1 files changed, 115 insertions, 45 deletions

diff --git a/drivers/misc/kgdbts.c b/drivers/misc/kgdbts.c
index 3f7ad83ed74..3aa9a969b37 100644
--- a/drivers/misc/kgdbts.c
+++ b/drivers/misc/kgdbts.c
@@ -134,12 +134,17 @@ static int force_hwbrks;
 static int hwbreaks_ok;
 static int hw_break_val;
 static int hw_break_val2;
+static int cont_instead_of_sstep;
+static unsigned long cont_thread_id;
+static unsigned long sstep_thread_id;
 #if defined(CONFIG_ARM) || defined(CONFIG_MIPS) || defined(CONFIG_SPARC)
 static int arch_needs_sstep_emulation = 1;
 #else
 static int arch_needs_sstep_emulation;
 #endif
+static unsigned long cont_addr;
 static unsigned long sstep_addr;
+static int restart_from_top_after_write;
 static int sstep_state;
 
 /* Storage for the registers, in GDB format. */
@@ -187,7 +192,8 @@ static int kgdbts_unreg_thread(void *ptr)
          */
         while (!final_ack)
                 msleep_interruptible(1500);
-
+        /* Pause for any other threads to exit after final ack. */
+        msleep_interruptible(1000);
         if (configured)
                 kgdb_unregister_io_module(&kgdbts_io_ops);
         configured = 0;
@@ -211,7 +217,7 @@ static unsigned long lookup_addr(char *arg)
         if (!strcmp(arg, "kgdbts_break_test"))
                 addr = (unsigned long)kgdbts_break_test;
         else if (!strcmp(arg, "sys_open"))
-                addr = (unsigned long)sys_open;
+                addr = (unsigned long)do_sys_open;
         else if (!strcmp(arg, "do_fork"))
                 addr = (unsigned long)do_fork;
         else if (!strcmp(arg, "hw_break_val"))
@@ -283,6 +289,16 @@ static void hw_break_val_write(void)
         hw_break_val++;
 }
 
+static int get_thread_id_continue(char *put_str, char *arg)
+{
+        char *ptr = &put_str[11];
+
+        if (put_str[1] != 'T' || put_str[2] != '0')
+                return 1;
+        kgdb_hex2long(&ptr, &cont_thread_id);
+        return 0;
+}
+
 static int check_and_rewind_pc(char *put_str, char *arg)
 {
         unsigned long addr = lookup_addr(arg);
@@ -299,13 +315,21 @@ static int check_and_rewind_pc(char *put_str, char *arg)
         if (addr + BREAK_INSTR_SIZE == ip)
                 offset = -BREAK_INSTR_SIZE;
 #endif
-        if (strcmp(arg, "silent") && ip + offset != addr) {
+
+        if (arch_needs_sstep_emulation && sstep_addr &&
+            ip + offset == sstep_addr &&
+            ((!strcmp(arg, "sys_open") || !strcmp(arg, "do_fork")))) {
+                /* This is special case for emulated single step */
+                v2printk("Emul: rewind hit single step bp\n");
+                restart_from_top_after_write = 1;
+        } else if (strcmp(arg, "silent") && ip + offset != addr) {
                 eprintk("kgdbts: BP mismatch %lx expected %lx\n",
                            ip + offset, addr);
                 return 1;
         }
         /* Readjust the instruction pointer if needed */
         ip += offset;
+        cont_addr = ip;
 #ifdef GDB_ADJUSTS_BREAK_OFFSET
         instruction_pointer_set(&kgdbts_regs, ip);
 #endif
@@ -315,6 +339,8 @@ static int check_and_rewind_pc(char *put_str, char *arg)
 static int check_single_step(char *put_str, char *arg)
 {
         unsigned long addr = lookup_addr(arg);
+        static int matched_id;
+
         /*
          * From an arch indepent point of view the instruction pointer
          * should be on a different instruction
@@ -324,6 +350,29 @@ static int check_single_step(char *put_str, char *arg)
         gdb_regs_to_pt_regs(kgdbts_gdb_regs, &kgdbts_regs);
         v2printk("Singlestep stopped at IP: %lx\n",
                    instruction_pointer(&kgdbts_regs));
+
+        if (sstep_thread_id != cont_thread_id) {
+                /*
+                 * Ensure we stopped in the same thread id as before, else the
+                 * debugger should continue until the original thread that was
+                 * single stepped is scheduled again, emulating gdb's behavior.
+                 */
+                v2printk("ThrID does not match: %lx\n", cont_thread_id);
+                if (arch_needs_sstep_emulation) {
+                        if (matched_id &&
+                            instruction_pointer(&kgdbts_regs) != addr)
+                                goto continue_test;
+                        matched_id++;
+                        ts.idx -= 2;
+                        sstep_state = 0;
+                        return 0;
+                }
+                cont_instead_of_sstep = 1;
+                ts.idx -= 4;
+                return 0;
+        }
+continue_test:
+        matched_id = 0;
         if (instruction_pointer(&kgdbts_regs) == addr) {
                 eprintk("kgdbts: SingleStep failed at %lx\n",
                            instruction_pointer(&kgdbts_regs));
@@ -365,10 +414,40 @@ static int got_break(char *put_str, char *arg)
         return 1;
 }
 
