5 files changed, 140 insertions, 1 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index bcf1de9..534e9ff 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,11 @@
 2019-10-03  Andrew Burgess  <andrew.burgess@embecosm.com>
 
+	* linux-nat.c (linux_nat_filter_event): Don't ignore SIGSTOP if we
+	have just sent the thread a SIGSTOP and are waiting for it to
+	arrive.
+
+2019-10-03  Andrew Burgess  <andrew.burgess@embecosm.com>
+
 	* btrace.c (btrace_add_pc): Remove whitespace before the template
 	parameter in 'std::vector <...>'.
 	(parse_xml_btrace_block): Likewise.
diff --git a/gdb/linux-nat.c b/gdb/linux-nat.c
index cd5cf18..0a8ea5b 100644
--- a/gdb/linux-nat.c
+++ b/gdb/linux-nat.c
@@ -3146,9 +3146,12 @@ linux_nat_filter_event (int lwpid, int status)
 
       /* When using hardware single-step, we need to report every signal.
 	 Otherwise, signals in pass_mask may be short-circuited
-	 except signals that might be caused by a breakpoint.  */
+	 except signals that might be caused by a breakpoint, or SIGSTOP
+	 if we sent the SIGSTOP and are waiting for it to arrive.  */
       if (!lp->step
 	  && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status))
+	  && (WSTOPSIG (status) != SIGSTOP
+	      || !find_thread_ptid (lp->ptid)->stop_requested)
 	  && !linux_wstatus_maybe_breakpoint (status))
 	{
 	  linux_resume_one_lwp (lp, lp->step, signo);
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index acc930a..867db05 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-10-03  Andrew Burgess  <andrew.burgess@embecosm.com>
+
+	* gdb.threads/stop-with-handle.c: New file.
+	* gdb.threads/stop-with-handle.exp: New file.
+
 2019-10-03  Tom de Vries  <tdevries@suse.de>
 
 	PR testsuite/25059
diff --git a/gdb/testsuite/gdb.threads/stop-with-handle.c b/gdb/testsuite/gdb.threads/stop-with-handle.c
new file mode 100644
index 0000000..335676b
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/stop-with-handle.c
@@ -0,0 +1,74 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2019 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <stdio.h>
+#include <pthread.h>
+#include <unistd.h>
+
+/* A place to record the thread.  */
+pthread_t the_thread;
+
+/* The worker thread just spins forever.  */
+void*
+thread_worker (void *payload)
+{
+  while (1)
+    {
+      sleep (1);
+    }
+
+  return NULL;
+}
+
+/* Create a worker thread.  */
+int
+spawn_thread ()
+{
+  if (pthread_create (&the_thread, NULL, thread_worker, NULL))
+    {
+      fprintf (stderr, "Unable to create thread.\n");
+      return 0;
+    }
+  return 1;
+}
+
+/* A place for GDB to place a breakpoint.   */
+void __attribute__((used))
+breakpt ()
+{
+  /* Nothing.  */
+}
+
+/* Create a worker thread that just spins forever, then enter a loop
+   periodically calling the BREAKPT function.  */
+int
+main()
+{
+  /* Ensure we stop if GDB crashes and DejaGNU fails to kill us.  */
+  alarm (10);
+
+  spawn_thread ();
+
+  while (1)
+    {
+      sleep (1);
+
+      breakpt ();
+    }
+
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.threads/stop-with-handle.exp b/gdb/testsuite/gdb.threads/stop-with-handle.exp
new file mode 100644
index 0000000..ad69ec1
--- /dev/null
+++ b/gdb/testsuite/gdb.threads/stop-with-handle.exp
@@ -0,0 +1,51 @@
+# Copyright 2019 Free Software Foundation, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# This test covers a case where SIGSTOP has been configured to be
+# passed to the target with GDB's 'handle' command, and then a
+# multi-threaded inferior encounters an event that causes all theads
+# to be stopped.
+#
+# The problem that (used) to exist was that GDB would see the SIGSTOP,
+# but decide to ignore the signal based on the handle table.
+
+standard_testfile
+
+if {[prepare_for_testing "failed to prepare" \
+	 "${testfile}" "${srcfile}" {debug pthreads}]} {
+    return -1
+}
+
+if ![runto_main] then {
+    fail "can't run to main"
+    return 0
+}
+
+# Have SIGSTOP sent to the inferior.
+gdb_test "handle SIGSTOP nostop noprint pass" \
+    [multi_line \
+	 "Signal\[ \t\]+Stop\[ \t\]+Print\[ \t\]+Pass to program\[ \t\]+Description" \
+	 "SIGSTOP\[ \t\]+No\[ \t\]+No\[ \t\]+Yes\[ \t\]+Stopped \\(signal\\)"]
+
+# Create a breakpoint, and when we hit it automatically finish the
+# current frame.
+gdb_breakpoint breakpt
+
+# When the bug triggers this continue never completes.  GDB hits the
+# breakpoint in thread 1, and then tries to stop the second thread by
+# sending it SIGSTOP.  GDB sees the SIGSTOP arrive in thread 2 but
+# incorrect decides to pass the SIGSTOP to the thread rather than
+# bringing the thread to a stop.
+gdb_continue_to_breakpoint breakpt