12 | * Copyright (C) 2004-2006 LinSysSoft Technologies Pvt. Ltd. | |
13 | * Copyright (C) 2005-2009 Wind River Systems, Inc. | |
14 | * Copyright (C) 2007 MontaVista Software, Inc. | |
15 | * Copyright (C) 2008 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> | |
16 | * | |
17 | * Contributors at various stages not listed above: | |
18 | * Jason Wessel ( jason.wessel@windriver.com ) | |
19 | * George Anzinger <george@mvista.com> | |
20 | * Anurekh Saxena (anurekh.saxena@timesys.com) | |
21 | * Lake Stevens Instrument Division (Glenn Engel) | |
22 | * Jim Kingdon, Cygnus Support. | |
23 | * | |
24 | * Original KGDB stub: David Grothe <dave@gcom.com>, | |
25 | * Tigran Aivazian <tigran@sco.com> | |
53197fc4 JW |
26 | */ |
27 | ||
28 | #include <linux/kernel.h> | |
3f07c014 | 29 | #include <linux/sched/signal.h> |
53197fc4 | 30 | #include <linux/kgdb.h> |
f5316b4a | 31 | #include <linux/kdb.h> |
16559ae4 | 32 | #include <linux/serial_core.h> |
53197fc4 JW |
33 | #include <linux/reboot.h> |
34 | #include <linux/uaccess.h> | |
35 | #include <asm/cacheflush.h> | |
36 | #include <asm/unaligned.h> | |
37 | #include "debug_core.h" | |
38 | ||
39 | #define KGDB_MAX_THREAD_QUERY 17 | |
40 | ||
41 | /* Our I/O buffers. */ | |
42 | static char remcom_in_buffer[BUFMAX]; | |
43 | static char remcom_out_buffer[BUFMAX]; | |
f679c498 JW |
44 | static int gdbstub_use_prev_in_buf; |
45 | static int gdbstub_prev_in_buf_pos; | |
53197fc4 JW |
46 | |
47 | /* Storage for the registers, in GDB format. */ | |
48 | static unsigned long gdb_regs[(NUMREGBYTES + | |
49 | sizeof(unsigned long) - 1) / | |
50 | sizeof(unsigned long)]; | |
51 | ||
52 | /* | |
53 | * GDB remote protocol parser: | |
54 | */ | |
55 | ||
f5316b4a JW |
56 | #ifdef CONFIG_KGDB_KDB |
57 | static int gdbstub_read_wait(void) | |
58 | { | |
59 | int ret = -1; | |
60 | int i; | |
61 | ||
f679c498 JW |
62 | if (unlikely(gdbstub_use_prev_in_buf)) { |
63 | if (gdbstub_prev_in_buf_pos < gdbstub_use_prev_in_buf) | |
64 | return remcom_in_buffer[gdbstub_prev_in_buf_pos++]; | |
65 | else | |
66 | gdbstub_use_prev_in_buf = 0; | |
67 | } | |
68 | ||
f5316b4a JW |
69 | /* poll any additional I/O interfaces that are defined */ |
70 | while (ret < 0) | |
71 | for (i = 0; kdb_poll_funcs[i] != NULL; i++) { | |
72 | ret = kdb_poll_funcs[i](); | |
73 | if (ret > 0) | |
74 | break; | |
75 | } | |
76 | return ret; | |
77 | } | |
78 | #else | |
79 | static int gdbstub_read_wait(void) | |
80 | { | |
81 | int ret = dbg_io_ops->read_char(); | |
82 | while (ret == NO_POLL_CHAR) | |
83 | ret = dbg_io_ops->read_char(); | |
84 | return ret; | |
85 | } | |
86 | #endif | |
53197fc4 JW |
87 | /* scan for the sequence $<data>#<checksum> */ |
88 | static void get_packet(char *buffer) | |
89 | { | |
90 | unsigned char checksum; | |
91 | unsigned char xmitcsum; | |
92 | int count; | |
93 | char ch; | |
94 | ||
95 | do { | |
96 | /* | |
97 | * Spin and wait around for the start character, ignore all | |
98 | * other characters: | |
99 | */ | |
f5316b4a | 100 | while ((ch = (gdbstub_read_wait())) != '$') |
53197fc4 JW |
101 | /* nothing */; |
102 | ||
103 | kgdb_connected = 1; | |
104 | checksum = 0; | |
105 | xmitcsum = -1; | |
106 | ||
107 | count = 0; | |
108 | ||
109 | /* | |
110 | * now, read until a # or end of buffer is found: | |
111 | */ | |
112 | while (count < (BUFMAX - 1)) { | |
f5316b4a | 113 | ch = gdbstub_read_wait(); |
53197fc4 JW |
114 | if (ch == '#') |
115 | break; | |
116 | checksum = checksum + ch; | |
117 | buffer[count] = ch; | |
118 | count = count + 1; | |
119 | } | |
53197fc4 JW |
120 | |
121 | if (ch == '#') { | |
a9fa20a7 AS |
122 | xmitcsum = hex_to_bin(gdbstub_read_wait()) << 4; |
123 | xmitcsum += hex_to_bin(gdbstub_read_wait()); | |
53197fc4 JW |
124 | |
125 | if (checksum != xmitcsum) | |
126 | /* failed checksum */ | |
127 | dbg_io_ops->write_char('-'); | |
128 | else | |
129 | /* successful transfer */ | |
130 | dbg_io_ops->write_char('+'); | |
131 | if (dbg_io_ops->flush) | |
132 | dbg_io_ops->flush(); | |
133 | } | |
f679c498 | 134 | buffer[count] = 0; |
53197fc4 JW |
135 | } while (checksum != xmitcsum); |
136 | } | |
137 | ||
138 | /* | |
139 | * Send the packet in buffer. | |
140 | * Check for gdb connection if asked for. | |
141 | */ | |
142 | static void put_packet(char *buffer) | |
143 | { | |
144 | unsigned char checksum; | |
145 | int count; | |
146 | char ch; | |
147 | ||
148 | /* | |
149 | * $<packet info>#<checksum>. | |
150 | */ | |
151 | while (1) { | |
152 | dbg_io_ops->write_char('$'); | |
153 | checksum = 0; | |
154 | count = 0; | |
155 | ||
156 | while ((ch = buffer[count])) { | |
