rpms/gdb
7
0
Fork 0
Code Issues Pull Requests Releases Activity

- Fix attaching to stopped processes and/or pending signals.

Browse Source
This commit is contained in:
Jan Kratochvil 2007-09-16 22:34:35 +00:00
parent 4e2e7886e3
commit 41705867ad
2 changed files with 398 additions and 293 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

684
gdb-6.6-bz233852-attach-signalled.patch
View File

@ -1,271 +1,117 @@
diff -u -rup gdb-6.6-orig/gdb/inf-ptrace.c gdb-6.6/gdb/inf-ptrace.c 2007-07-01 Jan Kratochvil <jan.kratochvil@redhat.com>
--- gdb-6.6-orig/gdb/inf-ptrace.c 2006-01-24 23:34:34.000000000 +0100
+++ gdb-6.6/gdb/inf-ptrace.c 2007-06-06 13:33:11.000000000 +0200 * linux-nat.h (struct lwp_info): New field WAS_STOPPED.
@@ -38,6 +38,9 @@ * linux-nat.c (STRINGIFY, STRINGIFY_ARG): New macros.
(kill_lwp): New declaration.
(linux_ptrace_post_attach, pid_is_stopped): New function.
(linux_child_follow_fork): New comment about WAS_STOPPED.
(lin_lwp_attach_lwp): Variable PID removed. Part replaced by a call to
LINUX_PTRACE_POST_ATTACH.
(linux_nat_attach): Likewise.
(linux_nat_detach): Optionally stop the detached process.
(linux_nat_resume): Clear WAS_STOPPED if appropriate.
* NEWS: Document the new behaviour.
2007-06-30 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.threads/attach-into-signal.c, gdb.threads/attach-into-signal.exp,
gdb.threads/attach-stopped.c, gdb.threads/attach-stopped.exp: New files.
2007-06-30 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.texinfo (Attach): Document the ATTACH and DETACH commands for
stopped processes. Document the messages on the seen pending signals.
[ Backport for GDB-6.6. ]
--- ./gdb/NEWS 21 Jun 2007 15:18:50 -0000 1.232
+++ ./gdb/NEWS 30 Jun 2007 16:27:37 -0000
@@ -44,6 +44,9 @@ segment base addresses (rather than offs
* The /i format now outputs any trailing branch delay slot instructions
immediately following the last instruction within the count specified.
/* HACK: Save the ptrace ops returned by inf_ptrace_target. */ +* On GNU/Linux, stopped processes may get attached to now. Signals being
static struct target_ops *ptrace_ops_hack; +delivered at the time of the attach command no longer get lost.
+ +
+/* Stored PID of the process being stopped during attach. */ * New commands
+static pid_t stopped_pid;
#ifdef PT_GET_PROCESS_STATE
@@ -69,14 +72,20 @@ inf_ptrace_follow_fork (struct target_op
if (follow_child)
{
+ unsigned long sig = 0;
+
inferior_ptid = pid_to_ptid (fpid);
detach_breakpoints (pid);
/* Reset breakpoints in the child as appropriate. */
follow_inferior_reset_breakpoints ();
- if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, 0) == -1)
- perror_with_name (("ptrace"));
+ /* Stop the process again if it was stopped during the attachment. */
+ if (pid == stopped_pid)
+ sig = target_signal_to_host (TARGET_SIGNAL_STOP));
+
+ if (ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, (void *) sig) == -1)
+ perror_with_name (("ptrace PT_DETACH"));
}
else
{
@@ -173,6 +182,21 @@ inf_ptrace_mourn_inferior (void)
generic_mourn_inferior ();
}
+/* Wrapper function for waitpid which handles EINTR. */
+
+static int
+my_waitpid (int pid, int *status, int flags)
+{
+ int ret;
+ do
+ {
+ ret = waitpid (pid, status, flags);
+ }
+ while (ret == -1 && errno == EINTR);
+
+ return ret;
+}
+
/* Attach to the process specified by ARGS. If FROM_TTY is non-zero,
be chatty about it. */
@@ -180,8 +204,14 @@ static void
inf_ptrace_attach (char *args, int from_tty)
{
char *exec_file;
- pid_t pid;
+ pid_t pid, got_pid;
char *dummy;
+ int status;
+ unsigned long sig;
+ FILE *status_file;
+ char name[40];
+ char buf[100];
+ int sigstop = target_signal_to_host (TARGET_SIGNAL_STOP);
if (!args)
error_no_arg (_("process-id to attach"));
@@ -210,11 +240,64 @@ inf_ptrace_attach (char *args, int from_
}
#ifdef PT_ATTACH
+ stopped_pid = 0;
+ /* There is a small moment after PTRACE_ATTACH where PTRACE_CONT will
+ succeed only for originally stopped processes. Unfortunately in a moment
+ PTRACE_ATTACH will deliver its SIGSTOP and PTRACE_CONT shows no difference
+ since that moment.
