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Diffstat (limited to 'arch/um/kernel/tt/tracer.c')
-rw-r--r--arch/um/kernel/tt/tracer.c461
1 files changed, 0 insertions, 461 deletions
diff --git a/arch/um/kernel/tt/tracer.c b/arch/um/kernel/tt/tracer.c
deleted file mode 100644
index c23588393f6..00000000000
--- a/arch/um/kernel/tt/tracer.c
+++ /dev/null
@@ -1,461 +0,0 @@
-/*
- * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
- * Licensed under the GPL
- */
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdarg.h>
-#include <unistd.h>
-#include <signal.h>
-#include <errno.h>
-#include <sched.h>
-#include <string.h>
-#include <sys/mman.h>
-#include <sys/time.h>
-#include <sys/wait.h>
-#include "user.h"
-#include "sysdep/ptrace.h"
-#include "sigcontext.h"
-#include "sysdep/sigcontext.h"
-#include "os.h"
-#include "mem_user.h"
-#include "process.h"
-#include "kern_util.h"
-#include "chan_user.h"
-#include "ptrace_user.h"
-#include "irq_user.h"
-#include "mode.h"
-#include "tt.h"
-
-static int tracer_winch[2];
-
-int is_tracer_winch(int pid, int fd, void *data)
-{
- if(pid != os_getpgrp())
- return(0);
-
- register_winch_irq(tracer_winch[0], fd, -1, data);
- return(1);
-}
-
-static void tracer_winch_handler(int sig)
-{
- int n;
- char c = 1;
-
- n = os_write_file(tracer_winch[1], &c, sizeof(c));
- if(n != sizeof(c))
- printk("tracer_winch_handler - write failed, err = %d\n", -n);
-}
-
-/* Called only by the tracing thread during initialization */
-
-static void setup_tracer_winch(void)
-{
- int err;
-
- err = os_pipe(tracer_winch, 1, 1);
- if(err < 0){
- printk("setup_tracer_winch : os_pipe failed, err = %d\n", -err);
- return;
- }
- signal(SIGWINCH, tracer_winch_handler);
-}
-
-void attach_process(int pid)
-{
- if((ptrace(PTRACE_ATTACH, pid, 0, 0) < 0) ||
- (ptrace(PTRACE_CONT, pid, 0, 0) < 0))
- tracer_panic("OP_FORK failed to attach pid");
- wait_for_stop(pid, SIGSTOP, PTRACE_CONT, NULL);
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, 0, (void *)PTRACE_O_TRACESYSGOOD) < 0)
- tracer_panic("OP_FORK: PTRACE_SETOPTIONS failed, errno = %d", errno);
- if(ptrace(PTRACE_CONT, pid, 0, 0) < 0)
- tracer_panic("OP_FORK failed to continue process");
-}
-
-void tracer_panic(char *format, ...)
-{
- va_list ap;
-
- va_start(ap, format);
- vprintf(format, ap);
- va_end(ap);
- printf("\n");
- while(1) pause();
-}
-
-static void tracer_segv(int sig, struct sigcontext sc)
-{
- struct faultinfo fi;
- GET_FAULTINFO_FROM_SC(fi, &sc);
- printf("Tracing thread segfault at address 0x%lx, ip 0x%lx\n",
- FAULT_ADDRESS(fi), SC_IP(&sc));
- while(1)
- pause();
-}
-
-/* Changed early in boot, and then only read */
-int debug = 0;
-int debug_stop = 1;
-int debug_parent = 0;
-int honeypot = 0;
-
-static int signal_tramp(void *arg)
-{
- int (*proc)(void *);
-
- if(honeypot && munmap((void *) (host_task_size - 0x10000000),
- 0x10000000))
- panic("Unmapping stack failed");
- if(ptrace(PTRACE_TRACEME, 0, 0, 0) < 0)
- panic("ptrace PTRACE_TRACEME failed");
- os_stop_process(os_getpid());
- change_sig(SIGWINCH, 0);
- signal(SIGUSR1, SIG_IGN);
- change_sig(SIGCHLD, 0);
- signal(SIGSEGV, (__sighandler_t) sig_handler);
- set_cmdline("(idle thread)");
- set_init_pid(os_getpid());
- init_irq_signals(0);
- proc = arg;
- return((*proc)(NULL));
-}
-
-static void sleeping_process_signal(int pid, int sig)
-{
- switch(sig){
- /* These two result from UML being ^Z-ed and bg-ed. PTRACE_CONT is
- * right because the process must be in the kernel already.
- */
- case SIGCONT:
- case SIGTSTP:
- if(ptrace(PTRACE_CONT, pid, 0, sig) < 0)
- tracer_panic("sleeping_process_signal : Failed to "
- "continue pid %d, signal = %d, "
- "errno = %d\n", pid, sig, errno);
- break;
-
- /* This happens when the debugger (e.g. strace) is doing system call
- * tracing on the kernel. During a context switch, the current task
- * will be set to the incoming process and the outgoing process will
- * hop into write and then read. Since it's not the current process
- * any more, the trace of those will land here. So, we need to just
- * PTRACE_SYSCALL it.