157 | dbg_io_ops->write_char(ch); | |
158 | checksum += ch; | |
159 | count++; | |
160 | } | |
161 | ||
162 | dbg_io_ops->write_char('#'); | |
163 | dbg_io_ops->write_char(hex_asc_hi(checksum)); | |
164 | dbg_io_ops->write_char(hex_asc_lo(checksum)); | |
165 | if (dbg_io_ops->flush) | |
166 | dbg_io_ops->flush(); | |
167 | ||
168 | /* Now see what we get in reply. */ | |
f5316b4a | 169 | ch = gdbstub_read_wait(); |
53197fc4 JW |
170 | |
171 | if (ch == 3) | |
f5316b4a | 172 | ch = gdbstub_read_wait(); |
53197fc4 JW |
173 | |
174 | /* If we get an ACK, we are done. */ | |
175 | if (ch == '+') | |
176 | return; | |
177 | ||
178 | /* | |
179 | * If we get the start of another packet, this means | |
180 | * that GDB is attempting to reconnect. We will NAK | |
181 | * the packet being sent, and stop trying to send this | |
182 | * packet. | |
183 | */ | |
184 | if (ch == '$') { | |
185 | dbg_io_ops->write_char('-'); | |
186 | if (dbg_io_ops->flush) | |
187 | dbg_io_ops->flush(); | |
188 | return; | |
189 | } | |
190 | } | |
191 | } | |
192 | ||
193 | static char gdbmsgbuf[BUFMAX + 1]; | |
194 | ||
195 | void gdbstub_msg_write(const char *s, int len) | |
196 | { | |
197 | char *bufptr; | |
198 | int wcount; | |
199 | int i; | |
200 | ||
a0de055c JW |
201 | if (len == 0) |
202 | len = strlen(s); | |
203 | ||
53197fc4 JW |
204 | /* 'O'utput */ |
205 | gdbmsgbuf[0] = 'O'; | |
206 | ||
207 | /* Fill and send buffers... */ | |
208 | while (len > 0) { | |
209 | bufptr = gdbmsgbuf + 1; | |
210 | ||
211 | /* Calculate how many this time */ | |
212 | if ((len << 1) > (BUFMAX - 2)) | |
213 | wcount = (BUFMAX - 2) >> 1; | |
214 | else | |
215 | wcount = len; | |
216 | ||
217 | /* Pack in hex chars */ | |
218 | for (i = 0; i < wcount; i++) | |
50e1499f | 219 | bufptr = hex_byte_pack(bufptr, s[i]); |
53197fc4 JW |
220 | *bufptr = '\0'; |
221 | ||
222 | /* Move up */ | |
223 | s += wcount; | |
224 | len -= wcount; | |
225 | ||
226 | /* Write packet */ | |
227 | put_packet(gdbmsgbuf); | |
228 | } | |
229 | } | |
230 | ||
231 | /* | |
232 | * Convert the memory pointed to by mem into hex, placing result in | |
233 | * buf. Return a pointer to the last char put in buf (null). May | |
234 | * return an error. | |
235 | */ | |
55751145 | 236 | char *kgdb_mem2hex(char *mem, char *buf, int count) |
53197fc4 JW |
237 | { |
238 | char *tmp; | |
239 | int err; | |
240 | ||
241 | /* | |
242 | * We use the upper half of buf as an intermediate buffer for the | |
243 | * raw memory copy. Hex conversion will work against this one. | |
244 | */ | |
245 | tmp = buf + count; | |
246 | ||
fe557319 | 247 | err = copy_from_kernel_nofault(tmp, mem, count); |
55751145 JW |
248 | if (err) |
249 | return NULL; | |
250 | while (count > 0) { | |
50e1499f | 251 | buf = hex_byte_pack(buf, *tmp); |
55751145 JW |
252 | tmp++; |
253 | count--; | |
53197fc4 | 254 | } |
55751145 | 255 | *buf = 0; |
53197fc4 | 256 | |
55751145 | 257 | return buf; |
53197fc4 JW |
258 | } |
259 | ||
260 | /* | |
261 | * Convert the hex array pointed to by buf into binary to be placed in | |
262 | * mem. Return a pointer to the character AFTER the last byte | |
263 | * written. May return an error. | |
264 | */ | |
265 | int kgdb_hex2mem(char *buf, char *mem, int count) | |
266 | { | |
267 | char *tmp_raw; | |
268 | char *tmp_hex; | |
269 | ||
270 | /* | |
271 | * We use the upper half of buf as an intermediate buffer for the | |
272 | * raw memory that is converted from hex. | |
273 | */ | |
274 | tmp_raw = buf + count * 2; | |
275 | ||
276 | tmp_hex = tmp_raw - 1; | |
277 | while (tmp_hex >= buf) { | |
278 | tmp_raw--; | |
a9fa20a7 AS |
279 | *tmp_raw = hex_to_bin(*tmp_hex--); |
280 | *tmp_raw |= hex_to_bin(*tmp_hex--) << 4; | |
53197fc4 JW |
281 | } |
282 | ||
fe557319 | 283 | return copy_to_kernel_nofault(mem, tmp_raw, count); |
53197fc4 JW |
284 | } |
285 | ||
286 | /* | |
287 | * While we find nice hex chars, build a long_val. | |
288 | * Return number of chars processed. | |
289 | */ | |
290 | int kgdb_hex2long(char **ptr, unsigned long *long_val) | |
291 | { | |
292 | int hex_val; | |
293 | int num = 0; | |
294 | int negate = 0; | |
295 | ||
296 | *long_val = 0; | |
297 | ||
298 | if (**ptr == '-') { | |
299 | negate = 1; | |
300 | (*ptr)++; | |
301 | } | |
302 | while (**ptr) { | |
a9fa20a7 | 303 | hex_val = hex_to_bin(**ptr); |
53197fc4 JW |
304 | if (hex_val < 0) |
305 | break; | |
306 | ||
307 | *long_val = (*long_val << 4) | hex_val; | |
308 | num++; | |
309 | (*ptr)++; | |
310 | } | |
311 | ||
312 | if (negate) | |
313 | *long_val = -*long_val; | |
314 | ||
315 | return num; | |
316 | } | |
317 | ||
