Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jwessel/linux-2.6-kgdb:
  kdb,kgdb: Allow arbitrary kgdb magic knock sequences
  kdb: Remove all references to DOING_KGDB2
  kdb,kgdb: Implement switch and pass buffer from kdb -> gdb
  kdb: cleanup unused variables missed in the original kdb merge

7 files changed, 53 insertions, 42 deletions

diff --git a/kernel/debug/gdbstub.c b/kernel/debug/gdbstub.c
index a11db956dd62..34872482315e 100644
--- a/kernel/debug/gdbstub.c
+++ b/kernel/debug/gdbstub.c
@@ -42,6 +42,8 @@
 /* Our I/O buffers. */
 static char                     remcom_in_buffer[BUFMAX];
 static char                     remcom_out_buffer[BUFMAX];
+static int                      gdbstub_use_prev_in_buf;
+static int                      gdbstub_prev_in_buf_pos;
 
 /* Storage for the registers, in GDB format. */
 static unsigned long            gdb_regs[(NUMREGBYTES +
@@ -58,6 +60,13 @@ static int gdbstub_read_wait(void)
         int ret = -1;
         int i;
 
+        if (unlikely(gdbstub_use_prev_in_buf)) {
+                if (gdbstub_prev_in_buf_pos < gdbstub_use_prev_in_buf)
+                        return remcom_in_buffer[gdbstub_prev_in_buf_pos++];
+                else
+                        gdbstub_use_prev_in_buf = 0;
+        }
+
         /* poll any additional I/O interfaces that are defined */
         while (ret < 0)
                 for (i = 0; kdb_poll_funcs[i] != NULL; i++) {
@@ -109,7 +118,6 @@ static void get_packet(char *buffer)
                         buffer[count] = ch;
                         count = count + 1;
                 }
-                buffer[count] = 0;
 
                 if (ch == '#') {
                         xmitcsum = hex_to_bin(gdbstub_read_wait()) << 4;
@@ -124,6 +132,7 @@ static void get_packet(char *buffer)
                         if (dbg_io_ops->flush)
                                 dbg_io_ops->flush();
                 }
+                buffer[count] = 0;
         } while (checksum != xmitcsum);
 }
 
@@ -1082,12 +1091,11 @@ int gdbstub_state(struct kgdb_state *ks, char *cmd)
         case 'c':
                 strcpy(remcom_in_buffer, cmd);
                 return 0;
-        case '?':
-                gdb_cmd_status(ks);
-                break;
-        case '\0':
-                strcpy(remcom_out_buffer, "");
-                break;
+        case '$':
+                strcpy(remcom_in_buffer, cmd);
+                gdbstub_use_prev_in_buf = strlen(remcom_in_buffer);
+                gdbstub_prev_in_buf_pos = 0;
+                return 0;
         }
         dbg_io_ops->write_char('+');
         put_packet(remcom_out_buffer);
diff --git a/kernel/debug/kdb/kdb_bt.c b/kernel/debug/kdb/kdb_bt.c
index 2f62fe85f16a..7179eac7b41c 100644
--- a/kernel/debug/kdb/kdb_bt.c
+++ b/kernel/debug/kdb/kdb_bt.c
@@ -112,9 +112,8 @@ kdb_bt(int argc, const char **argv)
         unsigned long addr;
         long offset;
 
-        kdbgetintenv("BTARGS", &argcount);      /* Arguments to print */
-        kdbgetintenv("BTAPROMPT", &btaprompt);  /* Prompt after each
-                                                 * proc in bta */
+        /* Prompt after each proc in bta */
+        kdbgetintenv("BTAPROMPT", &btaprompt);
 
         if (strcmp(argv[0], "bta") == 0) {
                 struct task_struct *g, *p;
diff --git a/kernel/debug/kdb/kdb_cmds b/kernel/debug/kdb/kdb_cmds
index 56c88e4db309..9834ad303ab6 100644
--- a/kernel/debug/kdb/kdb_cmds
+++ b/kernel/debug/kdb/kdb_cmds
@@ -18,16 +18,12 @@ defcmd dumpcommon "" "Common kdb debugging"
 endefcmd
 
 defcmd dumpall "" "First line debugging"
-  set BTSYMARG 1
-  set BTARGS 9
   pid R
   -dumpcommon
   -bta
 endefcmd
 
