Commit Graph
25 Commits
Author SHA1 Message Date
Wei Liu e6a8fe423e docs: document ~/control/sysrq
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
2018-09-11 08:54:22 +01:00
Stefano Stabellini 6bbcb226ce xl/libxl: add pvcalls support
Add pvcalls support to libxl and xl. Create the appropriate pvcalls
entries in xenstore.

Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2018-03-30 12:51:55 +01:00
Vivek Kumar Chaubey cd3ed39b9d hvmloader: support system enclosure asset tag (SMBIOS type 3)
Allow setting system enclosure asset tag for HVM guest. Guest OS can
check and perform desired operation like support installation.
Also added documentation of '~/bios-string/*' xenstore keys into
docs/misc/xenstore-paths.markdown

Signed-off-by: Vivek Kumar Chaubey <vivekkumar.chaubey@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
2017-08-21 15:49:36 +02:00
Paul Durrant 3bdb14004b docs/misc: document PV control/feature keys for laptop/slate mode
Commit 4c8153d9 "add ACPI device for Windows laptop/slate mode switch"
added code to provide an 'laptop/slate mode' ACPI device to guests.

When present this device is used by Microsoft Windows to bind a HID
driver which controls whether the Windows desktop appearance is optimized
for laptop/desktop or slate/tablet PCs. The mechanism for switching
between modes is to open a handle to this driver and write a byte of
arbitrary data.

This patch documents xenstore keys such that a PV agent running in a
Windows guest can advertise the capability to, and receive instruction
from, a toolstack to cause such a mode switch.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2017-03-30 16:55:21 +01:00
Paul Durrant f6abad1683 docs/misc: document platform/acpi_laptop_slate key
Commit 4c8153d9 "add ACPI device for Windows laptop/slate mode switch"
added code that makes use of a new xenstore guest platform key called
'acpi_laptop_slate'. This path needs to be added to the documentation.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2017-03-30 15:42:12 +01:00
Ian Jackson 91fbfc37f5 libxl: Document ~/serial/ correctly
xenstore-paths.markdown talked about ~/device/serial/, but that's not
used.

(It is very wrong for this value, which contains a driver domain
filesystem path, to be in the guest's area of xenstore.  However, it
is only ever created by libxl and ready by xenconsoled.  When it is
created, it inherits the read-only permissions of /local/domain/DOMID.
So there is no security bug.)

This is a followup to XSA-175.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Release-acked-by: Wei Liu <wei.liu2@citrix.com>
2016-06-02 16:35:08 +01:00
Ian Jackson deffd3cc8a libxl: Make copy of every xs backend in /libxl in _generic_add
We want to stop libxl trustingly reading information from the backend
directory (since this is, of course, writeable by the backend, which
might be a semi-trusted driver domain).

In principle it is wrong in current libxl for anything to try to
divine virtual device configuration from xenstore: the JSON domain
config ought to supply that, and xenstore should only tell us which
devices actually exist.

However:

Firstly, there are several existing places where configuration
information is retrieved from xenstore rather than JSON.  We do not
want to reen gineer this in a security patch.

Secondly, we want to make a security patch which can be backported to
versions of libxl without the JSON configuration machinery.

So we take the expedient approach of keeping a copy of the
configuration somewhere we trust, namely /libxl.  This is obviously
fairly low-risk, although it does write significantly more keys in
xenstore.

In this patch we make this change in libxl__device_generic_add.  This
is responsible for actually writing the vast majority of device
information to xenstore.  There are a few loose ends which will be
dealt with in a moment.

Likewise, changes to readers to use the new location will appear in
further patches.

This is part of XSA-178.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
2016-06-02 15:53:28 +01:00
Ian Jackson 811b188add libxl: Record backend/frontend paths in /libxl/$DOMID
This gives us a record of all the backends we have set up for a
domain, which is separate from the frontends in
  /local/domain/$DOMID/device.

In particular:

1. A guest has write permission for the frontend path:
  /local/domain/$DOMID/device/$KIND/$DEVID
which means that the guest can completely delete the frontend.
(They can't recreate it because they don't have write permission
on the containing directory.)

2. A guest has write permission for the backend path recorded in the
frontend, ie, it can write to
  /local/domain/$DOMID/device/$KIND/$DEVID/backend
which means that the guest can break the association between
frontend and backend.

So we can't rely on iterating over the frontends to find all the
backends, or examining a frontend to discover how a device is
configured.