+ "/proc/%d/status" is also a race but it is safe for unstopped cases. */
+ sprintf (name, "/proc/%d/status", (int) pid);
+ status_file = fopen (name, "r");
+ if (status_file != NULL)
+ {
+ int have_state = 0;
+
+ while (fgets (buf, 100, status_file))
+ {
+ if (strncmp (buf, "State:", 6) == 0)
+ {
+ have_state = 1;
+ break;
+ }
+ }
+ if (have_state != 0 && strstr (buf, "T (stopped)") != NULL)
+ stopped_pid = pid;
+ fclose (status_file);
+ }
+
errno = 0;
ptrace (PT_ATTACH, pid, (PTRACE_TYPE_ARG3)0, 0);
if (errno != 0)
perror_with_name (("ptrace"));
attach_flag = 1;
+
+ /* Deliver one SIGSTOP just for sure.
+ If the process was already stopped AND some other process (like shell)
+ has already waited for it we would get stuck in waitpid (). */
+ sig = sigstop;
+ do
+ {
+ if (sig != sigstop)
+ printf_unfiltered (_("Redelivering pending %s.\n"),
+ target_signal_to_string (target_signal_from_host (sig)));
+ errno = 0;
+ ptrace (PT_CONTINUE, pid, (PTRACE_TYPE_ARG3)1, (void *) sig);
+ /* For unstopped processes the preventive signal may ESRCH. */
+ if (errno != 0 && sig != sigstop)
+ perror_with_name ("ptrace PT_CONTINUE");
+
+ got_pid = my_waitpid (pid, &status, 0);
+ gdb_assert (got_pid == pid);
+
+ /* Check if the thread has exited. */
+ if (WIFEXITED (status) || WIFSIGNALED (status))
+ error (_("Program %s exited.\n"),
+ target_pid_to_str (pid_to_ptid (pid)));
+ gdb_assert (WIFSTOPPED (status));
+ sig = WSTOPSIG (status);
+ gdb_assert (sig != 0);
+ }
+ while (sig != sigstop);
#else
error (_("This system does not support attaching to a process"));
#endif
@@ -240,14 +323,16 @@ inf_ptrace_post_attach (int pid)
set remoteflow
--- gdb-6.6/gdb/linux-nat.c-orig-orig 2007-09-16 20:57:13.000000000 +0200
+++ gdb-6.6/gdb/linux-nat.c 2007-09-16 21:02:28.000000000 +0200
@@ -87,6 +87,12 @@
#define __WALL 0x40000000 /* Wait for any child. */
#endif #endif
-/* Detach from the inferior, optionally passing it the signal +#define STRINGIFY_ARG(x) #x
- specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ +#define STRINGIFY(x) STRINGIFY_ARG (x)
+/* Detach from the inferior. If FROM_TTY is non-zero, be chatty about it. */
static void
inf_ptrace_detach (char *args, int from_tty)
{
pid_t pid = ptid_get_pid (inferior_ptid);
- int sig = 0;
+ unsigned long sig = 0;
+ +
+ if (args) +static int linux_ptrace_post_attach (struct lwp_info *lp);
+ error (_("Too many arguments")); +static int kill_lwp (int lwpid, int signo);
if (from_tty)
{
@@ -258,18 +343,19 @@ inf_ptrace_detach (char *args, int from_
target_pid_to_str (pid_to_ptid (pid)));
gdb_flush (gdb_stdout);
}
- if (args)
- sig = atoi (args);
#ifdef PT_DETACH
/* We'd better not have left any breakpoints in the program or it'll
die when it hits one. Also note that this may only work if we
previously attached to the inferior. It *might* work if we
started the process ourselves. */
+ /* Stop the process again if it was stopped during the attachment. */
+ if (pid == stopped_pid)
+ sig = target_signal_to_host (TARGET_SIGNAL_STOP);
errno = 0;
- ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, sig);
+ ptrace (PT_DETACH, pid, (PTRACE_TYPE_ARG3)1, (void *) sig);
if (errno != 0)
- perror_with_name (("ptrace"));
+ perror_with_name (("ptrace PT_DETACH"));
attach_flag = 0;
#else
error (_("This system does not support detaching from a process"));
@@ -324,6 +410,12 @@ inf_ptrace_resume (ptid_t ptid, int step
single-threaded processes, so simply resume the inferior. */
pid = ptid_get_pid (inferior_ptid);
+ /* At this point, we are going to resume the inferior and if we
+ have attached to a stopped process, we no longer should leave
+ it as stopped if the user detaches. */
+ if (!step && pid == stopped_pid)
+ stopped_pid = 0;
+ +
if (step) /* The single-threaded native GNU/Linux target_ops. We save a pointer for
the use of the multi-threaded target. */
static struct target_ops *linux_ops;
@@ -533,6 +539,11 @@ child_follow_fork (struct target_ops *op
}
else
{
+ /* We should check LP->WAS_STOPPED and detach it stopped accordingly.