 defcmd dumpcpu "" "Same as dumpall but only tasks on cpus"
-  set BTSYMARG 1
-  set BTARGS 9
   pid R
   -dumpcommon
   -btc
diff --git a/kernel/debug/kdb/kdb_debugger.c b/kernel/debug/kdb/kdb_debugger.c
index dd0b1b7dd02c..d9ca9aa481ec 100644
--- a/kernel/debug/kdb/kdb_debugger.c
+++ b/kernel/debug/kdb/kdb_debugger.c
@@ -30,6 +30,8 @@ EXPORT_SYMBOL_GPL(kdb_poll_funcs);
 int kdb_poll_idx = 1;
 EXPORT_SYMBOL_GPL(kdb_poll_idx);
 
+static struct kgdb_state *kdb_ks;
+
 int kdb_stub(struct kgdb_state *ks)
 {
         int error = 0;
@@ -39,6 +41,7 @@ int kdb_stub(struct kgdb_state *ks)
         kdb_dbtrap_t db_result = KDB_DB_NOBPT;
         int i;
 
+        kdb_ks = ks;
         if (KDB_STATE(REENTRY)) {
                 reason = KDB_REASON_SWITCH;
                 KDB_STATE_CLEAR(REENTRY);
@@ -123,20 +126,8 @@ int kdb_stub(struct kgdb_state *ks)
         KDB_STATE_CLEAR(PAGER);
         kdbnearsym_cleanup();
         if (error == KDB_CMD_KGDB) {
-                if (KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)) {
-        /*
-         * This inteface glue which allows kdb to transition in into
-         * the gdb stub.  In order to do this the '?' or '' gdb serial
-         * packet response is processed here.  And then control is
-         * passed to the gdbstub.
-         */
-                        if (KDB_STATE(DOING_KGDB))
-                                gdbstub_state(ks, "?");
-                        else
-                                gdbstub_state(ks, "");
+                if (KDB_STATE(DOING_KGDB))
                         KDB_STATE_CLEAR(DOING_KGDB);
-                        KDB_STATE_CLEAR(DOING_KGDB2);
-                }
                 return DBG_PASS_EVENT;
         }
         kdb_bp_install(ks->linux_regs);
@@ -166,3 +157,7 @@ int kdb_stub(struct kgdb_state *ks)
         return kgdb_info[ks->cpu].ret_state;
 }
 
+void kdb_gdb_state_pass(char *buf)
+{
+        gdbstub_state(kdb_ks, buf);
+}
diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 96fdaac46a80..4802eb5840e1 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -31,15 +31,21 @@ char kdb_prompt_str[CMD_BUFLEN];
 
 int kdb_trap_printk;
 
-static void kgdb_transition_check(char *buffer)
+static int kgdb_transition_check(char *buffer)
 {
-        int slen = strlen(buffer);
-        if (strncmp(buffer, "$?#3f", slen) != 0 &&
-            strncmp(buffer, "$qSupported#37", slen) != 0 &&
-            strncmp(buffer, "+$qSupported#37", slen) != 0) {
+        if (buffer[0] != '+' && buffer[0] != '$') {
                 KDB_STATE_SET(KGDB_TRANS);
                 kdb_printf("%s", buffer);
+        } else {
+                int slen = strlen(buffer);
+                if (slen > 3 && buffer[slen - 3] == '#') {
+                        kdb_gdb_state_pass(buffer);
+                        strcpy(buffer, "kgdb");
+                        KDB_STATE_SET(DOING_KGDB);
+                        return 1;
+                }
         }
+        return 0;
 }
 