318 | /* | |
319 | * Copy the binary array pointed to by buf into mem. Fix $, #, and | |
320 | * 0x7d escaped with 0x7d. Return -EFAULT on failure or 0 on success. | |
2bbd9b0f | 321 | * The input buf is overwritten with the result to write to mem. |
53197fc4 JW |
322 | */ |
323 | static int kgdb_ebin2mem(char *buf, char *mem, int count) | |
324 | { | |
325 | int size = 0; | |
326 | char *c = buf; | |
327 | ||
328 | while (count-- > 0) { | |
329 | c[size] = *buf++; | |
330 | if (c[size] == 0x7d) | |
331 | c[size] = *buf++ ^ 0x20; | |
332 | size++; | |
333 | } | |
334 | ||
fe557319 | 335 | return copy_to_kernel_nofault(mem, c, size); |
53197fc4 JW |
336 | } |
337 | ||
534af108 JW |
338 | #if DBG_MAX_REG_NUM > 0 |
339 | void pt_regs_to_gdb_regs(unsigned long *gdb_regs, struct pt_regs *regs) | |
340 | { | |
341 | int i; | |
342 | int idx = 0; | |
343 | char *ptr = (char *)gdb_regs; | |
344 | ||
345 | for (i = 0; i < DBG_MAX_REG_NUM; i++) { | |
346 | dbg_get_reg(i, ptr + idx, regs); | |
347 | idx += dbg_reg_def[i].size; | |
348 | } | |
349 | } | |
350 | ||
351 | void gdb_regs_to_pt_regs(unsigned long *gdb_regs, struct pt_regs *regs) | |
352 | { | |
353 | int i; | |
354 | int idx = 0; | |
355 | char *ptr = (char *)gdb_regs; | |
356 | ||
357 | for (i = 0; i < DBG_MAX_REG_NUM; i++) { | |
358 | dbg_set_reg(i, ptr + idx, regs); | |
359 | idx += dbg_reg_def[i].size; | |
360 | } | |
361 | } | |
362 | #endif /* DBG_MAX_REG_NUM > 0 */ | |
363 | ||
53197fc4 JW |
364 | /* Write memory due to an 'M' or 'X' packet. */ |
365 | static int write_mem_msg(int binary) | |
366 | { | |
367 | char *ptr = &remcom_in_buffer[1]; | |
368 | unsigned long addr; | |
369 | unsigned long length; | |
370 | int err; | |
371 | ||
372 | if (kgdb_hex2long(&ptr, &addr) > 0 && *(ptr++) == ',' && | |
373 | kgdb_hex2long(&ptr, &length) > 0 && *(ptr++) == ':') { | |
374 | if (binary) | |
375 | err = kgdb_ebin2mem(ptr, (char *)addr, length); | |
376 | else | |
377 | err = kgdb_hex2mem(ptr, (char *)addr, length); | |
378 | if (err) | |
379 | return err; | |
380 | if (CACHE_FLUSH_IS_SAFE) | |
381 | flush_icache_range(addr, addr + length); | |
382 | return 0; | |
383 | } | |
384 | ||
385 | return -EINVAL; | |
386 | } | |
387 | ||
388 | static void error_packet(char *pkt, int error) | |
389 | { | |
390 | error = -error; | |
391 | pkt[0] = 'E'; | |
392 | pkt[1] = hex_asc[(error / 10)]; | |
393 | pkt[2] = hex_asc[(error % 10)]; | |
394 | pkt[3] = '\0'; | |
395 | } | |
396 | ||
397 | /* | |
398 | * Thread ID accessors. We represent a flat TID space to GDB, where | |
399 | * the per CPU idle threads (which under Linux all have PID 0) are | |
400 | * remapped to negative TIDs. | |
401 | */ | |
402 | ||
84a0bd5b | 403 | #define BUF_THREAD_ID_SIZE 8 |
53197fc4 JW |
404 | |
405 | static char *pack_threadid(char *pkt, unsigned char *id) | |
406 | { | |
84a0bd5b JW |
407 | unsigned char *limit; |
408 | int lzero = 1; | |
409 | ||
410 | limit = id + (BUF_THREAD_ID_SIZE / 2); | |
411 | while (id < limit) { | |
412 | if (!lzero || *id != 0) { | |
50e1499f | 413 | pkt = hex_byte_pack(pkt, *id); |
84a0bd5b JW |
414 | lzero = 0; |
415 | } | |
416 | id++; | |
417 | } | |
53197fc4 | 418 | |
84a0bd5b | 419 | if (lzero) |
50e1499f | 420 | pkt = hex_byte_pack(pkt, 0); |
53197fc4 JW |
421 | |
422 | return pkt; | |
423 | } | |
424 | ||
425 | static void int_to_threadref(unsigned char *id, int value) | |
426 | { | |
84a0bd5b | 427 | put_unaligned_be32(value, id); |
53197fc4 JW |
428 | } |
429 | ||
430 | static struct task_struct *getthread(struct pt_regs *regs, int tid) | |
431 | { | |
432 | /* | |
433 | * Non-positive TIDs are remapped to the cpu shadow information | |
434 | */ | |
435 | if (tid == 0 || tid == -1) | |
436 | tid = -atomic_read(&kgdb_active) - 2; | |
437 | if (tid < -1 && tid > -NR_CPUS - 2) { | |
438 | if (kgdb_info[-tid - 2].task) | |
439 | return kgdb_info[-tid - 2].task; | |
440 | else | |
441 | return idle_task(-tid - 2); | |
442 | } | |
443 | if (tid <= 0) { | |
444 | printk(KERN_ERR "KGDB: Internal thread select error\n"); | |
445 | dump_stack(); | |
446 | return NULL; | |
447 | } | |
448 | ||
449 | /* | |
450 | * find_task_by_pid_ns() does not take the tasklist lock anymore | |
451 | * but is nicely RCU locked - hence is a pretty resilient | |
452 | * thing to use: | |
453 | */ | |
454 | return find_task_by_pid_ns(tid, &init_pid_ns); | |
455 | } | |
456 | ||
457 | ||
458 | /* | |
459 | * Remap normal tasks to their real PID, | |
460 | * CPU shadow threads are mapped to -CPU - 2 | |
461 | */ | |
462 | static inline int shadow_pid(int realpid) | |
463 | { | |
464 | if (realpid) | |