+static void get_cont_catch(char *arg)
+{
+        /* Always send detach because the test is completed at this point */
+        fill_get_buf("D");
+}
+
+static int put_cont_catch(char *put_str, char *arg)
+{
+        /* This is at the end of the test and we catch any and all input */
+        v2printk("kgdbts: cleanup task: %lx\n", sstep_thread_id);
+        ts.idx--;
+        return 0;
+}
+
+static int emul_reset(char *put_str, char *arg)
+{
+        if (strncmp(put_str, "$OK", 3))
+                return 1;
+        if (restart_from_top_after_write) {
+                restart_from_top_after_write = 0;
+                ts.idx = -1;
+        }
+        return 0;
+}
+
 static void emul_sstep_get(char *arg)
 {
         if (!arch_needs_sstep_emulation) {
-                fill_get_buf(arg);
+                if (cont_instead_of_sstep) {
+                        cont_instead_of_sstep = 0;
+                        fill_get_buf("c");
+                } else {
+                        fill_get_buf(arg);
+                }
                 return;
         }
         switch (sstep_state) {
@@ -398,9 +477,11 @@ static void emul_sstep_get(char *arg)
 static int emul_sstep_put(char *put_str, char *arg)
 {
         if (!arch_needs_sstep_emulation) {
-                if (!strncmp(put_str+1, arg, 2))
-                        return 0;
-                return 1;
+                char *ptr = &put_str[11];
+                if (put_str[1] != 'T' || put_str[2] != '0')
+                        return 1;
+                kgdb_hex2long(&ptr, &sstep_thread_id);
+                return 0;
         }
         switch (sstep_state) {
         case 1:
@@ -411,8 +492,7 @@ static int emul_sstep_put(char *put_str, char *arg)
                 v2printk("Stopped at IP: %lx\n",
                          instruction_pointer(&kgdbts_regs));
                 /* Want to stop at IP + break instruction size by default */
-                sstep_addr = instruction_pointer(&kgdbts_regs) +
-                        BREAK_INSTR_SIZE;
+                sstep_addr = cont_addr + BREAK_INSTR_SIZE;
                 break;
         case 2:
                 if (strncmp(put_str, "$OK", 3)) {
@@ -424,6 +504,9 @@ static int emul_sstep_put(char *put_str, char *arg)
                 if (strncmp(put_str, "$T0", 3)) {
                         eprintk("kgdbts: failed continue sstep\n");
                         return 1;
+                } else {
+                        char *ptr = &put_str[11];
+                        kgdb_hex2long(&ptr, &sstep_thread_id);
                 }
                 break;
         case 4:
@@ -502,10 +585,10 @@ static struct test_struct bad_read_test[] = {
 static struct test_struct singlestep_break_test[] = {
         { "?", "S0*" }, /* Clear break points */
         { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
-        { "c", "T0*", }, /* Continue */
+        { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
+        { "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
         { "g", "kgdbts_break_test", NULL, check_and_rewind_pc },
         { "write", "OK", write_regs }, /* Write registers */
-        { "kgdbts_break_test", "OK", sw_rem_break }, /*remove breakpoint */
         { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
         { "g", "kgdbts_break_test", NULL, check_single_step },
         { "kgdbts_break_test", "OK", sw_break, }, /* set sw breakpoint */
@@ -523,16 +606,16 @@ static struct test_struct singlestep_break_test[] = {
 static struct test_struct do_fork_test[] = {
         { "?", "S0*" }, /* Clear break points */
         { "do_fork", "OK", sw_break, }, /* set sw breakpoint */
-        { "c", "T0*", }, /* Continue */
-        { "g", "do_fork", NULL, check_and_rewind_pc }, /* check location */
-        { "write", "OK", write_regs }, /* Write registers */
+        { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
         { "do_fork", "OK", sw_rem_break }, /*remove breakpoint */
+        { "g", "do_fork", NULL, check_and_rewind_pc }, /* check location */
+        { "write", "OK", write_regs, emul_reset }, /* Write registers */
         { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
         { "g", "do_fork", NULL, check_single_step },
         { "do_fork", "OK", sw_break, }, /* set sw breakpoint */
         { "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
         { "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
-        { "", "" },
+        { "", "", get_cont_catch, put_cont_catch },
 };
 