 static int kdb_read_get_key(char *buffer, size_t bufsize)
@@ -251,6 +257,10 @@ poll_again:
         case 13: /* enter */
                 *lastchar++ = '\n';
                 *lastchar++ = '\0';
+                if (!KDB_STATE(KGDB_TRANS)) {
+                        KDB_STATE_SET(KGDB_TRANS);
+                        kdb_printf("%s", buffer);
+                }
                 kdb_printf("\n");
                 return buffer;
         case 4: /* Del */
@@ -382,22 +392,26 @@ poll_again:
                                  * printed characters if we think that
                                  * kgdb is connecting, until the check
                                  * fails */
-                                if (!KDB_STATE(KGDB_TRANS))
-                                        kgdb_transition_check(buffer);
-                                else
+                                if (!KDB_STATE(KGDB_TRANS)) {
+                                        if (kgdb_transition_check(buffer))
+                                                return buffer;
+                                } else {
                                         kdb_printf("%c", key);
+                                }
                         }
                         /* Special escape to kgdb */
                         if (lastchar - buffer >= 5 &&
                             strcmp(lastchar - 5, "$?#3f") == 0) {
+                                kdb_gdb_state_pass(lastchar - 5);
                                 strcpy(buffer, "kgdb");
                                 KDB_STATE_SET(DOING_KGDB);
                                 return buffer;
                         }
-                        if (lastchar - buffer >= 14 &&
-                            strcmp(lastchar - 14, "$qSupported#37") == 0) {
+                        if (lastchar - buffer >= 11 &&
+                            strcmp(lastchar - 11, "$qSupported") == 0) {
+                                kdb_gdb_state_pass(lastchar - 11);
                                 strcpy(buffer, "kgdb");
-                                KDB_STATE_SET(DOING_KGDB2);
+                                KDB_STATE_SET(DOING_KGDB);
                                 return buffer;
                         }
                 }
diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c
index be14779bcef6..63786e71a3cd 100644
--- a/kernel/debug/kdb/kdb_main.c
+++ b/kernel/debug/kdb/kdb_main.c
@@ -145,7 +145,6 @@ static char *__env[] = {
 #endif
  "RADIX=16",
  "MDCOUNT=8",                   /* lines of md output */
- "BTARGS=9",                    /* 9 possible args in bt */
  KDB_PLATFORM_ENV,
  "DTABCOUNT=30",
  "NOSECT=1",
@@ -172,6 +171,7 @@ static char *__env[] = {
  (char *)0,
  (char *)0,
  (char *)0,
+ (char *)0,
 };
 
 static const int __nenv = (sizeof(__env) / sizeof(char *));
@@ -1386,7 +1386,7 @@ int kdb_main_loop(kdb_reason_t reason, kdb_reason_t reason2, int error,
                 }
 
                 if (result == KDB_CMD_KGDB) {
-                        if (!(KDB_STATE(DOING_KGDB) || KDB_STATE(DOING_KGDB2)))
+                        if (!KDB_STATE(DOING_KGDB))
                                 kdb_printf("Entering please attach debugger "
                                            "or use $D#44+ or $3#33\n");
                         break;
diff --git a/kernel/debug/kdb/kdb_private.h b/kernel/debug/kdb/kdb_private.h
index 35d69ed1dfb5..e381d105b40b 100644
--- a/kernel/debug/kdb/kdb_private.h
+++ b/kernel/debug/kdb/kdb_private.h
@@ -21,7 +21,6 @@
 #define KDB_CMD_SS      (-1003)
 #define KDB_CMD_SSB     (-1004)
 #define KDB_CMD_KGDB (-1005)
-#define KDB_CMD_KGDB2 (-1006)
 
 /* Internal debug flags */
 #define KDB_DEBUG_FLAG_BP       0x0002  /* Breakpoint subsystem debug */
@@ -146,7 +145,6 @@ extern int kdb_state;
                                                  * keyboard on this cpu */
 #define KDB_STATE_KEXEC         0x00040000      /* kexec issued */
 #define KDB_STATE_DOING_KGDB    0x00080000      /* kgdb enter now issued */
-#define KDB_STATE_DOING_KGDB2   0x00100000      /* kgdb enter now issued */
 #define KDB_STATE_KGDB_TRANS    0x00200000      /* Transition to kgdb */
 #define KDB_STATE_ARCH          0xff000000      /* Reserved for arch
                                                  * specific use */
@@ -218,6 +216,7 @@ extern void kdb_print_nameval(const char *name, unsigned long val);
 extern void kdb_send_sig_info(struct task_struct *p, struct siginfo *info);
 extern void kdb_meminfo_proc_show(void);
 extern char *kdb_getstr(char *, size_t, char *);
+extern void kdb_gdb_state_pass(char *buf);
 
 /* Defines for kdb_symbol_print */
 #define KDB_SP_SPACEB   0x0001          /* Space before string */