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-rw-r--r--arch/um/kernel/tt/gdb.c278
1 files changed, 278 insertions, 0 deletions
diff --git a/arch/um/kernel/tt/gdb.c b/arch/um/kernel/tt/gdb.c
new file mode 100644
index 0000000..19a0ad7
--- /dev/null
+++ b/arch/um/kernel/tt/gdb.c
@@ -0,0 +1,278 @@
+/*
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <string.h>
+#include <signal.h>
+#include <sys/types.h>
+#include "ptrace_user.h"
+#include "uml-config.h"
+#include "kern_constants.h"
+#include "chan_user.h"
+#include "init.h"
+#include "user.h"
+#include "debug.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "tt.h"
+#include "sysdep/thread.h"
+
+extern int debugger_pid;
+extern int debugger_fd;
+extern int debugger_parent;
+
+int detach(int pid, int sig)
+{
+ return(ptrace(PTRACE_DETACH, pid, 0, sig));
+}
+
+int attach(int pid)
+{
+ int err;
+
+ err = ptrace(PTRACE_ATTACH, pid, 0, 0);
+ if(err < 0) return(-errno);
+ else return(err);
+}
+
+int cont(int pid)
+{
+ return(ptrace(PTRACE_CONT, pid, 0, 0));
+}
+
+#ifdef UML_CONFIG_PT_PROXY
+
+int debugger_signal(int status, pid_t pid)
+{
+ return(debugger_proxy(status, pid));
+}
+
+void child_signal(pid_t pid, int status)
+{
+ child_proxy(pid, status);
+}
+
+static void gdb_announce(char *dev_name, int dev)
+{
+ printf("gdb assigned device '%s'\n", dev_name);
+}
+
+static struct chan_opts opts = {
+ .announce = gdb_announce,
+ .xterm_title = "UML kernel debugger",
+ .raw = 0,
+ .tramp_stack = 0,
+ .in_kernel = 0,
+};
+
+/* Accessed by the tracing thread, which automatically serializes access */
+static void *xterm_data;
+static int xterm_fd;
+
+extern void *xterm_init(char *, int, struct chan_opts *);
+extern int xterm_open(int, int, int, void *, char **);
+extern void xterm_close(int, void *);
+
+int open_gdb_chan(void)
+{
+ char stack[UM_KERN_PAGE_SIZE], *dummy;
+
+ opts.tramp_stack = (unsigned long) stack;
+ xterm_data = xterm_init("", 0, &opts);
+ xterm_fd = xterm_open(1, 1, 1, xterm_data, &dummy);
+ return(xterm_fd);
+}
+
+static void exit_debugger_cb(void *unused)
+{
+ if(debugger_pid != -1){
+ if(gdb_pid != -1){
+ fake_child_exit();
+ gdb_pid = -1;
+ }
+ else kill_child_dead(debugger_pid);
+ debugger_pid = -1;
+ if(debugger_parent != -1)
+ detach(debugger_parent, SIGINT);
+ }
+ if(xterm_data != NULL) xterm_close(xterm_fd, xterm_data);
+}
+
+static void exit_debugger(void)
+{
+ initial_thread_cb(exit_debugger_cb, NULL);
+}
+
+__uml_exitcall(exit_debugger);
+
+struct gdb_data {
+ char *str;
+ int err;
+};
+
+static void config_gdb_cb(void *arg)
+{
+ struct gdb_data *data = arg;
+ void *task;
+ int pid;
+
+ data->err = -1;
+ if(debugger_pid != -1) exit_debugger_cb(NULL);
+ if(!strncmp(data->str, "pid,", strlen("pid,"))){
+ data->str += strlen("pid,");
+ pid = strtoul(data->str, NULL, 0);
+ task = cpu_tasks[0].task;
+ debugger_pid = attach_debugger(TASK_EXTERN_PID(task), pid, 0);
+ if(debugger_pid != -1){
+ data->err = 0;
+ gdb_pid = pid;
+ }
+ return;
+ }
+ data->err = 0;
+ debugger_pid = start_debugger(linux_prog, 0, 0, &debugger_fd);
+ init_proxy(debugger_pid, 0, 0);
+}
+
+int gdb_config(char *str)
+{
+ struct gdb_data data;
+
+ if(*str++ != '=') return(-1);
+ data.str = str;
+ initial_thread_cb(config_gdb_cb, &data);
+ return(data.err);
+}
+
+void remove_gdb_cb(void *unused)
+{
+ exit_debugger_cb(NULL);
+}
+
+int gdb_remove(char *unused)
+{
+ initial_thread_cb(remove_gdb_cb, NULL);
+ return(0);
+}
+
+void signal_usr1(int sig)
+{
+ if(debugger_pid != -1){
+ printf("The debugger is already running\n");
+ return;
+ }
+ debugger_pid = start_debugger(linux_prog, 0, 0, &debugger_fd);
+ init_proxy(debugger_pid, 0, 0);
+}
+
+int init_ptrace_proxy(int idle_pid, int startup, int stop)
+{
+ int pid, status;
+
+ pid = start_debugger(linux_prog, startup, stop, &debugger_fd);
+ status = wait_for_stop(idle_pid, SIGSTOP, PTRACE_CONT, NULL);
+ if(pid < 0){
+ cont(idle_pid);
+ return(-1);
+ }
+ init_proxy(pid, 1, status);
+ return(pid);
+}
+
+int attach_debugger(int idle_pid, int pid, int stop)
+{
+ int status = 0, err;
+
+ err = attach(pid);
+ if(err < 0){
+ printf("Failed to attach pid %d, errno = %d\n", pid, -err);
+ return(-1);
+ }
+ if(stop) status = wait_for_stop(idle_pid, SIGSTOP, PTRACE_CONT, NULL);
+ init_proxy(pid, 1, status);
+ return(pid);
+}
+
+#ifdef notdef /* Put this back in when it does something useful */
+static int __init uml_gdb_init_setup(char *line, int *add)
+{
+ gdb_init = uml_strdup(line);
+ return 0;
+}
+
+__uml_setup("gdb=", uml_gdb_init_setup,
+"gdb=<channel description>\n\n"
+);
+#endif
+
+static int __init uml_gdb_pid_setup(char *line, int *add)
+{
+ gdb_pid = strtoul(line, NULL, 0);
+ *add = 0;
+ return 0;
+}
+
+__uml_setup("gdb-pid=", uml_gdb_pid_setup,
+"gdb-pid=<pid>\n"
+" gdb-pid is used to attach an external debugger to UML. This may be\n"
+" an already-running gdb or a debugger-like process like strace.\n\n"
+);
+
+#else
+
+int debugger_signal(int status, pid_t pid){ return(0); }
+void child_signal(pid_t pid, int status){ }
+int init_ptrace_proxy(int idle_pid, int startup, int stop)
+{
+ printf("debug requested when CONFIG_PT_PROXY is off\n");
+ kill_child_dead(idle_pid);
+ exit(1);
+}
+
+void signal_usr1(int sig)
+{
+ printf("debug requested when CONFIG_PT_PROXY is off\n");
+}
+
+int attach_debugger(int idle_pid, int pid, int stop)
+{
+ printf("attach_debugger called when CONFIG_PT_PROXY "
+ "is off\n");
+ return(-1);
+}
+
+int config_gdb(char *str)
+{
+ return(-1);
+}
+
+int remove_gdb(void)
+{
+ return(-1);
+}
+
+int init_parent_proxy(int pid)
+{
+ return(-1);
+}
+
+void debugger_parent_signal(int status, int pid)
+{
+}
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only. This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
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