6 files changed, 57 insertions, 32 deletions
diff --git a/lib/libc/sys/Symbol.map b/lib/libc/sys/Symbol.map
index c1532ac..46b0749 100644
--- a/lib/libc/sys/Symbol.map
+++ b/lib/libc/sys/Symbol.map
@@ -34,9 +34,7 @@ FBSD_1.0 {
 	__setugid;
 	__syscall;
 	__sysctl;
-	_umtx_lock;
 	_umtx_op;
-	_umtx_unlock;
 	abort2;
 	accept;
 	access;
@@ -455,12 +453,8 @@ FBSDprivate_1.0 {
 	__sys___syscall;
 	___sysctl;
 	__sys___sysctl;
-	__umtx_lock;
-	__sys__umtx_lock;
 	__umtx_op;
 	__sys__umtx_op;
-	__umtx_unlock;
-	__sys__umtx_unlock;
 	_abort2;
 	__sys_abort2;
 	_accept;
diff --git a/lib/libc/sys/aio_fsync.2 b/lib/libc/sys/aio_fsync.2
index 52b47efb..9d5d143 100644
--- a/lib/libc/sys/aio_fsync.2
+++ b/lib/libc/sys/aio_fsync.2
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 21, 2016
+.Dd August 19, 2016
 .Dt AIO_FSYNC 2
 .Os
 .Sh NAME
@@ -74,16 +74,14 @@ the call returns without having enqueued the request.
 .Pp
 The
 .Fa iocb->aio_sigevent
-structure can be used to request notification of the request's
+structure can be used to request notification of the operation's
 completion as described in
 .Xr aio 4 .
 .Sh RESTRICTIONS
-The asynchronous I/O Control Block structure pointed to by
+The Asynchronous I/O Control Block structure pointed to by
 .Fa iocb
 must remain valid until the
 operation has completed.
-For this reason, use of auto (stack) variables
-for these objects is discouraged.
 .Pp
 The asynchronous I/O control buffer
 .Fa iocb
@@ -91,9 +89,8 @@ should be zeroed before the
 .Fn aio_fsync
 call to avoid passing bogus context information to the kernel.
 .Pp
-Modifications of the Asynchronous I/O Control Block structure or the
-buffer contents after the request has been enqueued, but before the
-request has completed, are not allowed.
+Modification of the Asynchronous I/O Control Block structure is not allowed
+while the request is queued.
 .Sh RETURN VALUES
 .Rv -std aio_fsync
 .Sh ERRORS
diff --git a/lib/libc/sys/aio_mlock.2 b/lib/libc/sys/aio_mlock.2
index cc588b5..f7f4a27 100644
--- a/lib/libc/sys/aio_mlock.2
+++ b/lib/libc/sys/aio_mlock.2
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 21, 2016
+.Dd August 19, 2016
 .Dt AIO_MLOCK 2
 .Os
 .Sh NAME
@@ -67,7 +67,7 @@ then the call returns without having enqueued the request.
 .Pp
 The
 .Fa iocb->aio_sigevent
-structure can be used to request notification of the request's
+structure can be used to request notification of the operation's
 completion as described in
 .Xr aio 4 .
 .Sh RESTRICTIONS
@@ -77,8 +77,6 @@ and the buffer that the
 .Fa iocb->aio_buf
 member of that structure references must remain valid until the
 operation has completed.
-For this reason, use of auto (stack) variables
-for these objects is discouraged.
 .Pp
 The asynchronous I/O control buffer
 .Fa iocb
@@ -87,8 +85,8 @@ should be zeroed before the
 call to avoid passing bogus context information to the kernel.
 .Pp
 Modifications of the Asynchronous I/O Control Block structure or the
-buffer contents after the request has been enqueued, but before the
-request has completed, are not allowed.
+memory mapping described by the virtual address range are not allowed
+while the request is queued.
 .Sh RETURN VALUES
 .Rv -std aio_mlock
 .Sh ERRORS
diff --git a/lib/libc/sys/aio_read.2 b/lib/libc/sys/aio_read.2
index 2f16809..bbf96cc 100644
--- a/lib/libc/sys/aio_read.2
+++ b/lib/libc/sys/aio_read.2
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 21, 2016
+.Dd August 19, 2016
 .Dt AIO_READ 2
 .Os
 .Sh NAME
@@ -82,7 +82,7 @@ not be referenced after the request is enqueued.
 .Pp
 The
 .Fa iocb->aio_sigevent
-structure can be used to request notification of the request's
+structure can be used to request notification of the operation's
 completion as described in
 .Xr aio 4 .