+ In this point of code it cannot be 1 as we would not get FORK
+ executed without CONTINUE first which resets LP->WAS_STOPPED.
+ We would have to first TARGET_STOP and WAITPID it as with running
+ inferior PTRACE_DETACH, SIGSTOP will ignore the signal. */
target_detach (NULL, 0);
}
@@ -992,7 +1003,6 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver
to happen. */
if (GET_LWP (ptid) != GET_PID (ptid) && lp == NULL)
{ {
/* If this system does not support PT_STEP, a higher level - pid_t pid;
diff -u -rup gdb-6.6-orig/gdb/linux-nat.c gdb-6.6/gdb/linux-nat.c
--- gdb-6.6-orig/gdb/linux-nat.c 2007-06-06 13:30:52.000000000 +0200
+++ gdb-6.6/gdb/linux-nat.c 2007-06-06 13:57:18.000000000 +0200
@@ -994,6 +994,7 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver
{
pid_t pid;
int status; int status;
+ unsigned long sig;
if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0) if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0)
{ @@ -1002,45 +1012,23 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver
@@ -1015,32 +1016,54 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver creation is interrupted; as of Linux 2.6.19, a kernel
"LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", bug may place threads in the thread list and then fail
target_pid_to_str (ptid)); to create them. */
- warning (_("Can't attach %s: %s"), target_pid_to_str (ptid),
- safe_strerror (errno));
- return -1;
+ error (_("Can't attach %s: %s"), target_pid_to_str (ptid),
+ safe_strerror (errno));
}
if (lp == NULL)
lp = add_lwp (ptid);
- if (debug_linux_nat)
- fprintf_unfiltered (gdb_stdlog,
- "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
- target_pid_to_str (ptid));
-
- pid = my_waitpid (GET_LWP (ptid), &status, 0); - pid = my_waitpid (GET_LWP (ptid), &status, 0);
- if (pid == -1 && errno == ECHILD) - if (pid == -1 && errno == ECHILD)
+ sig = SIGSTOP; - {
+ do
{
- /* Try again with __WCLONE to check cloned processes. */ - /* Try again with __WCLONE to check cloned processes. */
- pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE); - pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE);
+ if (sig != SIGSTOP) - if (pid == -1 && errno == ECHILD)
+ printf_unfiltered (_("Redelivering pending %s.\n"),
+ target_signal_to_string (target_signal_from_host (sig)));
+ /* For unstopped processes the preventive signal may ESRCH. */
+ if (ptrace (PTRACE_CONT, GET_LWP (ptid), (PTRACE_TYPE_ARG3)1,
+ (void *) sig) != 0 && sig != SIGSTOP)
+ perror_with_name ("ptrace");
+
+ pid = my_waitpid (GET_LWP (ptid), &status, 0);
if (pid == -1 && errno == ECHILD)
- error (_("Can't attach %s (%s) - possible SELinux denial," - error (_("Can't attach %s (%s) - possible SELinux denial,"
- " check your /var/log/messages for `avc: denied'"), - " check your /var/log/messages for `avc: denied'"),
- target_pid_to_str (ptid), safe_strerror (errno)); - target_pid_to_str (ptid), safe_strerror (errno));
- lp->cloned = 1; - lp->cloned = 1;
- } + status = linux_ptrace_post_attach (lp);
+ { + if (status != 0)
+ /* Try again with __WCLONE to check cloned processes. */ + {
+ pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE); + error (_("Thread %s exited: %s"), target_pid_to_str (ptid),
+ if (pid == -1 && errno == ECHILD) + status_to_str (status));
+ error (_("Can't attach %s (%s) - possible SELinux denial," }
+ " check your /var/log/messages for `avc: denied'"),
+ target_pid_to_str (ptid), safe_strerror (errno));
+ lp->cloned = 1;
+ }
+ gdb_assert (pid == GET_LWP (ptid));
- gdb_assert (pid == GET_LWP (ptid) - gdb_assert (pid == GET_LWP (ptid)
- && WIFSTOPPED (status) && WSTOPSIG (status)); - && WIFSTOPPED (status) && WSTOPSIG (status));
+ if (debug_linux_nat) -
+ { - target_post_attach (pid);
+ fprintf_unfiltered (gdb_stdlog, + target_post_attach (GET_LWP (ptid));
+ "LLAL: waitpid %s received %s\n",
+ target_pid_to_str (ptid),
+ status_to_str (status));
+ }
+
+ /* Check if the thread has exited. */
+ if (WIFEXITED (status) || WIFSIGNALED (status))
+ {
+ warning (_("Thread %s exited: %s"), target_pid_to_str (ptid),
+ status_to_str (status));
+ return -1;
+ }
+ gdb_assert (WIFSTOPPED (status));
+ sig = WSTOPSIG (status);
+ gdb_assert (sig != 0);
+ }
+ while (sig != SIGSTOP);
target_post_attach (pid);
lp->stopped = 1; lp->stopped = 1;
- -
@ -279,16 +125,181 @@ diff -u -rup gdb-6.6-orig/gdb/linux-nat.c gdb-6.6/gdb/linux-nat.c
} }
else else
{ {
@@ -1065,8 +1088,6 @@ static void @@ -1061,11 +1049,172 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver
return 0;
}
+/* Detect `T (stopped)' in `/proc/PID/status'.