 /* Test for hitting a breakpoint at sys_open for what ever the number
@@ -541,16 +624,16 @@ static struct test_struct do_fork_test[] = {
 static struct test_struct sys_open_test[] = {
         { "?", "S0*" }, /* Clear break points */
         { "sys_open", "OK", sw_break, }, /* set sw breakpoint */
-        { "c", "T0*", }, /* Continue */
-        { "g", "sys_open", NULL, check_and_rewind_pc }, /* check location */
-        { "write", "OK", write_regs }, /* Write registers */
+        { "c", "T0*", NULL, get_thread_id_continue }, /* Continue */
         { "sys_open", "OK", sw_rem_break }, /*remove breakpoint */
+        { "g", "sys_open", NULL, check_and_rewind_pc }, /* check location */
+        { "write", "OK", write_regs, emul_reset }, /* Write registers */
         { "s", "T0*", emul_sstep_get, emul_sstep_put }, /* Single step */
         { "g", "sys_open", NULL, check_single_step },
         { "sys_open", "OK", sw_break, }, /* set sw breakpoint */
         { "7", "T0*", skip_back_repeat_test }, /* Loop based on repeat_test */
         { "D", "OK", NULL, final_ack_set }, /* detach and unregister I/O */
-        { "", "" },
+        { "", "", get_cont_catch, put_cont_catch },
 };
 
 /*
@@ -693,8 +776,8 @@ static int run_simple_test(int is_get_char, int chr)
         /* This callback is a put char which is when kgdb sends data to
          * this I/O module.
          */
-        if (ts.tst[ts.idx].get[0] == '\0' &&
-                ts.tst[ts.idx].put[0] == '\0') {
+        if (ts.tst[ts.idx].get[0] == '\0' && ts.tst[ts.idx].put[0] == '\0' &&
+            !ts.tst[ts.idx].get_handler) {
                 eprintk("kgdbts: ERROR: beyond end of test on"
                            " '%s' line %i\n", ts.name, ts.idx);
                 return 0;
@@ -907,6 +990,17 @@ static void kgdbts_run_tests(void)
         if (ptr)
                 sstep_test = simple_strtol(ptr+1, NULL, 10);
 
+        /* All HW break point tests */
+        if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
+                hwbreaks_ok = 1;
+                v1printk("kgdbts:RUN hw breakpoint test\n");
+                run_breakpoint_test(1);
+                v1printk("kgdbts:RUN hw write breakpoint test\n");
+                run_hw_break_test(1);
+                v1printk("kgdbts:RUN access write breakpoint test\n");
+                run_hw_break_test(0);
+        }
+
         /* required internal KGDB tests */
         v1printk("kgdbts:RUN plant and detach test\n");
         run_plant_and_detach_test(0);
@@ -924,35 +1018,11 @@ static void kgdbts_run_tests(void)
 
         /* ===Optional tests=== */
 
-        /* All HW break point tests */
-        if (arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT) {
-                hwbreaks_ok = 1;
-                v1printk("kgdbts:RUN hw breakpoint test\n");
-                run_breakpoint_test(1);
-                v1printk("kgdbts:RUN hw write breakpoint test\n");
-                run_hw_break_test(1);
-                v1printk("kgdbts:RUN access write breakpoint test\n");
-                run_hw_break_test(0);
-        }
-
         if (nmi_sleep) {
                 v1printk("kgdbts:RUN NMI sleep %i seconds test\n", nmi_sleep);
                 run_nmi_sleep_test(nmi_sleep);
         }
 
-#ifdef CONFIG_DEBUG_RODATA
-        /* Until there is an api to write to read-only text segments, use
-         * HW breakpoints for the remainder of any tests, else print a
-         * failure message if hw breakpoints do not work.
-         */
-        if (!(arch_kgdb_ops.flags & KGDB_HW_BREAKPOINT && hwbreaks_ok)) {
-                eprintk("kgdbts: HW breakpoints do not work,"
-                        "skipping remaining tests\n");
-                return;
-        }
-        force_hwbrks = 1;
-#endif /* CONFIG_DEBUG_RODATA */
-
         /* If the do_fork test is run it will be the last test that is
          * executed because a kernel thread will be spawned at the very
          * end to unregister the debug hooks.