- */
- case (SIGTRAP + 0x80):
- if(ptrace(PTRACE_SYSCALL, pid, 0, 0) < 0)
- tracer_panic("sleeping_process_signal : Failed to "
- "PTRACE_SYSCALL pid %d, errno = %d\n",
- pid, errno);
- break;
- case SIGSTOP:
- break;
- default:
- tracer_panic("sleeping process %d got unexpected "
- "signal : %d\n", pid, sig);
- break;
- }
-}
-
-/* Accessed only by the tracing thread */
-int debugger_pid = -1;
-int debugger_parent = -1;
-int debugger_fd = -1;
-int gdb_pid = -1;
-
-struct {
- int pid;
- int signal;
- unsigned long addr;
- struct timeval time;
-} signal_record[1024][32];
-
-int signal_index[32];
-int nsignals = 0;
-int debug_trace = 0;
-
-extern void signal_usr1(int sig);
-
-int tracing_pid = -1;
-
-int tracer(int (*init_proc)(void *), void *sp)
-{
- void *task = NULL;
- int status, pid = 0, sig = 0, cont_type, tracing = 0, op = 0;
- int proc_id = 0, n, err, old_tracing = 0, strace = 0;
- int local_using_sysemu = 0;
-
- signal(SIGPIPE, SIG_IGN);
- setup_tracer_winch();
- tracing_pid = os_getpid();
- printf("tracing thread pid = %d\n", tracing_pid);
-
- pid = clone(signal_tramp, sp, CLONE_FILES | SIGCHLD, init_proc);
- CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED));
- if(n < 0){
- printf("waitpid on idle thread failed, errno = %d\n", errno);
- exit(1);
- }
- if (ptrace(PTRACE_OLDSETOPTIONS, pid, 0, (void *)PTRACE_O_TRACESYSGOOD) < 0) {
- printf("Failed to PTRACE_SETOPTIONS for idle thread, errno = %d\n", errno);
- exit(1);
- }
- if((ptrace(PTRACE_CONT, pid, 0, 0) < 0)){
- printf("Failed to continue idle thread, errno = %d\n", errno);
- exit(1);
- }
-
- signal(SIGSEGV, (sighandler_t) tracer_segv);
- signal(SIGUSR1, signal_usr1);
- if(debug_trace){
- printf("Tracing thread pausing to be attached\n");
- stop();
- }
- if(debug){
- if(gdb_pid != -1)
- debugger_pid = attach_debugger(pid, gdb_pid, 1);
- else debugger_pid = init_ptrace_proxy(pid, 1, debug_stop);
- if(debug_parent){
- debugger_parent = os_process_parent(debugger_pid);
- init_parent_proxy(debugger_parent);
- err = attach(debugger_parent);
- if(err){
- printf("Failed to attach debugger parent %d, "
- "errno = %d\n", debugger_parent, -err);
- debugger_parent = -1;
- }
- else {
- if(ptrace(PTRACE_SYSCALL, debugger_parent,
- 0, 0) < 0){
- printf("Failed to continue debugger "
- "parent, errno = %d\n", errno);
- debugger_parent = -1;
- }
- }
- }
- }
- set_cmdline("(tracing thread)");
- while(1){
- CATCH_EINTR(pid = waitpid(-1, &status, WUNTRACED));
- if(pid <= 0){
- if(errno != ECHILD){
- printf("wait failed - errno = %d\n", errno);
- }
- continue;
- }
- if(pid == debugger_pid){
- int cont = 0;
-
- if(WIFEXITED(status) || WIFSIGNALED(status))
- debugger_pid = -1;
- /* XXX Figure out how to deal with gdb and SMP */
- else cont = debugger_signal(status, cpu_tasks[0].pid);
- if(cont == PTRACE_SYSCALL) strace = 1;
- continue;
- }
- else if(pid == debugger_parent){
- debugger_parent_signal(status, pid);
- continue;
- }
- nsignals++;
- if(WIFEXITED(status)) ;
-#ifdef notdef
- {
- printf("Child %d exited with status %d\n", pid,
- WEXITSTATUS(status));
- }
-#endif
- else if(WIFSIGNALED(status)){
- sig = WTERMSIG(status);
- if(sig != 9){
- printf("Child %d exited with signal %d\n", pid,
- sig);
- }
- }
- else if(WIFSTOPPED(status)){
- proc_id = pid_to_processor_id(pid);
- sig = WSTOPSIG(status);
- if(proc_id == -1){
- sleeping_process_signal(pid, sig);
- continue;
- }
-
- task = cpu_tasks[proc_id].task;
- tracing = is_tracing(task);
- old_tracing = tracing;
-
- /* Assume: no syscall, when coming from user */
- if ( tracing )
- do_sigtrap(task);
-
- switch(sig){
- case SIGUSR1:
- sig = 0;
- op = do_proc_op(task, proc_id);
- switch(op){
- /*
- * This is called when entering user mode; after
- * this, we start intercepting syscalls.