+ Other states including `T (tracing stop)' are reported as false. */
+
+static int
+pid_is_stopped (pid_t pid)
+{
+ FILE *status_file;
+ char buf[100];
+ int retval = 0;
+
+ snprintf (buf, sizeof (buf), "/proc/%d/status", (int) pid);
+ status_file = fopen (buf, "r");
+ if (status_file != NULL)
+ {
+ int have_state = 0;
+
+ while (fgets (buf, sizeof (buf), status_file))
+ {
+ if (strncmp (buf, "State:", 6) == 0)
+ {
+ have_state = 1;
+ break;
+ }
+ }
+ if (have_state && strstr (buf, "T (stopped)") != NULL)
+ retval = 1;
+ fclose (status_file);
+ }
+ return retval;
+}
+
+/* Handle the processing after PTRACE_ATTACH, the first WAITPID -> SIGSTOP.
+ Returns STATUS if the thread has exited, 0 otherwise.
+ Sets LP->WAS_STOPPED if the process was originally stopped.
+ Sets LP->CLONED if the given LWP is not the thread leader.
+
+ Scenario for a standard unstopped inferior:
+ * `S (sleeping)' or `R (running)' or similiar states.
+ * PTRACE_ATTACH is called.
+ * `S (sleeping)' (or similiar) for some while.
+ * `T (tracing stop)'.
+ * WAITPID succeeds here returning SIGSTOP (signalled by PTRACE_ATTACH).
+
+ Scenario for a formerly stopped inferior:
+ * `T (stopped)'.
+ * PTRACE_ATTACH is called.
+ * `T (stopped)' would stay indefinitely
+ Note since this moment the `TracerPid' field gets filled
+ (by PTRACE_ATTACH), it is no longer just the common `T (stopped)' state.
+ * If no one did WAITPID since sending SIGSTOP our WAITPID would return
+ SIGSTOP. The state still would not turn to `T (tracing stop)'.
+ * Usually its original parent (before PTRACE_ATTACH was applied) already
+ did WAITPID. The original parent already received our SIGSTOP
+ sinalled by our PTRACE_ATTACH.
+ In this case our own WAITPID would hang. Therefore...
+ * ... we do artificial: tkill (SIGCONT);
+ `PTRACE_CONT, SIGSTOP' does not work in 100% cases as sometimes SIGSTOP
+ gets remembered by kernel during the first PTRACE_CONT later and we get
+ spurious SIGSTOP event. Expecting the signal may get delivered to
+ a different task of the thread group.
+ `kill_lwp (SIGSTOP)' has no effect in this moment (it is already stopped).
+ * WAITPID returns the artifical SIGCONT.
+ (The possibly pending SIGSTOP gets vanished by specifically SIGCONT.)
+ * State turns `T (tracing stop)'.
+ In this moment everything is almost fine but we need a workaround as final
+ `PTRACE_DETACH, SIGSTOP' would leave the process unstopped otherwise:
+ * tkill (SIGSTOP);
+ * `PTRACE_CONT, 0'
+ * WAITPID returns the artifical SIGSTOP.
+
+ With the pending (unwaited for) SIGSTOP the artifical signal effects are:
+ kill (SIGSTOP)
+ PTRACE_ATTACH
+ /-tkill (SIGCONT), WAITPID: SIGCONT, WAITPID: hang !
