From 41705867ade3babe53581cd42141eaa46a554eb8 Mon Sep 17 00:00:00 2001 From: Jan Kratochvil Date: Sun, 16 Sep 2007 22:34:35 +0000 Subject: [PATCH] - Fix attaching to stopped processes and/or pending signals. --- gdb-6.6-bz233852-attach-signalled.patch | 684 ++++++++++++++---------- gdb.spec | 7 +- 2 files changed, 398 insertions(+), 293 deletions(-) diff --git a/gdb-6.6-bz233852-attach-signalled.patch b/gdb-6.6-bz233852-attach-signalled.patch index 86b1854..70de6b7 100644 --- a/gdb-6.6-bz233852-attach-signalled.patch +++ b/gdb-6.6-bz233852-attach-signalled.patch @@ -1,271 +1,117 @@ -diff -u -rup gdb-6.6-orig/gdb/inf-ptrace.c gdb-6.6/gdb/inf-ptrace.c ---- 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 -@@ -38,6 +38,9 @@ +2007-07-01 Jan Kratochvil + + * linux-nat.h (struct lwp_info): New field WAS_STOPPED. + * 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 + + * 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 + + * 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. */ - static struct target_ops *ptrace_ops_hack; ++* On GNU/Linux, stopped processes may get attached to now. Signals being ++delivered at the time of the attach command no longer get lost. + -+/* Stored PID of the process being stopped during attach. */ -+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) + * New commands + 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 --/* Detach from the inferior, optionally passing it the signal -- specified by ARGS. If FROM_TTY is non-zero, be chatty about it. */ -+/* 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; ++#define STRINGIFY_ARG(x) #x ++#define STRINGIFY(x) STRINGIFY_ARG (x) + -+ if (args) -+ error (_("Too many arguments")); - - 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; ++static int linux_ptrace_post_attach (struct lwp_info *lp); ++static int kill_lwp (int lwpid, int signo); + - 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 -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; +- pid_t pid; int status; -+ unsigned long sig; if (ptrace (PTRACE_ATTACH, GET_LWP (ptid), 0, 0) < 0) - { -@@ -1015,32 +1016,54 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver - "LLAL: PTRACE_ATTACH %s, 0, 0 (OK)\n", - target_pid_to_str (ptid)); +@@ -1002,45 +1012,23 @@ lin_lwp_attach_lwp (ptid_t ptid, int ver + creation is interrupted; as of Linux 2.6.19, a kernel + bug may place threads in the thread list and then fail + 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); - if (pid == -1 && errno == ECHILD) -+ sig = SIGSTOP; -+ do - { +- { - /* Try again with __WCLONE to check cloned processes. */ - pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE); -+ if (sig != SIGSTOP) -+ 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) +- if (pid == -1 && errno == ECHILD) - 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; -- } -+ { -+ /* Try again with __WCLONE to check cloned processes. */ -+ pid = my_waitpid (GET_LWP (ptid), &status, __WCLONE); -+ if (pid == -1 && errno == ECHILD) -+ 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)); ++ status = linux_ptrace_post_attach (lp); ++ if (status != 0) ++ { ++ error (_("Thread %s exited: %s"), target_pid_to_str (ptid), ++ status_to_str (status)); + } - gdb_assert (pid == GET_LWP (ptid) - && WIFSTOPPED (status) && WSTOPSIG (status)); -+ 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)) -+ { -+ 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); +- +- target_post_attach (pid); ++ target_post_attach (GET_LWP (ptid)); 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 { -@@ -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) { struct lwp_info *lp; - pid_t pid; -- int status; + int status; /* FIXME: We should probably accept a list of process id's, and - attach all of them. */ -@@ -1076,22 +1097,6 @@ linux_nat_attach (char *args, int from_t +@@ -1076,21 +1225,12 @@ linux_nat_attach (char *args, int from_t inferior_ptid = BUILD_LWP (GET_PID (inferior_ptid), GET_PID (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) - && 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; - /* Fake the SIGSTOP that core GDB expects. */ -@@ -1099,8 +1104,8 @@ linux_nat_attach (char *args, int from_t +@@ -1099,8 +1239,8 @@ linux_nat_attach (char *args, int from_t lp->resumed = 1; 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 ---- 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. */ +@@ -1173,6 +1313,9 @@ linux_nat_detach (char *args, int from_t - #define target_attach(args, from_tty) \ - (*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 ---- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.c 2007-06-06 16:36:34.000000000 +0200 -+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-into-signal.c 2007-06-06 13:33:11.000000000 +0200 -@@ -0,0 +1,65 @@ + trap_ptid = null_ptid; + ++ if (lwp_list->was_stopped) ++ args = STRINGIFY (SIGSTOP); ++ + /* 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. + + 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); + ++ /* 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 (); + /* NOTREACHED */ + 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; +} -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 ---- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp 2007-06-06 16:36:34.000000000 +0200 -+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-into-signal.exp 2007-06-06 13:33:11.000000000 +0200 -@@ -0,0 +1,153 @@ +--- /dev/null 1 Jan 1970 00:00:00 -0000 ++++ ./gdb/testsuite/gdb.threads/attach-into-signal.exp 29 Jun 2007 22:06:06 -0000 +@@ -0,0 +1,176 @@ +# Copyright 2007 + +# 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. + set attempts 100 -+ set attempt 0 ++ set attempt 1 + set passes 1 -+ while { $passes < 3 && $attempt < $attempts } { ++ while { $passes < 3 && $attempt <= $attempts } { + + # Start with clean gdb + 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_reinitialize_dir $srcdir/$subdir + 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} { -+ fail $test ++ if {$attempt > $attempts} { ++ unresolved $test ++ } else { ++ fail $test ++ } + } + + # Exit and detach the process. @@ -555,18 +618,15 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-into-signal.exp gdb-6 + +corefunc nonthreaded + -+# build the test case first without threads ++# build the test case also with threads +# +if { [gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" executable {debug additional_flags=-DUSE_THREADS}] != "" } { + gdb_suppress_entire_file "Testcase threaded compile failed, so all tests in this file will automatically fail." +} + +corefunc threaded -+ -+return 0 -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 +--- /dev/null 1 Jan 1970 00:00:00 -0000 ++++ ./gdb/testsuite/gdb.threads/attach-stopped.c 29 Jun 2007 22:06:06 -0000 @@ -0,0 +1,51 @@ +/* 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; +} -diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/gdb/testsuite/gdb.threads/attach-stopped.exp ---- gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp 2007-06-06 16:36:34.000000000 +0200 -+++ gdb-6.6/gdb/testsuite/gdb.threads/attach-stopped.exp 2007-06-06 13:33:11.000000000 +0200 -@@ -0,0 +1,208 @@ +--- /dev/null 1 Jan 1970 00:00:00 -0000 ++++ ./gdb/testsuite/gdb.threads/attach-stopped.exp 29 Jun 2007 22:06:06 -0000 +@@ -0,0 +1,213 @@ +# Copyright 2005-2007 + +# 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. + + set testpid [eval exec $binfile &] -+ exec sleep 2 -+ ++ ++ # Avoid some race: ++ sleep 2 ++ + # Stop the program + remote_exec build "kill -s STOP ${testpid}" + @@ -725,6 +786,9 @@ diff -u -rup gdb-6.6-orig/gdb/testsuite/gdb.threads/attach-stopped.exp gdb-6.6/g + + gdb_exit + ++ # Avoid some race: ++ sleep 2 ++ + set fileid [open /proc/${testpid}/status r]; + gets $fileid line1; + 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 + + # Avoid some race: -+ exec sleep 2 ++ sleep 2 + + # 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 + +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 diff --git a/gdb.spec b/gdb.spec index f86ea76..31bda1c 100644 --- a/gdb.spec +++ b/gdb.spec @@ -11,7 +11,7 @@ Name: gdb Version: 6.6 # The release always contains a leading reserved number, start it at 1. -Release: 26%{?dist} +Release: 27%{?dist} License: GPL 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". 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. 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 %changelog +* Sun Sep 16 2007 Jan Kratochvil - 6.6-27 +- Fix attaching to stopped processes and/or pending signals. + * Tue Aug 28 2007 Jan Kratochvil - 6.6-26 - 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).