 .Sh RESTRICTIONS
@@ -92,8 +92,6 @@ and the buffer that the
 .Fa iocb->aio_buf
 member of that structure references must remain valid until the
 operation has completed.
-For this reason, use of auto (stack) variables
-for these objects is discouraged.
 .Pp
 The asynchronous I/O control buffer
 .Fa iocb
@@ -102,8 +100,7 @@ should be zeroed before the
 call to avoid passing bogus context information to the kernel.
 .Pp
 Modifications of the Asynchronous I/O Control Block structure or the
-buffer contents after the request has been enqueued, but before the
-request has completed, are not allowed.
+buffer contents are not allowed while the request is queued.
 .Pp
 If the file offset in
 .Fa iocb->aio_offset
diff --git a/lib/libc/sys/aio_write.2 b/lib/libc/sys/aio_write.2
index 414f98f..a3268e5 100644
--- a/lib/libc/sys/aio_write.2
+++ b/lib/libc/sys/aio_write.2
@@ -24,7 +24,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd July 21, 2016
+.Dd August 19, 2016
 .Dt AIO_WRITE 2
 .Os
 .Sh NAME
@@ -88,7 +88,7 @@ be referenced after the request is enqueued.
 .Pp
 The
 .Fa iocb->aio_sigevent
-structure can be used to request notification of the request's
+structure can be used to request notification of the operation's
 completion as described in
 .Xr aio 4 .
 .Sh RESTRICTIONS
@@ -98,8 +98,6 @@ and the buffer that the
 .Fa iocb->aio_buf
 member of that structure references must remain valid until the
 operation has completed.
-For this reason, use of auto (stack) variables
-for these objects is discouraged.
 .Pp
 The asynchronous I/O control buffer
 .Fa iocb
@@ -108,8 +106,7 @@ should be zeroed before the
 system call to avoid passing bogus context information to the kernel.
 .Pp
 Modifications of the Asynchronous I/O Control Block structure or the
-buffer contents after the request has been enqueued, but before the
-request has completed, are not allowed.
+buffer contents are not allowed while the request is queued.
 .Pp
 If the file offset in
 .Fa iocb->aio_offset
diff --git a/lib/libc/sys/ptrace.2 b/lib/libc/sys/ptrace.2
index 14ce6dd..74798d2 100644
--- a/lib/libc/sys/ptrace.2
+++ b/lib/libc/sys/ptrace.2
@@ -151,6 +151,11 @@ The process ID of the new child process will also be present in the
 .Va pl_child_pid
 member of
 .Vt "struct ptrace_lwpinfo" .
+If the new child process was created via
+.Xr vfork 2 ,
+the traced process's stop will also include the
+.Dv PL_FLAG_VFORKED
+flag.
 Note that new child processes will be attached with the default
 tracing event mask;
 they do not inherit the event mask of the traced process.
@@ -173,6 +178,33 @@ Note that new processes do not report an event for the creation of their
 initial thread,
 and exiting processes do not report an event for the termination of the
 last thread.
+.It Dv PTRACE_VFORK
+Report a stop event when a parent process resumes after a
+.Xr vfork 2 .
+.Pp
+When a thread in the traced process creates a new child process via
+.Xr vfork 2 ,
+the stop that reports
+.Dv PL_FLAG_FORKED
+and
+.Dv PL_FLAG_SCX
+occurs just after the child process is created,
+but before the thread waits for the child process to stop sharing process
+memory.
+If a debugger is not tracing the new child process,
+it must ensure that no breakpoints are enabled in the shared process
+memory before detaching from the new child process.
+This means that no breakpoints are enabled in the parent process either.
+.Pp
+The
+.Dv PTRACE_VFORK
+flag enables a new stop that indicates when the new child process stops
+sharing the process memory of the parent process.
+A debugger can reinsert breakpoints in the parent process and resume it
+in response to this event.
+This event is indicated by setting the
+.Dv PL_FLAG_VFORK_DONE
+flag.
 .El
 .Pp
 The default tracing event mask when attaching to a process via
@@ -501,6 +533,16 @@ is enabled.
 Note that this event is not reported when the last LWP in a process exits.
 The termination of the last thread is reported via a normal process exit
 event.
+.It PL_FLAG_VFORKED
+Indicates that the thread is returning from a call to
+.Xr vfork 2
+that created a new child process.
+This flag is set in addition to
+.Dv PL_FLAG_FORKED .
+.It PL_FLAG_VFORK_DONE
+Indicates that the thread has resumed after a child process created via
+.Xr vfork 2
+has stopped sharing its address space with the traced process.
 .El
 .It pl_sigmask
 The current signal mask of the LWP