+ //-tkill (SIGCONT), WAITPID: SIGCONT, PTRACE_CONT (SIG_0), WAITPID: wait (OK)
+ \\-tkill (SIGALRM), WAITPID: SIGSTOP, WAITPID: hang !
+ \-tkill (SIGALRM), WAITPID: SIGSTOP, PTRACE_CONT (SIG_0), WAITPID: SIGALRM !
+ Therefore we signal artifical SIGCONT and stop waiting after its reception.
+
+ For the detection whether the process was formerly stopped we need to
+ read `/proc/PID/status'. `PTRACE_CONT, SIGSTOP' returns ESRCH
+ for `S (sleeping)' and succeeds for `T (stopped)' but it unfortunately
+ succeeds even for `T (tracing stop)'. Depending on PTRACE_CONT, SIGSTOP
+ success value for formerly stopped processes would mean a race condition
+ as we would get false stopped processes detection if we get too slow.
+
+ `waitid (..., WSTOPPED)' hangs the same way as WAITPID.
+
+ Signals get queued for WAITPID. PTRACE_ATTACH (or TKILL) enqueues SIGSTOP
+ there but WAITPID may return an already pending signal.
+ Redeliver it by PTRACE_CONT, SIGxxx as otherwise it would get lost.
+ Similiar processing is being done in this file by WAIT_LWP. */
+
+static int
+linux_ptrace_post_attach (struct lwp_info *lp)
+{
+ ptid_t ptid = lp->ptid;
+ unsigned long sig;
+
+ if (debug_linux_nat)
+ fprintf_unfiltered (gdb_stdlog,
+ "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n",
+ target_pid_to_str (ptid));
+
+ lp->was_stopped = pid_is_stopped (GET_LWP (ptid));
+ if (lp->was_stopped)
+ {
+ if (kill_lwp (GET_LWP (ptid), SIGCONT) != 0)
+ perror_with_name (("kill_lwp (SIGCONT)"));
+ }
+
+ for (;;)
+ {
+ pid_t pid;
+ int status;
+
+ pid = my_waitpid (GET_LWP (ptid), &status, 0);
+ if (pid == -1 && errno == ECHILD)
+ {
+ /* Try again with __WCLONE to check cloned processes. */
+ pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE);
+ lp->cloned = 1;
+ }
+ gdb_assert (pid == GET_LWP (ptid));
+
+ if (debug_linux_nat)
+ {
+ fprintf_unfiltered (gdb_stdlog,
+ "LLAL: waitpid %s received %s\n",
+ target_pid_to_str (ptid),
+ status_to_str (status));
+ }
+
+ /* Check if the thread has exited. */
+ if (WIFEXITED (status) || WIFSIGNALED (status))
+ return status;
+ gdb_assert (WIFSTOPPED (status));
+ sig = WSTOPSIG (status);
+ gdb_assert (sig != 0);
+ if (sig == SIGSTOP)
+ break;
+
+ /* As the second signal for stopped processes we send SIGSTOP. */
+ if (lp->was_stopped && sig == SIGCONT)
+ sig = SIGSTOP;
+
+ printf_unfiltered (_("Redelivering pending %s.\n"),
+ target_signal_to_string (target_signal_from_host (sig)));
+ if (sig == SIGSTOP)
+ {
+ if (kill_lwp (GET_LWP (ptid), sig) != 0)
+ perror_with_name (("kill_lwp"));
+ /* We now must resume the inferior to get SIGSTOP delivered. */
+ sig = 0;
+ }
+ if (ptrace (PTRACE_CONT, GET_LWP (ptid), NULL, (void *) sig) != 0)
+ perror_with_name (("ptrace"));
+ }
+
+ return 0;
+}
+
static void
linux_nat_attach (char *args, int from_tty) linux_nat_attach (char *args, int from_tty)
{ {
struct lwp_info *lp; struct lwp_info *lp;
- pid_t pid; - pid_t pid;
- int status; int status;
/* FIXME: We should probably accept a list of process id's, and /* FIXME: We should probably accept a list of process id's, and
attach all of them. */ @@ -1076,21 +1225,12 @@ linux_nat_attach (char *args, int from_t
@@ -1076,22 +1097,6 @@ linux_nat_attach (char *args, int from_t
inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid)); inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (inferior_ptid));
lp = add_lwp (inferior_ptid); lp = add_lwp (inferior_ptid);
@ -307,11 +318,16 @@ diff -u -rup gdb-6.6-orig/gdb/linux-nat.c gdb-6.6/gdb/linux-nat.c
- -
- gdb_assert (pid == GET_PID (inferior_ptid) - gdb_assert (pid == GET_PID (inferior_ptid)
- && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP); - && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP);
- + status = linux_ptrace_post_attach (lp);
+ if (status != 0)
+ error (_("Program %s exited: %s\n"), target_pid_to_str (inferior_ptid),
+ status_to_str (status));
+ if (lp->cloned)
+ warning (_("%s is a cloned process"), target_pid_to_str (inferior_ptid));
lp->stopped = 1; lp->stopped = 1;
/* Fake the SIGSTOP that core GDB expects. */ @@ -1099,8 +1239,8 @@ linux_nat_attach (char *args, int from_t
@@ -1099,8 +1104,8 @@ linux_nat_attach (char *args, int from_t
lp->resumed = 1; lp->resumed = 1;
if (debug_linux_nat) if (debug_linux_nat)
{ {
@ -322,26 +338,44 @@ diff -u -rup gdb-6.6-orig/gdb/linux-nat.c gdb-6.6/gdb/linux-nat.c
} }
} }
diff -u -rup gdb-6.6-orig/gdb/target.h gdb-6.6/gdb/target.h @@ -1173,6 +1313,9 @@ linux_nat_detach (char *args, int from_t
--- gdb-6.6-orig/gdb/target.h 2007-06-06 13:30:52.000000000 +0200
+++ gdb-6.6/gdb/target.h 2007-06-06 13:33:11.000000000 +0200
@@ -529,9 +529,9 @@ void target_close (struct target_ops *ta
to the `attach' command by the user. This routine can be called
when the target is not on the target-stack, if the target_can_run
routine returns 1; in that case, it must push itself onto the stack.
- Upon exit, the target should be ready for normal operations, and
- should be ready to deliver the status of the process immediately
- (without waiting) to an upcoming target_wait call. */
+ Upon exit, the target should be ready for normal operations.
+ The status of the inferior is already processed and possibly pending
+ signals redelivered. */
#define target_attach(args, from_tty) \ trap_ptid = null_ptid;
(*current_target.to_attach) (args, from_tty)
diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.c gdb-6.6/gdb/testsuite/gdb.threads/attach-into-signal.c + if (lwp_list->was_stopped)
--- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.c 2007-06-06 16:36:34.000000000 +0200 + args = STRINGIFY (SIGSTOP);
+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-into-signal.c 2007-06-06 13:33:11.000000000 +0200 +
@@ -0,0 +1,65 @@ /* Destroy LWP info; it's no longer valid. */
init_lwp_list ();
@@ -1310,6 +1453,12 @@ linux_nat_resume (ptid_t ptid, int step_
lp->stopped = 0;
}
+ /* At this point, we are going to resume the inferior and if we
+ have attached to a stopped process, we no longer should leave
+ it as stopped if the user detaches. */
+ if (!step && lp != NULL)
+ lp->was_stopped = 0;
+
if (resume_all)
iterate_over_lwps (resume_callback, NULL);
--- ./gdb/linux-nat.h 10 May 2007 21:36:00 -0000 1.18
+++ ./gdb/linux-nat.h 29 Jun 2007 22:06:05 -0000
@@ -42,6 +42,9 @@ struct lwp_info
/* Non-zero if this LWP is stopped. */
int stopped;
+ /* Non-zero if this LWP was stopped by SIGSTOP before attaching. */
+ int was_stopped;
+
/* Non-zero if this LWP will be/has been resumed. Note that an LWP
can be marked both as stopped and resumed at the same time. This
happens if we try to resume an LWP that has a wait status
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ ./gdb/testsuite/gdb.threads/attach-into-signal.c 29 Jun 2007 22:06:05 -0000
@@ -0,0 +1,70 @@
+/* This testcase is part of GDB, the GNU debugger. +/* This testcase is part of GDB, the GNU debugger.
+ +
+ Copyright 2007 Free Software Foundation, Inc. + Copyright 2007 Free Software Foundation, Inc.
@ -385,6 +419,11 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.c gdb-6.6
+ +
+ raise (SIGALRM); + raise (SIGALRM);
+ +
+ /* It is an upstream kernel bug (2.6.22-rc4-git7.x86_64, PREEMPT, SMP).
