scftorture: Count single_rpc offline failures in statistics outputgrafted

scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop.  As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.

Add the missing accumulation so that the printed value reflects the
actual counts.

Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>

1 files changed, 129 insertions, 0 deletions

diff --git a/Documentation/usb/authorization.rst b/Documentation/usb/authorization.rst
new file mode 100644
index 000000000..150a14970
--- /dev/null
+++ b/Documentation/usb/authorization.rst
@@ -0,0 +1,129 @@
+==============================================================
+Authorizing (or not) your USB devices to connect to the system
+==============================================================
+
+Copyright (C) 2007 Inaky Perez-Gonzalez <inaky@linux.intel.com> Intel Corporation
+
+This feature allows you to control if a USB device can be used (or
+not) in a system. This feature will allow you to implement a lock-down
+of USB devices, fully controlled by user space.
+
+As of now, when a USB device is connected it is configured and
+its interfaces are immediately made available to the users.  With this
+modification, only if root authorizes the device to be configured will
+then it be possible to use it.
+
+Usage
+=====
+
+Authorize a device to connect::
+
+	$ echo 1 > /sys/bus/usb/devices/DEVICE/authorized
+
+De-authorize a device::
+
+	$ echo 0 > /sys/bus/usb/devices/DEVICE/authorized
+
+Set new devices connected to hostX to be deauthorized by default (ie:
+lock down)::
+
+	$ echo 0 > /sys/bus/usb/devices/usbX/authorized_default
+
+Remove the lock down::
+
+	$ echo 1 > /sys/bus/usb/devices/usbX/authorized_default
+
+By default, all USB devices are authorized.  Writing "2" to the
+authorized_default attribute causes the kernel to authorize by default
+only devices connected to internal USB ports.
+
+
+Example system lockdown (lame)
+------------------------------
+
+Imagine you want to implement a lockdown so only devices of type XYZ
+can be connected (for example, it is a kiosk machine with a visible
+USB port)::
+
+  boot up
+  rc.local ->
+
+   for host in /sys/bus/usb/devices/usb*
+   do
+      echo 0 > $host/authorized_default
+   done
+
+Hookup an script to udev, for new USB devices::
+
+ if device_is_my_type $DEV
+ then
+   echo 1 > $device_path/authorized
+ done
+
+
+Now, device_is_my_type() is where the juice for a lockdown is. Just
+checking if the class, type and protocol match something is the worse
+security verification you can make (or the best, for someone willing
+to break it). If you need something secure, use crypto and Certificate
+Authentication or stuff like that. Something simple for an storage key
+could be::
+
+ function device_is_my_type()
+ {
+   echo 1 > authorized		# temporarily authorize it
+                                # FIXME: make sure none can mount it
+   mount DEVICENODE /mntpoint
+   sum=$(md5sum /mntpoint/.signature)
+   if [ $sum = $(cat /etc/lockdown/keysum) ]
+   then
+        echo "We are good, connected"
+        umount /mntpoint
+        # Other stuff so others can use it
+   else
+        echo 0 > authorized
+   fi
+ }
+
+
+Of course, this is lame, you'd want to do a real certificate
+verification stuff with PKI, so you don't depend on a shared secret,
+etc, but you get the idea. Anybody with access to a device gadget kit
+can fake descriptors and device info. Don't trust that. You are
+welcome.
+
+
+Interface authorization
+-----------------------
+
+There is a similar approach to allow or deny specific USB interfaces.
+That allows to block only a subset of an USB device.
+
+Authorize an interface::
+
+	$ echo 1 > /sys/bus/usb/devices/INTERFACE/authorized
+
+Deauthorize an interface::
+
+	$ echo 0 > /sys/bus/usb/devices/INTERFACE/authorized
+
+The default value for new interfaces
+on a particular USB bus can be changed, too.
+
+Allow interfaces per default::
+
+	$ echo 1 > /sys/bus/usb/devices/usbX/interface_authorized_default
+
+Deny interfaces per default::
+
+	$ echo 0 > /sys/bus/usb/devices/usbX/interface_authorized_default
+
+Per default the interface_authorized_default bit is 1.
+So all interfaces would authorized per default.
+
+Note:
+  If a deauthorized interface will be authorized so the driver probing must
+  be triggered manually by writing INTERFACE to /sys/bus/usb/drivers_probe
+
+For drivers that need multiple interfaces all needed interfaces should be
+authorized first. After that the drivers should be probed.
+This avoids side effects.