diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index f4bfe7851e3..04754ac2ef1 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,13 @@
+2018-04-11  Pedro Alves  <palves@redhat.com>
+
+	* target.c (fileio_fh_t::t): Add comment.
+	(target_fileio_pwrite, target_fileio_pread, target_fileio_fstat)
+	(target_fileio_close): Handle a NULL target.
+	(invalidate_fileio_fh): New.
+	(target_close): Call it.
+	* remote.c (remote_hostio_send_command): No longer check whether
+	remote_desc is open.
+
 2018-04-11  Pedro Alves  <palves@redhat.com>
 
 	* target.c (fileio_fh_t): Make it a named struct instead of a
diff --git a/gdb/remote.c b/gdb/remote.c
index a46f1f8ddbe..f54a38833b3 100644
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -11350,8 +11350,7 @@ remote_hostio_send_command (int command_bytes, int which_packet,
   int ret, bytes_read;
   char *attachment_tmp;
 
-  if (!rs->remote_desc
-      || packet_support (which_packet) == PACKET_DISABLE)
+  if (packet_support (which_packet) == PACKET_DISABLE)
     {
       *remote_errno = FILEIO_ENOSYS;
       return -1;
diff --git a/gdb/target.c b/gdb/target.c
index eec4e58d384..e8d4ae7ea8e 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -2793,7 +2793,8 @@ default_fileio_target (void)
 
 struct fileio_fh_t
 {
-  /* The target on which this file is open.  */
+  /* The target on which this file is open.  NULL if the target is
+     meanwhile closed while the handle is open.  */
   target_ops *target;
 
   /* The file descriptor on the target.  */
@@ -2818,6 +2819,20 @@ static std::vector<fileio_fh_t> fileio_fhandles;
    list each time a new file is opened.  */
 static int lowest_closed_fd;
 
+/* Invalidate the target associated with open handles that were open
+   on target TARG, since we're about to close (and maybe destroy) the
+   target.  The handles remain open from the client's perspective, but
+   trying to do anything with them other than closing them will fail
+   with EIO.  */
+
+static void
+fileio_handles_invalidate_target (target_ops *targ)
+{
+  for (fileio_fh_t &fh : fileio_fhandles)
+    if (fh.target == targ)
+      fh.target = NULL;
+}
+
 /* Acquire a target fileio file descriptor.  */
 
 static int
@@ -2933,6 +2948,8 @@ target_fileio_pwrite (int fd, const gdb_byte *write_buf, int len,
 
   if (fh->is_closed ())
     *target_errno = EBADF;
+  else if (fh->target == NULL)
+    *target_errno = EIO;
   else
     ret = fh->target->to_fileio_pwrite (fh->target, fh->target_fd, write_buf,
 					len, offset, target_errno);
@@ -2957,6 +2974,8 @@ target_fileio_pread (int fd, gdb_byte *read_buf, int len,
 
   if (fh->is_closed ())
     *target_errno = EBADF;
+  else if (fh->target == NULL)
+    *target_errno = EIO;
   else
     ret = fh->target->to_fileio_pread (fh->target, fh->target_fd, read_buf,
 				       len, offset, target_errno);
@@ -2980,6 +2999,8 @@ target_fileio_fstat (int fd, struct stat *sb, int *target_errno)
 
   if (fh->is_closed ())
     *target_errno = EBADF;
+  else if (fh->target == NULL)
+    *target_errno = EIO;
   else
     ret = fh->target->to_fileio_fstat (fh->target, fh->target_fd,
 				       sb, target_errno);
@@ -3003,8 +3024,11 @@ target_fileio_close (int fd, int *target_errno)
     *target_errno = EBADF;
   else
     {
-      ret = fh->target->to_fileio_close (fh->target, fh->target_fd,
-					 target_errno);
+      if (fh->target != NULL)
+	ret = fh->target->to_fileio_close (fh->target, fh->target_fd,
+					   target_errno);
+      else
+	ret = 0;
       release_fileio_fd (fd, fh);
     }
 
@@ -3390,6 +3414,8 @@ target_close (struct target_ops *targ)
 {
   gdb_assert (!target_is_pushed (targ));
 
+  fileio_handles_invalidate_target (targ);
+
   if (targ->to_xclose != NULL)
     targ->to_xclose (targ);
   else if (targ->to_close != NULL)