2 * Copyright (C) 2011 Red Hat, Inc., Frederic Weisbecker <fweisbec@redhat.com>
4 * Licensed under the terms of the GNU GPL License version 2
6 * Selftests for breakpoints (and more generally the do_debug() path) in x86.
10 #include <sys/ptrace.h>
17 #include <sys/types.h>
21 /* Breakpoint access modes */
28 static pid_t child_pid;
31 * Ensures the child and parent are always "talking" about
32 * the same test sequence. (ie: that we haven't forgotten
33 * to call check_trapped() somewhere).
37 static void set_breakpoint_addr(void *addr, int n)
41 ret = ptrace(PTRACE_POKEUSER, child_pid,
42 offsetof(struct user, u_debugreg[n]), addr);
44 perror("Can't set breakpoint addr\n");
49 static void toggle_breakpoint(int n, int type, int len,
50 int local, int global, int set)
55 unsigned long vdr7, dr7;
84 dr7 = ptrace(PTRACE_PEEKUSER, child_pid,
85 offsetof(struct user, u_debugreg[7]), 0);
87 vdr7 = (xlen | xtype) << 16;
104 ret = ptrace(PTRACE_POKEUSER, child_pid,
105 offsetof(struct user, u_debugreg[7]), dr7);
107 perror("Can't set dr7");
112 /* Dummy variables to test read/write accesses */
113 static unsigned long long dummy_var[4];
115 /* Dummy functions to test execution accesses */
116 static void dummy_func(void) { }
117 static void dummy_func1(void) { }
118 static void dummy_func2(void) { }
119 static void dummy_func3(void) { }
121 static void (*dummy_funcs[])(void) = {
130 static void check_trapped(void)
133 * If we haven't trapped, wake up the parent
134 * so that it notices the failure.
137 kill(getpid(), SIGUSR1);
143 static void write_var(int len)
145 char *pcval; short *psval; int *pival; long long *plval;
148 for (i = 0; i < 4; i++) {
151 pcval = (char *)&dummy_var[i];
155 psval = (short *)&dummy_var[i];
159 pival = (int *)&dummy_var[i];
163 plval = (long long *)&dummy_var[i];
164 *plval = 0xffffffffffffffffLL;
171 static void read_var(int len)
173 char cval; short sval; int ival; long long lval;
176 for (i = 0; i < 4; i++) {
179 cval = *(char *)&dummy_var[i];
182 sval = *(short *)&dummy_var[i];
185 ival = *(int *)&dummy_var[i];
188 lval = *(long long *)&dummy_var[i];
196 * Do the r/w/x accesses to trigger the breakpoints. And run
199 static void trigger_tests(void)
201 int len, local, global, i;
205 ret = ptrace(PTRACE_TRACEME, 0, NULL, 0);
207 perror("Can't be traced?\n");
211 /* Wake up father so that it sets up the first test */
212 kill(getpid(), SIGUSR1);
214 /* Test instruction breakpoints */
215 for (local = 0; local < 2; local++) {
216 for (global = 0; global < 2; global++) {
217 if (!local && !global)
220 for (i = 0; i < 4; i++) {
227 /* Test write watchpoints */
228 for (len = 1; len <= sizeof(long); len <<= 1) {
229 for (local = 0; local < 2; local++) {
230 for (global = 0; global < 2; global++) {
231 if (!local && !global)
238 /* Test read/write watchpoints (on read accesses) */
239 for (len = 1; len <= sizeof(long); len <<= 1) {
240 for (local = 0; local < 2; local++) {
241 for (global = 0; global < 2; global++) {
242 if (!local && !global)
257 kill(getpid(), SIGUSR1);
260 static void check_success(const char *msg)
266 /* Wait for the child to SIGTRAP */
271 if (WSTOPSIG(status) == SIGTRAP) {
272 child_nr_tests = ptrace(PTRACE_PEEKDATA, child_pid,
274 if (child_nr_tests == nr_tests)
276 if (ptrace(PTRACE_POKEDATA, child_pid, &trapped, 1)) {
277 perror("Can't poke\n");
284 printf("%s [%s]\n", msg, msg2);
287 static void launch_instruction_breakpoints(char *buf, int local, int global)
291 for (i = 0; i < 4; i++) {
292 set_breakpoint_addr(dummy_funcs[i], i);
293 toggle_breakpoint(i, BP_X, 1, local, global, 1);
294 ptrace(PTRACE_CONT, child_pid, NULL, 0);
295 sprintf(buf, "Test breakpoint %d with local: %d global: %d",
298 toggle_breakpoint(i, BP_X, 1, local, global, 0);
302 static void launch_watchpoints(char *buf, int mode, int len,
303 int local, int global)
305 const char *mode_str;
313 for (i = 0; i < 4; i++) {
314 set_breakpoint_addr(&dummy_var[i], i);
315 toggle_breakpoint(i, mode, len, local, global, 1);
316 ptrace(PTRACE_CONT, child_pid, NULL, 0);
317 sprintf(buf, "Test %s watchpoint %d with len: %d local: "
318 "%d global: %d", mode_str, i, len, local, global);
320 toggle_breakpoint(i, mode, len, local, global, 0);
324 /* Set the breakpoints and check the child successfully trigger them */
325 static void launch_tests(void)
328 int len, local, global, i;
330 /* Instruction breakpoints */
331 for (local = 0; local < 2; local++) {
332 for (global = 0; global < 2; global++) {
333 if (!local && !global)
335 launch_instruction_breakpoints(buf, local, global);
339 /* Write watchpoint */
340 for (len = 1; len <= sizeof(long); len <<= 1) {
341 for (local = 0; local < 2; local++) {
342 for (global = 0; global < 2; global++) {
343 if (!local && !global)
345 launch_watchpoints(buf, BP_W, len,
351 /* Read-Write watchpoint */
352 for (len = 1; len <= sizeof(long); len <<= 1) {
353 for (local = 0; local < 2; local++) {
354 for (global = 0; global < 2; global++) {
355 if (!local && !global)
357 launch_watchpoints(buf, BP_RW, len,
364 ptrace(PTRACE_CONT, child_pid, NULL, 0);
365 check_success("Test icebp");
368 ptrace(PTRACE_CONT, child_pid, NULL, 0);
369 check_success("Test int 3 trap");
371 ptrace(PTRACE_CONT, child_pid, NULL, 0);
374 int main(int argc, char **argv)