+ We never get here without ptrace(2) but we get while under ptrace(2). */
+ for (;;)
+ pause ();
+
+ abort (); + abort ();
+ /* NOTREACHED */ + /* NOTREACHED */
+ return NULL; + return NULL;
@ -407,10 +446,9 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.c gdb-6.6
+ +
+ return 0; + return 0;
+} +}
diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp gdb-6.6/gdb/testsuite/gdb.threads/attach-into-signal.exp --- /dev/null 1 Jan 1970 00:00:00 -0000
--- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp 2007-06-06 16:36:34.000000000 +0200 +++ ./gdb/testsuite/gdb.threads/attach-into-signal.exp 29 Jun 2007 22:06:06 -0000
+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-into-signal.exp 2007-06-06 13:33:11.000000000 +0200 @@ -0,0 +1,176 @@
@@ -0,0 +1,153 @@
+# Copyright 2007 +# Copyright 2007
+ +
+# This program is free software; you can redistribute it and/or modify +# This program is free software; you can redistribute it and/or modify
@ -472,12 +510,33 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp gdb-6
+ +
+ # linux-2.6.20.4.x86_64 had maximal attempt # 20 in 4 test runs. + # linux-2.6.20.4.x86_64 had maximal attempt # 20 in 4 test runs.
+ set attempts 100 + set attempts 100
+ set attempt 0 + set attempt 1
+ set passes 1 + set passes 1
+ while { $passes < 3 && $attempt < $attempts } { + while { $passes < 3 && $attempt <= $attempts } {
+ +
+ # Start with clean gdb + # Start with clean gdb
+ gdb_exit + gdb_exit
+
+ set stoppedtry 0
+ while { $stoppedtry < 10 } {
+ set fileid [open /proc/${testpid}/status r];
+ gets $fileid line1;
+ gets $fileid line2;
+ close $fileid;
+
+ if {![string match "*(stopped)*" $line2]} {
+ # No PASS message as we may be looping in multiple attempts.
+ break
+ }
+ sleep 1
+ set stoppedtry [expr $stoppedtry + 1]
+ }
+ if { $stoppedtry >= 10 } {
+ verbose -log $line2
+ set test "$threadtype: process is still running on the attempt # $attempt of $attempts"
+ break
+ }
+
+ gdb_start + gdb_start
+ gdb_reinitialize_dir $srcdir/$subdir + gdb_reinitialize_dir $srcdir/$subdir
+ gdb_load ${binfile} + gdb_load ${binfile}
@ -528,7 +587,11 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp gdb-6
+ } + }
+ } + }
+ if {$passes < 3} { + if {$passes < 3} {
+ fail $test + if {$attempt > $attempts} {
+ unresolved $test
+ } else {
+ fail $test
+ }
+ } + }
+ +
+ # Exit and detach the process. + # Exit and detach the process.
@ -555,18 +618,15 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp gdb-6
+ +
+corefunc nonthreaded +corefunc nonthreaded
+ +
+# build the test case first without threads +# build the test case also with threads
+# +#
+if { [gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug additional_flags=-DUSE_THREADS}] != "" } { +if { [gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug additional_flags=-DUSE_THREADS}] != "" } {
+ gdb_suppress_entire_file "Testcase threaded compile failed, so all tests in this file will automatically fail." + gdb_suppress_entire_file "Testcase threaded compile failed, so all tests in this file will automatically fail."
+} +}
+ +
+corefunc threaded +corefunc threaded
+ --- /dev/null 1 Jan 1970 00:00:00 -0000
+return 0 +++ ./gdb/testsuite/gdb.threads/attach-stopped.c 29 Jun 2007 22:06:06 -0000
diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.c gdb-6.6/gdb/testsuite/gdb.threads/attach-stopped.c
--- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.c 2007-06-06 16:36:34.000000000 +0200
+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-stopped.c 2007-06-06 13:33:11.000000000 +0200
@@ -0,0 +1,51 @@ @@ -0,0 +1,51 @@
+/* This testcase is part of GDB, the GNU debugger. +/* This testcase is part of GDB, the GNU debugger.
+ +
@ -619,10 +679,9 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.c gdb-6.6/gdb
+ +
+ return 0; + return 0;
+} +}
diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/gdb/testsuite/gdb.threads/attach-stopped.exp --- /dev/null 1 Jan 1970 00:00:00 -0000
--- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp 2007-06-06 16:36:34.000000000 +0200 +++ ./gdb/testsuite/gdb.threads/attach-stopped.exp 29 Jun 2007 22:06:06 -0000
+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-stopped.exp 2007-06-06 13:33:11.000000000 +0200 @@ -0,0 +1,213 @@
@@ -0,0 +1,208 @@
+# Copyright 2005-2007 +# Copyright 2005-2007
+ +
+# This program is free software; you can redistribute it and/or modify +# This program is free software; you can redistribute it and/or modify
@ -682,8 +741,10 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/g
+ # that it can be attached to. + # that it can be attached to.