- *
- * In fact, a process is started in kernel mode,
- * so with is_tracing() == 0 (and that is reset
- * when executing syscalls, since UML kernel has
- * the right to do syscalls);
- */
- case OP_TRACE_ON:
- arch_leave_kernel(task, pid);
- tracing = 1;
- break;
- case OP_REBOOT:
- case OP_HALT:
- unmap_physmem();
- kmalloc_ok = 0;
- os_kill_ptraced_process(pid, 0);
- /* Now let's reap remaining zombies */
- errno = 0;
- do {
- waitpid(-1, &status,
- WUNTRACED);
- } while (errno != ECHILD);
- return(op == OP_REBOOT);
- case OP_NONE:
- printf("Detaching pid %d\n", pid);
- detach(pid, SIGSTOP);
- continue;
- default:
- break;
- }
- /* OP_EXEC switches host processes on us,
- * we want to continue the new one.
- */
- pid = cpu_tasks[proc_id].pid;
- break;
- case (SIGTRAP + 0x80):
- if(!tracing && (debugger_pid != -1)){
- child_signal(pid, status & 0x7fff);
- continue;
- }
- tracing = 0;
- /* local_using_sysemu has been already set
- * below, since if we are here, is_tracing() on
- * the traced task was 1, i.e. the process had
- * already run through one iteration of the
- * loop which executed a OP_TRACE_ON request.*/
- do_syscall(task, pid, local_using_sysemu);
- sig = SIGUSR2;
- break;
- case SIGTRAP:
- if(!tracing && (debugger_pid != -1)){
- child_signal(pid, status);
- continue;
- }
- tracing = 0;
- break;
- case SIGPROF:
- if(tracing) sig = 0;
- break;
- case SIGCHLD:
- case SIGHUP:
- sig = 0;
- break;
- case SIGSEGV:
- case SIGIO:
- case SIGALRM:
- case SIGVTALRM:
- case SIGFPE:
- case SIGBUS:
- case SIGILL:
- case SIGWINCH:
-
- default:
- tracing = 0;
- break;
- }
- set_tracing(task, tracing);
-
- if(!tracing && old_tracing)
- arch_enter_kernel(task, pid);
-
- if(!tracing && (debugger_pid != -1) && (sig != 0) &&
- (sig != SIGALRM) && (sig != SIGVTALRM) &&
- (sig != SIGSEGV) && (sig != SIGTRAP) &&
- (sig != SIGUSR2) && (sig != SIGIO) &&
- (sig != SIGFPE)){
- child_signal(pid, status);
- continue;
- }
-
- local_using_sysemu = get_using_sysemu();
-
- if(tracing)
- cont_type = SELECT_PTRACE_OPERATION(local_using_sysemu,
- singlestepping(task));
- else if((debugger_pid != -1) && strace)
- cont_type = PTRACE_SYSCALL;
- else
- cont_type = PTRACE_CONT;
-
- if(ptrace(cont_type, pid, 0, sig) != 0){
- tracer_panic("ptrace failed to continue "
- "process - errno = %d\n",
- errno);
- }
- }
- }
- return(0);
-}
-
-static int __init uml_debug_setup(char *line, int *add)
-{
- char *next;
-
- debug = 1;
- *add = 0;
- if(*line != '=') return(0);
- line++;
-
- while(line != NULL){
- next = strchr(line, ',');
- if(next) *next++ = '\0';
-
- if(!strcmp(line, "go")) debug_stop = 0;
- else if(!strcmp(line, "parent")) debug_parent = 1;
- else printf("Unknown debug option : '%s'\n", line);
-
- line = next;
- }
- return(0);
-}
-
-__uml_setup("debug", uml_debug_setup,
-"debug\n"
-" Starts up the kernel under the control of gdb. See the \n"
-" kernel debugging tutorial and the debugging session pages\n"
-" at http://user-mode-linux.sourceforge.net/ for more information.\n\n"
-);
-
-static int __init uml_debugtrace_setup(char *line, int *add)
-{
- debug_trace = 1;
- return 0;
-}
-__uml_setup("debugtrace", uml_debugtrace_setup,
-"debugtrace\n"
-" Causes the tracing thread to pause until it is attached by a\n"
-" debugger and continued. This is mostly for debugging crashes\n"
-" early during boot, and should be pretty much obsoleted by\n"
-" the debug switch.\n\n"
-);
-
-/*
- * 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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