465 | return realpid; | |
466 | ||
467 | return -raw_smp_processor_id() - 2; | |
468 | } | |
469 | ||
470 | /* | |
471 | * All the functions that start with gdb_cmd are the various | |
472 | * operations to implement the handlers for the gdbserial protocol | |
473 | * where KGDB is communicating with an external debugger | |
474 | */ | |
475 | ||
476 | /* Handle the '?' status packets */ | |
477 | static void gdb_cmd_status(struct kgdb_state *ks) | |
478 | { | |
479 | /* | |
480 | * We know that this packet is only sent | |
481 | * during initial connect. So to be safe, | |
482 | * we clear out our breakpoints now in case | |
483 | * GDB is reconnecting. | |
484 | */ | |
485 | dbg_remove_all_break(); | |
486 | ||
487 | remcom_out_buffer[0] = 'S'; | |
50e1499f | 488 | hex_byte_pack(&remcom_out_buffer[1], ks->signo); |
53197fc4 JW |
489 | } |
490 | ||
55751145 | 491 | static void gdb_get_regs_helper(struct kgdb_state *ks) |
53197fc4 JW |
492 | { |
493 | struct task_struct *thread; | |
494 | void *local_debuggerinfo; | |
495 | int i; | |
496 | ||
497 | thread = kgdb_usethread; | |
498 | if (!thread) { | |
499 | thread = kgdb_info[ks->cpu].task; | |
500 | local_debuggerinfo = kgdb_info[ks->cpu].debuggerinfo; | |
501 | } else { | |
502 | local_debuggerinfo = NULL; | |
503 | for_each_online_cpu(i) { | |
504 | /* | |
505 | * Try to find the task on some other | |
506 | * or possibly this node if we do not | |
507 | * find the matching task then we try | |
508 | * to approximate the results. | |
509 | */ | |
510 | if (thread == kgdb_info[i].task) | |
511 | local_debuggerinfo = kgdb_info[i].debuggerinfo; | |
512 | } | |
513 | } | |
514 | ||
515 | /* | |
516 | * All threads that don't have debuggerinfo should be | |
517 | * in schedule() sleeping, since all other CPUs | |
518 | * are in kgdb_wait, and thus have debuggerinfo. | |
519 | */ | |
520 | if (local_debuggerinfo) { | |
521 | pt_regs_to_gdb_regs(gdb_regs, local_debuggerinfo); | |
522 | } else { | |
523 | /* | |
524 | * Pull stuff saved during switch_to; nothing | |
525 | * else is accessible (or even particularly | |
526 | * relevant). | |
527 | * | |
528 | * This should be enough for a stack trace. | |
529 | */ | |
530 | sleeping_thread_to_gdb_regs(gdb_regs, thread); | |
531 | } | |
55751145 JW |
532 | } |
533 | ||
534 | /* Handle the 'g' get registers request */ | |
535 | static void gdb_cmd_getregs(struct kgdb_state *ks) | |
536 | { | |
537 | gdb_get_regs_helper(ks); | |
53197fc4 JW |
538 | kgdb_mem2hex((char *)gdb_regs, remcom_out_buffer, NUMREGBYTES); |
539 | } | |
540 | ||
541 | /* Handle the 'G' set registers request */ | |
542 | static void gdb_cmd_setregs(struct kgdb_state *ks) | |
543 | { | |
544 | kgdb_hex2mem(&remcom_in_buffer[1], (char *)gdb_regs, NUMREGBYTES); | |
545 | ||
546 | if (kgdb_usethread && kgdb_usethread != current) { | |
547 | error_packet(remcom_out_buffer, -EINVAL); | |
548 | } else { | |
549 | gdb_regs_to_pt_regs(gdb_regs, ks->linux_regs); | |
550 | strcpy(remcom_out_buffer, "OK"); | |
551 | } | |
552 | } | |
553 | ||
554 | /* Handle the 'm' memory read bytes */ | |
555 | static void gdb_cmd_memread(struct kgdb_state *ks) | |
556 | { | |
557 | char *ptr = &remcom_in_buffer[1]; | |
558 | unsigned long length; | |
559 | unsigned long addr; | |
55751145 | 560 | char *err; |
53197fc4 JW |
561 | |
562 | if (kgdb_hex2long(&ptr, &addr) > 0 && *ptr++ == ',' && | |
563 | kgdb_hex2long(&ptr, &length) > 0) { | |
564 | err = kgdb_mem2hex((char *)addr, remcom_out_buffer, length); | |
55751145 JW |
565 | if (!err) |
566 | error_packet(remcom_out_buffer, -EINVAL); | |
53197fc4 JW |
567 | } else { |
568 | error_packet(remcom_out_buffer, -EINVAL); | |
569 | } | |
570 | } | |
571 | ||
572 | /* Handle the 'M' memory write bytes */ | |
573 | static void gdb_cmd_memwrite(struct kgdb_state *ks) | |
574 | { | |
575 | int err = write_mem_msg(0); | |
576 | ||
577 | if (err) | |
578 | error_packet(remcom_out_buffer, err); | |
579 | else | |
580 | strcpy(remcom_out_buffer, "OK"); | |
581 | } | |
582 | ||
55751145 JW |
583 | #if DBG_MAX_REG_NUM > 0 |
584 | static char *gdb_hex_reg_helper(int regnum, char *out) | |
585 | { | |
586 | int i; | |
587 | int offset = 0; | |
588 | ||
589 | for (i = 0; i < regnum; i++) | |
590 | offset += dbg_reg_def[i].size; | |
591 | return kgdb_mem2hex((char *)gdb_regs + offset, out, | |
592 | dbg_reg_def[i].size); | |
593 | } | |
594 | ||
cbd026e1 | 595 | /* Handle the 'p' individual register get */ |
55751145 JW |
596 | static void gdb_cmd_reg_get(struct kgdb_state *ks) |
597 | { | |
598 | unsigned long regnum; | |
599 | char *ptr = &remcom_in_buffer[1]; | |
600 | ||