+ +
+ set testpid [eval exec $binfile &] + set testpid [eval exec $binfile &]
+ exec sleep 2 +
+ + # Avoid some race:
+ sleep 2
+
+ # Stop the program + # Stop the program
+ remote_exec build "kill -s STOP ${testpid}" + remote_exec build "kill -s STOP ${testpid}"
+ +
@ -725,6 +786,9 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/g
+ +
+ gdb_exit + gdb_exit
+ +
+ # Avoid some race:
+ sleep 2
+
+ set fileid [open /proc/${testpid}/status r]; + set fileid [open /proc/${testpid}/status r];
+ gets $fileid line1; + gets $fileid line1;
+ gets $fileid line2; + gets $fileid line2;
@ -790,7 +854,7 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/g
+ gdb_exit + gdb_exit
+ +
+ # Avoid some race: + # Avoid some race:
+ exec sleep 2 + sleep 2
+ +
+ # At this point, the process should be sleeping + # At this point, the process should be sleeping
+ +
@ -831,3 +895,41 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/g
+corefunc threaded +corefunc threaded
+ +
+return 0 +return 0
--- ./gdb/doc/gdb.texinfo 1 Jul 2007 09:13:05 -0000 1.418
+++ ./gdb/doc/gdb.texinfo 1 Jul 2007 09:55:14 -0000
@@ -2167,16 +2167,29 @@ can step and continue; you can modify st
process continue running, you may use the @code{continue} command after
attaching @value{GDBN} to the process.
+For a process already being stopped before the @code{attach} command executed
+you get the informational message below. Other signals may be occasionally
+shown if they were being delivered right the time the @code{attach} command
+executed. Such process is left still stopped after the @code{detach} command
+as long as you have not used the @code{continue} command (or similiar one)
+during your debugging session.
+
+@smallexample
+Attaching to program: /bin/sleep, process 16289
+Redelivering pending Stopped (signal).
+@end smallexample
+
@table @code
@kindex detach
@item detach
When you have finished debugging the attached process, you can use the
-@code{detach} command to release it from @value{GDBN} control. Detaching
-the process continues its execution. After the @code{detach} command,
-that process and @value{GDBN} become completely independent once more, and you
-are ready to @code{attach} another process or start one with @code{run}.
-@code{detach} does not repeat if you press @key{RET} again after
-executing the command.
+@code{detach} command to release it from @value{GDBN} control. Detaching the
+process continues its execution unless it was already stopped before the
+attachment and a @code{continue} type command has not been executed. After the
+@code{detach} command, that process and @value{GDBN} become completely
+independent once more, and you are ready to @code{attach} another process or
+start one with @code{run}. @code{detach} does not repeat if you press
+@key{RET} again after executing the command.
@end table
If you exit @value{GDBN} while you have an attached process, you detach

7
gdb.spec
View File

@ -11,7 +11,7 @@ Name: gdb
Version: 6.6 Version: 6.6
# The release always contains a leading reserved number, start it at 1. # The release always contains a leading reserved number, start it at 1.
Release: 26%{?dist} Release: 27%{?dist}
License: GPL License: GPL
Group: Development/Debuggers Group: Development/Debuggers
@ -345,7 +345,7 @@ Patch251: gdb-6.5-bz237872-ppc-long-double.patch
# Avoid too long timeouts on failing cases of "annota1.exp annota3.exp". # Avoid too long timeouts on failing cases of "annota1.exp annota3.exp".
Patch254: gdb-6.6-testsuite-timeouts.patch Patch254: gdb-6.6-testsuite-timeouts.patch
# Fix attaching a stopped nonthreaded/threaded process (BZ 219118, 233852). # Fix attaching to stopped processes (BZ 219118, 233852).
# Fix attaching during a pending signal being delivered. # Fix attaching during a pending signal being delivered.
Patch256: gdb-6.6-bz233852-attach-signalled.patch Patch256: gdb-6.6-bz233852-attach-signalled.patch
@ -683,6 +683,9 @@ fi
# don't include the files in include, they are part of binutils # don't include the files in include, they are part of binutils
%changelog %changelog
* Sun Sep 16 2007 Jan Kratochvil <jan.kratochvil@redhat.com> - 6.6-27
- Fix attaching to stopped processes and/or pending signals.
* Tue Aug 28 2007 Jan Kratochvil <jan.kratochvil@redhat.com> - 6.6-26 * Tue Aug 28 2007 Jan Kratochvil <jan.kratochvil@redhat.com> - 6.6-26
- New fast verification whether the .debug file matches its peer (build-id). - New fast verification whether the .debug file matches its peer (build-id).
- New locating of the matching binaries from the pure core file (build-id). - New locating of the matching binaries from the pure core file (build-id).