So, have libxl__device_generic_add record the frontend and backend
paths in /libxl/$DOMID/device, and have libxl__device_destroy remove
them again.

Create the containing directory /libxl/GUEST/device in
libxl__domain_make.  The already existing xs_rm in devices_destroy_cb
will take care of removing it.

This is part of XSA-175.

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
---
v2: Correct actual path computation (!)
v3: Correct actual path computation - really this time (!)
2016-06-02 15:53:28 +01:00
Juergen Gross 043910384c libxl: add new pvusb backend "qusb" provided by qemu
Add a new pvusb backend type "qusb" which is provided by qemu. It can
be selected either by specifying the type directly in the configuration
or it is selected automatically by libxl in case there is no "usbback"
driver loaded.

The "qusb" backend is a full replacement for the kernel based backend
"vusb". The interface to the frontend is the very same including all
Xenstore paths, while the backend paths in Xenstore differ ("qusb"
instead ov "vusb").

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-04-06 14:58:02 +01:00
Juergen Gross c5add99428 libxl: add query function for backend support by device model
Add a function to query whether the device model is supporting a
specific backend type. The device model is writing the supported
backend types to Xenstore on startup. The new query function checks
for the appropriate entry to be present.

As not all versions of qemu are capable to indicate support of
specific backends the query function is to be called with an indicator
whether the default return value should be "supported" (in case qemu
doesn't know set any support information) or "not supported".

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-04-06 14:58:02 +01:00
Juergen Gross 80428e8510 doc: document pvusb Xenstore paths
The patches adding Xen tools support for paravirtualized USB devices
(pvUSB) omitted documenting the introduced Xenstore paths.

Add the paths to docs/misc/xenstore-paths.markdown

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2016-04-01 15:53:17 +01:00
Juergen Gross 9bec5237f0 doc: correct hyperlinks in docs/misc/xenstore-paths.markdown
The hyperlinks for the different I/O protocols are wrong.

Correct them.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2016-04-01 15:52:32 +01:00
Olaf Hering 1e9cce9586 docs: add vscsi to xenstore-paths.markdown
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
2016-03-23 11:03:57 +01:00
Juergen Gross 1f58f295f3 docs: document xenstore domain xenstore paths
Add the xenstore domain specific xenstore paths to
docs/misc/xenstore-paths.markdown

Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2016-01-18 16:36:08 +00:00
Paul Durrant 26b4f4da89 docs: Introduce xenstore paths for guest network address information
It is useful for a toolstack to be able to see the network addresses
in use by a domain for a particular vif in xenstore for display
purposes and, for example, so that a VNC session can be established
to the guest GUI.

This patch documents paths to allow a domain to advertise an interface
name, MAC (unicast and multicast) and IP (version 4 and 6) address
information.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2015-11-24 16:19:00 +00:00
Paul Durrant e8f98cb2d4 docs: Introduce xenstore paths for hotplug features
Without some indication from a guest it is not possible for a
toolstack to know whether instantiation of a new vbd or vif should
result in a new PV device of the appropriate type being brought online.
(In other words whether guest PV drivers are present and functioning).

This patch documents two paths which vif and vbd frontend drivers can
use to advertise their ability to respond to new vif or vbd
instantiations.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2015-11-24 16:19:00 +00:00
Paul Durrant 71e64e163b docs: Introduce xenstore paths for PV driver information
For domain management purposes it is convenient to be able to see
information about PV drivers in xenstore. The XAPI toolstack in
XenServer has always created a ~/drivers path for this purpose.

This patch documents that path and also adds a specification of how
it should be used.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Cc: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2015-11-24 16:19:00 +00:00
Paul Durrant 85e3b08eb7 docs: Introduce xenstore paths for PV control features
XenServer already makes use of ~/control/feature-suspend being written
to advertise guest capability of responding to 'suspend' when written to
~/control/shutdown and, since they are derived from XenServer drivers,
the Xen Project Windows PV drivers attempt to write this value. The write
currently fails for libxl provisioned VMs because ~/control is read-only
to the guest (only ~/control/shutdown is writable, for ackowledgement
purposes).

This patch documents feature-suspend and also a set of similar control
feature flags, so that that they may be added to libxl provisioned
guests by subsequent patches:

feature-poweroff: PV drivers/agent can shut down the guest
feature-reboot: PV drivers/agent can reboot the guest
feature-s3: PV drivers/agent can trigger guest sleep (HVM only)
feature-s4: PV drivers/agent can trigger guest hibernate (HVM only)

The patch (bacause it adds features relating to S3 and S4 power states)
also clarifies that the initial set of platform properties mentioned are
booleans, and updates the specifier accordingly.

Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Keir Fraser <keir@xen.org>
Cc: Tim Deegan <tim@xen.org>
2015-11-24 16:19:00 +00:00
Yang Hongyang 6e1b7ac4ed libxl/remus: setup and control network output buffering
This patch adds the machinery required for protecting a guest's
network device state. This patch comprises of two parts:

1. Hotplug scripts: The remus-netbuf-setup script is responsible for
  setting up and tearing down the necessary infrastructure required for
  network output buffering.  This script should be invoked by libxl for
  each of the guest's network interfaces, when starting or stopping Remus.

  Apart from returning success/failure indication via the usual hotplug
  entries in xenstore, this script also writes to xenstore, the name of
  the REMUS_IFB device to be used to control the vif's network output.

  The script relies on libnl3 command line utilities to perform various
  setup/teardown functions. The script is confined to Linux platforms only
  since NetBSD does not seem to have libnl3.

2. Remus network device: Implements the interfaces required by the
   remus abstract device layer. A note about the implementation:

   a) init_subkind_nic() & cleanup_subkind_nic() are called once per Remus
      invocation. They establish and free netlink related state respectively.

   b) setup() and teardown are called for each vif attached to the
      guest.
      During setup():
      i) The hotplug script is called to setup a network buffer on a
         given vif. The script chooses an available IFB device from
         the system, redirects vif egress traffic to the IFB device
         and sets up the plug qdisc (output buffer) on the IFB device.
         The name of the IFB device is communicated via xenstore to
         libxl.

      ii) Libxl obtains a handle to the plug qdisc using the libnl3 API
          and subsequently controls output buffering using this handle
          in the checkpoint callbacks.

      During teardown(), the hotplug scripts are called again to remove
      the vif->ifb traffic redirection, release the ifb and the plug
      qdisc associated with it.

   c) The checkpoint callbacks [postsuspend(), preresume() and commit()]
      are implemented as synchronous ops as the netlink calls associated
      with the qdisc subsystem are very fast.

Signed-off-by: Shriram Rajagopalan <rshriram@cs.ubc.ca>
Signed-off-by: Yang Hongyang <yanghy@cn.fujitsu.com>
Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2014-09-26 15:12:37 +01:00
David Vrabel ad1746e370 docs: update docs for the ~/platform/generation-id key
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2014-06-27 15:56:05 +01:00
Ian Jackson a8da824950 docs: Document event-channel-based suspend protocol
Document the event channel protocol in xenstore-paths.markdown, in the
section for ~/device/suspend/event-channel.

Protocol reverse-engineered from commentary and commit messages of
  4539594d46  Add facility to get notification of domain suspend ...
  17636f47a4  Teach xc_save to use event-channel-based ...
and implementations in
  xc_save (current version)
  libxl (current version)
  linux-2.6.18-xen (mercurial 1241:2993033a77ca)

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
CC: Keir Fraser <keir@xen.org>
CC: Shriram Rajagopalan <rshriram@cs.ubc.ca>
2014-01-07 13:31:20 +00:00
Roger Pau Monne d1cb516db2 libxl: create a local xenstore libxl and device-model dir for guests
If libxl is executed inside a guest domain it needs write access to
the local libxl xenstore dir (/local/<domid>/libxl) to store internal
data. This also applies to Qemu which needs a
/local/<domid>/device-model xenstore directory.

This patch creates the mentioned directories for each guest launched
from libxl.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
2013-11-18 17:08:42 +00:00
George Dunlap cb9ac9fda3 docs: Update xenstore-paths.markdown with new hvmloader key
Signed-off-by: George Dunlap <george.dunlap@eu.citrix.com>
CC: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@citrix.com>
2013-06-26 11:43:32 +01:00
Frediano Ziglio c5a29a8732 genid: Update Windows generation ID
First draft specification document it as a 64bit counter, now are a 128bit
value handled as a couple of 64bit values.

Allow to disable the device is values are all zeroes.

Add documentation for platform/generation-id key.

Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
2013-02-21 16:47:49 +00:00
Ian Campbell 5c88d313c0 docs: initial documentation for xenstore paths
This is based upon my inspection of a system with a single PV domain
and a single HVM domain running and is therefore very incomplete.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Committed-by: Ian Jackson <ian.jackson@eu.citrix.com>
2012-10-01 17:54:11 +01:00