601 | kgdb_hex2long(&ptr, ®num); | |
602 | if (regnum >= DBG_MAX_REG_NUM) { | |
603 | error_packet(remcom_out_buffer, -EINVAL); | |
604 | return; | |
605 | } | |
606 | gdb_get_regs_helper(ks); | |
607 | gdb_hex_reg_helper(regnum, remcom_out_buffer); | |
608 | } | |
609 | ||
cbd026e1 | 610 | /* Handle the 'P' individual register set */ |
55751145 JW |
611 | static void gdb_cmd_reg_set(struct kgdb_state *ks) |
612 | { | |
613 | unsigned long regnum; | |
614 | char *ptr = &remcom_in_buffer[1]; | |
6d855b1d | 615 | int i = 0; |
55751145 JW |
616 | |
617 | kgdb_hex2long(&ptr, ®num); | |
618 | if (*ptr++ != '=' || | |
619 | !(!kgdb_usethread || kgdb_usethread == current) || | |
620 | !dbg_get_reg(regnum, gdb_regs, ks->linux_regs)) { | |
621 | error_packet(remcom_out_buffer, -EINVAL); | |
622 | return; | |
623 | } | |
6d855b1d JW |
624 | memset(gdb_regs, 0, sizeof(gdb_regs)); |
625 | while (i < sizeof(gdb_regs) * 2) | |
626 | if (hex_to_bin(ptr[i]) >= 0) | |
627 | i++; | |
628 | else | |
629 | break; | |
630 | i = i / 2; | |
631 | kgdb_hex2mem(ptr, (char *)gdb_regs, i); | |
55751145 JW |
632 | dbg_set_reg(regnum, gdb_regs, ks->linux_regs); |
633 | strcpy(remcom_out_buffer, "OK"); | |
634 | } | |
635 | #endif /* DBG_MAX_REG_NUM > 0 */ | |
636 | ||
53197fc4 JW |
637 | /* Handle the 'X' memory binary write bytes */ |
638 | static void gdb_cmd_binwrite(struct kgdb_state *ks) | |
639 | { | |
640 | int err = write_mem_msg(1); | |
641 | ||
642 | if (err) | |
643 | error_packet(remcom_out_buffer, err); | |
644 | else | |
645 | strcpy(remcom_out_buffer, "OK"); | |
646 | } | |
647 | ||
648 | /* Handle the 'D' or 'k', detach or kill packets */ | |
649 | static void gdb_cmd_detachkill(struct kgdb_state *ks) | |
650 | { | |
651 | int error; | |
652 | ||
653 | /* The detach case */ | |
654 | if (remcom_in_buffer[0] == 'D') { | |
655 | error = dbg_remove_all_break(); | |
656 | if (error < 0) { | |
657 | error_packet(remcom_out_buffer, error); | |
658 | } else { | |
659 | strcpy(remcom_out_buffer, "OK"); | |
660 | kgdb_connected = 0; | |
661 | } | |
662 | put_packet(remcom_out_buffer); | |
663 | } else { | |
664 | /* | |
665 | * Assume the kill case, with no exit code checking, | |
666 | * trying to force detach the debugger: | |
667 | */ | |
668 | dbg_remove_all_break(); | |
669 | kgdb_connected = 0; | |
670 | } | |
671 | } | |
672 | ||
673 | /* Handle the 'R' reboot packets */ | |
674 | static int gdb_cmd_reboot(struct kgdb_state *ks) | |
675 | { | |
676 | /* For now, only honor R0 */ | |
677 | if (strcmp(remcom_in_buffer, "R0") == 0) { | |
678 | printk(KERN_CRIT "Executing emergency reboot\n"); | |
679 | strcpy(remcom_out_buffer, "OK"); | |
680 | put_packet(remcom_out_buffer); | |
681 | ||
682 | /* | |
683 | * Execution should not return from | |
684 | * machine_emergency_restart() | |
685 | */ | |
686 | machine_emergency_restart(); | |
687 | kgdb_connected = 0; | |
688 | ||
689 | return 1; | |
690 | } | |
691 | return 0; | |
692 | } | |
693 | ||
694 | /* Handle the 'q' query packets */ | |
695 | static void gdb_cmd_query(struct kgdb_state *ks) | |
696 | { | |
697 | struct task_struct *g; | |
698 | struct task_struct *p; | |
84a0bd5b | 699 | unsigned char thref[BUF_THREAD_ID_SIZE]; |
53197fc4 JW |
700 | char *ptr; |
701 | int i; | |
702 | int cpu; | |
703 | int finished = 0; | |
704 | ||
705 | switch (remcom_in_buffer[1]) { | |
706 | case 's': | |
707 | case 'f': | |
fb82c0ff | 708 | if (memcmp(remcom_in_buffer + 2, "ThreadInfo", 10)) |
53197fc4 | 709 | break; |
53197fc4 JW |
710 | |
711 | i = 0; | |
712 | remcom_out_buffer[0] = 'm'; | |
713 | ptr = remcom_out_buffer + 1; | |
714 | if (remcom_in_buffer[1] == 'f') { | |
715 | /* Each cpu is a shadow thread */ | |
716 | for_each_online_cpu(cpu) { | |
717 | ks->thr_query = 0; | |
718 | int_to_threadref(thref, -cpu - 2); | |
84a0bd5b | 719 | ptr = pack_threadid(ptr, thref); |
53197fc4 JW |
720 | *(ptr++) = ','; |
721 | i++; | |
722 | } | |
723 | } | |
724 | ||
ece4ceaf | 725 | for_each_process_thread(g, p) { |
53197fc4 JW |
726 | if (i >= ks->thr_query && !finished) { |
727 | int_to_threadref(thref, p->pid); | |
84a0bd5b | 728 | ptr = pack_threadid(ptr, thref); |
53197fc4 JW |
729 | *(ptr++) = ','; |
730 | ks->thr_query++; | |
731 | if (ks->thr_query % KGDB_MAX_THREAD_QUERY == 0) | |
732 | finished = 1; | |
733 | } | |
734 | i++; | |
ece4ceaf | 735 | } |
53197fc4 JW |
736 | |
737 | *(--ptr) = '\0'; | |
738 | break; | |
739 | ||
740 | case 'C': | |
741 | /* Current thread id */ | |
742 | strcpy(remcom_out_buffer, "QC"); | |
743 | ks->threadid = shadow_pid(current->pid); | |
744 | int_to_threadref(thref, ks->threadid); | |
745 | pack_threadid(remcom_out_buffer + 2, thref); | |
746 | break; | |
747 | case 'T': | |
fb82c0ff | 748 | if (memcmp(remcom_in_buffer + 1, "ThreadExtraInfo,", 16)) |
53197fc4 | 749 | break; |
fb82c0ff | 750 | |
53197fc4 JW |
751 | ks->threadid = 0; |
752 | ptr = remcom_in_buffer + 17; | |
753 | kgdb_hex2long(&ptr, &ks->threadid); | |
754 | if (!getthread(ks->linux_regs, ks->threadid)) { | |
755 | error_packet(remcom_out_buffer, -EINVAL); | |
756 | break; | |
757 | } | |
758 | if ((int)ks->threadid > 0) { | |
759 | kgdb_mem2hex(getthread(ks->linux_regs, | |
760 | ks->threadid)->comm, | |
761 | remcom_out_buffer, 16); | |
762 | } else { | |
763 | static char tmpstr[23 + BUF_THREAD_ID_SIZE]; | |
764 | ||
765 | sprintf(tmpstr, "shadowCPU%d", | |
766 | (int)(-ks->threadid - 2)); | |
767 | kgdb_mem2hex(tmpstr, remcom_out_buffer, strlen(tmpstr)); | |
768 | } | |
769 | break; | |
a0de055c JW |
770 | #ifdef CONFIG_KGDB_KDB |
771 | case 'R': | |
772 | if (strncmp(remcom_in_buffer, "qRcmd,", 6) == 0) { | |
773 | int len = strlen(remcom_in_buffer + 6); | |
774 | ||
775 | if ((len % 2) != 0) { | |
776 | strcpy(remcom_out_buffer, "E01"); | |
777 | break; | |
778 | } | |
779 | kgdb_hex2mem(remcom_in_buffer + 6, | |
780 | remcom_out_buffer, len); | |
781 | len = len / 2; | |
782 | remcom_out_buffer[len++] = 0; | |
783 | ||
00370b8f | 784 | kdb_common_init_state(ks); |
a0de055c | 785 | kdb_parse(remcom_out_buffer); |
00370b8f MK |
786 | kdb_common_deinit_state(); |
787 | ||
a0de055c JW |
788 | strcpy(remcom_out_buffer, "OK"); |
789 | } | |
790 | break; | |
791 | #endif | |
8c080d3a VC |
792 | #ifdef CONFIG_HAVE_ARCH_KGDB_QXFER_PKT |
793 | case 'S': | |
794 | if (!strncmp(remcom_in_buffer, "qSupported:", 11)) | |
795 | strcpy(remcom_out_buffer, kgdb_arch_gdb_stub_feature); | |
796 | break; | |
797 | case 'X': | |
798 | if (!strncmp(remcom_in_buffer, "qXfer:", 6)) | |
799 | kgdb_arch_handle_qxfer_pkt(remcom_in_buffer, | |
800 | remcom_out_buffer); | |
801 | break; | |
802 | #endif | |
803 | default: | |
804 | break; | |
53197fc4 JW |
805 | } |
806 | } | |
807 | ||
808 | /* Handle the 'H' task query packets */ | |
809 | static void gdb_cmd_task(struct kgdb_state *ks) | |
810 | { | |
811 | struct task_struct *thread; | |
812 | char *ptr; | |
813 | ||
814 | switch (remcom_in_buffer[1]) { | |
815 | case 'g': | |
816 | ptr = &remcom_in_buffer[2]; | |
817 | kgdb_hex2long(&ptr, &ks->threadid); | |
818 | thread = getthread(ks->linux_regs, ks->threadid); | |
819 | if (!thread && ks->threadid > 0) { | |
820 | error_packet(remcom_out_buffer, -EINVAL); | |
821 | break; | |
822 | } | |
823 | kgdb_usethread = thread; | |
824 | ks->kgdb_usethreadid = ks->threadid; | |
825 | strcpy(remcom_out_buffer, "OK"); | |
826 | break; | |
827 | case 'c': | |
828 | ptr = &remcom_in_buffer[2]; | |
829 | kgdb_hex2long(&ptr, &ks->threadid); | |
830 | if (!ks->threadid) { | |
831 | kgdb_contthread = NULL; | |
832 | } else { | |
833 | thread = getthread(ks->linux_regs, ks->threadid); | |
834 | if (!thread && ks->threadid > 0) { | |
835 | error_packet(remcom_out_buffer, -EINVAL); | |
836 | break; | |
837 | } | |
838 | kgdb_contthread = thread; | |
839 | } | |
840 | strcpy(remcom_out_buffer, "OK"); | |
841 | break; | |
842 | } | |
843 | } | |
844 | ||
845 | /* Handle the 'T' thread query packets */ | |
846 | static void gdb_cmd_thread(struct kgdb_state *ks) | |
847 | { | |
848 | char *ptr = &remcom_in_buffer[1]; | |
849 | struct task_struct *thread; | |
850 | ||
851 | kgdb_hex2long(&ptr, &ks->threadid); | |
852 | thread = getthread(ks->linux_regs, ks->threadid); | |
853 | if (thread) | |
854 | strcpy(remcom_out_buffer, "OK"); | |
855 | else | |
856 | error_packet(remcom_out_buffer, -EINVAL); | |
857 | } | |
858 | ||
859 | /* Handle the 'z' or 'Z' breakpoint remove or set packets */ | |
860 | static void gdb_cmd_break(struct kgdb_state *ks) | |
861 | { | |
862 | /* | |
863 | * Since GDB-5.3, it's been drafted that '0' is a software | |
864 | * breakpoint, '1' is a hardware breakpoint, so let's do that. | |
865 | */ | |
866 | char *bpt_type = &remcom_in_buffer[1]; | |
867 | char *ptr = &remcom_in_buffer[2]; | |
868 | unsigned long addr; | |
869 | unsigned long length; | |
870 | int error = 0; | |
871 | ||
872 | if (arch_kgdb_ops.set_hw_breakpoint && *bpt_type >= '1') { | |
873 | /* Unsupported */ | |
874 | if (*bpt_type > '4') | |
875 | return; | |
876 | } else { | |
877 | if (*bpt_type != '0' && *bpt_type != '1') | |
878 | /* Unsupported. */ | |
879 | return; | |
880 | } | |
881 | ||
882 | /* | |
883 | * Test if this is a hardware breakpoint, and | |
884 | * if we support it: | |
885 | */ | |
886 | if (*bpt_type == '1' && !(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT)) | |
887 | /* Unsupported. */ | |
888 | return; | |
889 | ||
890 | if (*(ptr++) != ',') { | |
891 | error_packet(remcom_out_buffer, -EINVAL); | |
892 | return; | |
893 | } | |
894 | if (!kgdb_hex2long(&ptr, &addr)) { | |
895 | error_packet(remcom_out_buffer, -EINVAL); | |
896 | return; | |
897 | } | |
898 | if (*(ptr++) != ',' || | |
899 | !kgdb_hex2long(&ptr, &length)) { | |
900 | error_packet(remcom_out_buffer, -EINVAL); | |
901 | return; | |
902 | } | |
903 | ||
904 | if (remcom_in_buffer[0] == 'Z' && *bpt_type == '0') | |
905 | error = dbg_set_sw_break(addr); | |
906 | else if (remcom_in_buffer[0] == 'z' && *bpt_type == '0') | |
907 | error = dbg_remove_sw_break(addr); | |
908 | else if (remcom_in_buffer[0] == 'Z') | |
909 | error = arch_kgdb_ops.set_hw_breakpoint(addr, | |
910 | (int)length, *bpt_type - '0'); | |
911 | else if (remcom_in_buffer[0] == 'z') | |
912 | error = arch_kgdb_ops.remove_hw_breakpoint(addr, | |
913 | (int) length, *bpt_type - '0'); | |
914 | ||
915 | if (error == 0) | |
916 | strcpy(remcom_out_buffer, "OK"); | |
917 | else | |
918 | error_packet(remcom_out_buffer, error); | |
919 | } | |
920 | ||
921 | /* Handle the 'C' signal / exception passing packets */ | |
922 | static int gdb_cmd_exception_pass(struct kgdb_state *ks) | |
923 | { | |
924 | /* C09 == pass exception | |
925 | * C15 == detach kgdb, pass exception | |
926 | */ | |
927 | if (remcom_in_buffer[1] == '0' && remcom_in_buffer[2] == '9') { | |
928 | ||
929 | ks->pass_exception = 1; | |
930 | remcom_in_buffer[0] = 'c'; | |
931 | ||
932 | } else if (remcom_in_buffer[1] == '1' && remcom_in_buffer[2] == '5') { | |
933 | ||
934 | ks->pass_exception = 1; | |
935 | remcom_in_buffer[0] = 'D'; | |
936 | dbg_remove_all_break(); | |
937 | kgdb_connected = 0; | |
938 | return 1; | |
939 | ||
940 | } else { | |
941 | gdbstub_msg_write("KGDB only knows signal 9 (pass)" | |
942 | " and 15 (pass and disconnect)\n" | |
943 | "Executing a continue without signal passing\n", 0); | |
944 | remcom_in_buffer[0] = 'c'; | |
945 | } | |
946 | ||
947 | /* Indicate fall through */ | |
948 | return -1; | |
949 | } | |
950 | ||
951 | /* | |
2bbd9b0f | 952 | * This function performs all gdbserial command processing |
53197fc4 JW |
953 | */ |
954 | int gdb_serial_stub(struct kgdb_state *ks) | |
955 | { | |
956 | int error = 0; | |
957 | int tmp; | |
958 | ||
55751145 | 959 | /* Initialize comm buffer and globals. */ |
53197fc4 | 960 | memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer)); |
55751145 JW |
961 | kgdb_usethread = kgdb_info[ks->cpu].task; |
962 | ks->kgdb_usethreadid = shadow_pid(kgdb_info[ks->cpu].task->pid); | |
963 | ks->pass_exception = 0; | |
53197fc4 JW |
964 | |
965 | if (kgdb_connected) { | |
84a0bd5b | 966 | unsigned char thref[BUF_THREAD_ID_SIZE]; |
53197fc4 JW |
967 | char *ptr; |
968 | ||
969 | /* Reply to host that an exception has occurred */ | |
970 | ptr = remcom_out_buffer; | |
971 | *ptr++ = 'T'; | |
50e1499f | 972 | ptr = hex_byte_pack(ptr, ks->signo); |
53197fc4 JW |
973 | ptr += strlen(strcpy(ptr, "thread:")); |
974 | int_to_threadref(thref, shadow_pid(current->pid)); | |
975 | ptr = pack_threadid(ptr, thref); | |
976 | *ptr++ = ';'; | |
977 | put_packet(remcom_out_buffer); | |
978 | } | |
979 | ||
53197fc4 JW |
980 | while (1) { |
981 | error = 0; | |
982 | ||
983 | /* Clear the out buffer. */ | |
984 | memset(remcom_out_buffer, 0, sizeof(remcom_out_buffer)); | |
985 | ||
986 | get_packet(remcom_in_buffer); | |
987 | ||
988 | switch (remcom_in_buffer[0]) { | |
989 | case '?': /* gdbserial status */ | |
990 | gdb_cmd_status(ks); | |
991 | break; | |
992 | case 'g': /* return the value of the CPU registers */ | |
993 | gdb_cmd_getregs(ks); | |
994 | break; | |
995 | case 'G': /* set the value of the CPU registers - return OK */ | |
996 | gdb_cmd_setregs(ks); | |
997 | break; | |
998 | case 'm': /* mAA..AA,LLLL Read LLLL bytes at address AA..AA */ | |
999 | gdb_cmd_memread(ks); | |
1000 | break; | |
1001 | case 'M': /* MAA..AA,LLLL: Write LLLL bytes at address AA..AA */ | |
1002 | gdb_cmd_memwrite(ks); | |
1003 | break; | |
55751145 JW |
1004 | #if DBG_MAX_REG_NUM > 0 |
1005 | case 'p': /* pXX Return gdb register XX (in hex) */ | |
1006 | gdb_cmd_reg_get(ks); | |
1007 | break; | |
1008 | case 'P': /* PXX=aaaa Set gdb register XX to aaaa (in hex) */ | |
1009 | gdb_cmd_reg_set(ks); | |
1010 | break; | |
1011 | #endif /* DBG_MAX_REG_NUM > 0 */ | |
53197fc4 JW |
1012 | case 'X': /* XAA..AA,LLLL: Write LLLL bytes at address AA..AA */ |
1013 | gdb_cmd_binwrite(ks); | |
1014 | break; | |
1015 | /* kill or detach. KGDB should treat this like a | |
1016 | * continue. | |
1017 | */ | |
1018 | case 'D': /* Debugger detach */ | |
1019 | case 'k': /* Debugger detach via kill */ | |
1020 | gdb_cmd_detachkill(ks); | |
1021 | goto default_handle; | |
1022 | case 'R': /* Reboot */ | |
1023 | if (gdb_cmd_reboot(ks)) | |
1024 | goto default_handle; | |
1025 | break; | |
1026 | case 'q': /* query command */ | |
1027 | gdb_cmd_query(ks); | |
1028 | break; | |
1029 | case 'H': /* task related */ | |
1030 | gdb_cmd_task(ks); | |
1031 | break; | |
1032 | case 'T': /* Query thread status */ | |
1033 | gdb_cmd_thread(ks); | |
1034 | break; | |
1035 | case 'z': /* Break point remove */ | |
1036 | case 'Z': /* Break point set */ | |
1037 | gdb_cmd_break(ks); | |
1038 | break; | |
dcc78711 JW |
1039 | #ifdef CONFIG_KGDB_KDB |
1040 | case '3': /* Escape into back into kdb */ | |
1041 | if (remcom_in_buffer[1] == '\0') { | |
1042 | gdb_cmd_detachkill(ks); | |
1043 | return DBG_PASS_EVENT; | |
1044 | } | |
df561f66 | 1045 | fallthrough; |
1adee589 | 1046 | #endif |
53197fc4 JW |
1047 | case 'C': /* Exception passing */ |
1048 | tmp = gdb_cmd_exception_pass(ks); | |
1049 | if (tmp > 0) | |
1050 | goto default_handle; | |
1051 | if (tmp == 0) | |
1052 | break; | |
df561f66 | 1053 | fallthrough; /* on tmp < 0 */ |
53197fc4 JW |
1054 | case 'c': /* Continue packet */ |
1055 | case 's': /* Single step packet */ | |
1056 | if (kgdb_contthread && kgdb_contthread != current) { | |
1057 | /* Can't switch threads in kgdb */ | |
1058 | error_packet(remcom_out_buffer, -EINVAL); | |
1059 | break; | |
1060 | } | |
df561f66 | 1061 | fallthrough; /* to default processing */ |
53197fc4 JW |
1062 | default: |
1063 | default_handle: | |
1064 | error = kgdb_arch_handle_exception(ks->ex_vector, | |
1065 | ks->signo, | |
1066 | ks->err_code, | |
1067 | remcom_in_buffer, | |
1068 | remcom_out_buffer, | |
1069 | ks->linux_regs); | |
1070 | /* | |
1071 | * Leave cmd processing on error, detach, | |
1072 | * kill, continue, or single step. | |
1073 | */ | |
1074 | if (error >= 0 || remcom_in_buffer[0] == 'D' || | |
1075 | remcom_in_buffer[0] == 'k') { | |
1076 | error = 0; | |
1077 | goto kgdb_exit; | |
1078 | } | |
1079 | ||
1080 | } | |
1081 | ||
1082 | /* reply to the request */ | |
1083 | put_packet(remcom_out_buffer); | |
1084 | } | |
1085 | ||
1086 | kgdb_exit: | |
1087 | if (ks->pass_exception) | |
1088 | error = 1; | |
1089 | return error; | |
1090 | } | |
dcc78711 JW |
1091 | |
1092 | int gdbstub_state(struct kgdb_state *ks, char *cmd) | |
1093 | { | |
1094 | int error; | |
1095 | ||
1096 | switch (cmd[0]) { | |
1097 | case 'e': | |
1098 | error = kgdb_arch_handle_exception(ks->ex_vector, | |
1099 | ks->signo, | |
1100 | ks->err_code, | |
1101 | remcom_in_buffer, | |
1102 | remcom_out_buffer, | |
1103 | ks->linux_regs); | |
1104 | return error; | |
1105 | case 's': | |
1106 | case 'c': | |
4cc168ea | 1107 | strscpy(remcom_in_buffer, cmd, sizeof(remcom_in_buffer)); |
dcc78711 | 1108 | return 0; |
f679c498 | 1109 | case '$': |
4cc168ea | 1110 | strscpy(remcom_in_buffer, cmd, sizeof(remcom_in_buffer)); |
f679c498 JW |
1111 | gdbstub_use_prev_in_buf = strlen(remcom_in_buffer); |
1112 | gdbstub_prev_in_buf_pos = 0; | |
1113 | return 0; | |
dcc78711 JW |
1114 | } |
1115 | dbg_io_ops->write_char('+'); | |
1116 | put_packet(remcom_out_buffer); | |
1117 | return 0; | |
1118 | } | |
d57f078b DH |
1119 | |
1120 | /** | |
1121 | * gdbstub_exit - Send an exit message to GDB | |
1122 | * @status: The exit code to report. | |
1123 | */ | |
1124 | void gdbstub_exit(int status) | |
1125 | { | |
1126 | unsigned char checksum, ch, buffer[3]; | |
1127 | int loop; | |
1128 | ||
2366e047 JW |
1129 | if (!kgdb_connected) |
1130 | return; | |
1131 | kgdb_connected = 0; | |
1132 | ||
1133 | if (!dbg_io_ops || dbg_kdb_mode) | |
1134 | return; | |
1135 | ||
d57f078b DH |
1136 | buffer[0] = 'W'; |
1137 | buffer[1] = hex_asc_hi(status); | |
1138 | buffer[2] = hex_asc_lo(status); | |
1139 | ||
1140 | dbg_io_ops->write_char('$'); | |
1141 | checksum = 0; | |
1142 | ||
1143 | for (loop = 0; loop < 3; loop++) { | |
1144 | ch = buffer[loop]; | |
1145 | checksum += ch; | |
1146 | dbg_io_ops->write_char(ch); | |
1147 | } | |
1148 | ||
1149 | dbg_io_ops->write_char('#'); | |
1150 | dbg_io_ops->write_char(hex_asc_hi(checksum)); | |
1151 | dbg_io_ops->write_char(hex_asc_lo(checksum)); | |
1152 | ||
1153 | /* make sure the output is flushed, lest the bootloader clobber it */ | |
9fbe465e JK |
1154 | if (dbg_io_ops->flush) |
1155 | dbg_io_ops->flush(); | |
d57f078b | 1156 | } |