The sending side shouldn't send any data records which end up having
zero-length content, but the receiving side will need to tolerate such
records for compatibility purposes.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
[ wei: fix typos etc ]
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
In order to distinguish guest-generated SErrors from hypervisor-generated
SErrors we have to place SError checking code in every EL1 <-> EL2 paths.
That will cause overhead on entries and exits due to dsb/isb.
However, not all platforms want to categorize SErrors. For example, a host
that is running with trusted guests. The administrator can confirm that
all guests that are running on the host will not trigger such SErrors. In
this use-case, we should provide some options to administrators to avoid
categorizing SErrors and then reduce the overhead of dsb/isb.
We provided the following 3 options to administrators to determine how
the hypervisors handle SErrors:
* `diverse`:
The hypervisor will distinguish guest SErrors from hypervisor SErrors.
The guest generated SErrors will be forwarded to guests, the hypervisor
generated SErrors will cause the whole system to crash.
It requires:
1. dsb/isb on all EL1 -> EL2 trap entries to categorize SErrors
correctly.
2. dsb/isb on EL2 -> EL1 return paths to prevent slipping hypervisor
SErrors to guests.
3. dsb/isb in context switch to isolate SErrors between 2 vCPUs.
* `forward`:
The hypervisor will not distinguish guest SErrors from hypervisor
SErrors. All SErrors will be forwarded to guests, except the SErrors
generated when the idle vCPU is running. The idle domain doesn't have
the ability to handle SErrors, so we have to crash the whole system when
we get SErros with the idle vCPU. This option will avoid most overhead
of the dsb/isb, except the dsb/isb in context switch which is used to
isolate the SErrors between 2 vCPUs.
* `panic`:
The hypervisor will not distinguish guest SErrors from hypervisor SErrors.
All SErrors will crash the whole system. This option will avoid all
overhead of the dsb/isb pairs.
Signed-off-by: Wei Chen <Wei.Chen@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Having an off by default option allowing guests to join
_any_ shared pool is not very secure.
Lets eliminate tmem_shared_auth bootup option (which
was disabled by default) and have the code force this by default.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
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>
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>
A number of changes have been made to how we determine whether TSC
is emulated (e.g. commit 4fc380ac00 ("x86/time: don't use virtual TSC
if host and guest frequencies are equal")).
Update the man page to reflect those changes
Suggested-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Add functions to libxl to setup a Xen 9pfs frontend/backend connection.
Add support to xl to parse a 9pfs option in the VM config file, in the
following format:
p9=["tag=share_dir,security_model=none,path=/root/share_dir"]
where tag identifies the 9pfs share and it is required to mount it on
the guest side, path is the path of the filesystem to share and the only
security_model supported is "none" which means that files are stored
using the same credentials as they are created on the guest (no user
ownership squash or remap).
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Classic PV shadow paging Dom0 has been broken for years, and can't
possibly be configured after 4045953.
PVH shadow paging Dom0 should still be possible.
Change the code and documentation to clarify that.
Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper@citrix.com>
Recent discussions on xen-devel have highlighted that to properly
support displacing emulated NVMe disks with PV equivalents will need
updates to PV frontends. Therefore it is important that, if an emulated
NVMe disk is exposed to a guest with an existing PV storage frontend,
that frontend does not inadvertently cause unplug of that emulated
disk when unplugging IDE or SCSI disks.
This patch defines a new bit in the mask used to instruct QEMU to unplug
emulated devices which will instruct QEMU to unplug NVMe disks and limits
the semantics of the existing 'all' disk-unplug bit to only IDE and/or SCSI
disks.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
Section 2.4.4 of the Hypervisor Top Level Functional Specification states
that enabling bit 10 in EDX of CPUID leaf 3 advertises to Windows a set
of MSRs into which it can write crash information.
This patch advertises that bit and implements the MSRs such that Xen can
log the information if a Windows guest crashes.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
The current threshold before the guest issues the hypercall is, and always
has been, hard-coded to 2047. It is not clear where this number came
from so, to at least allow for ease of experimentation, this patch makes
the threshold tunable via the Xen command line.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The Hypervisor Top Level Functional Specification v5.0a states in section
2.5:
"The hypervisor version information is encoded in leaf 0x40000002. Two
version numbers are provided: the main version and the service version.
The main version includes a major and minor version number and a build
number. These correspond to Microsoft Windows release numbers."
It also goes on to advise clients (i.e. guest versions of Windows) to use
the following algorithm to determine compatibility with the hypervisor
enlightenments:
if <your-main-version> greater than <hypervisor-main-version>
{
your version is compatible
}
else if <your-main-version> equal to <hypervisor-main-version> and
<your-service-version> greater than or equal to <hypervisor-service-version>
{
your version is compatible
}
else
{
your version is NOT compatible
}
So, clearly putting Xen hypervisor version information in that leaf is
spurious, but we probably get away with it because Xen's major version
is lower than the major version of Windows in which Hyper-V first
appeared (Server 2008).
This patch changes the leaf to use the kernel major and minor
versions, and build number from Windows Server 2008 (64-bit) by default.
These default values can be overriden from the Xen command line using new
'viridian-version' parameter.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Introduce new Xen command line parameter called "vwfi", which stands for
virtual wfi. The default is "trap": Xen traps guest wfi and wfe
instructions. In the case of wfi, Xen calls vcpu_block on the guest
vcpu; in the case of guest wfe, Xen calls vcpu_yield on the guest vcpu.
The behavior can be changed by setting vwfi to "native", in that case
Xen doesn't trap neither wfi nor wfe, running them in guest context.
The result is strong reduction in irq latency (from 5000ns to 2000ns,
measured using https://github.com/edgarigl/tbm, the physical timer, and
1 pcpu dedicated to 1 vcpu). The downside is that the scheduler thinks
that the guest is busy when actually is sleeping, leading to suboptimal
scheduling decisions.
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Dario Faggioli <dario.faggioli@citrix.com>
Reviewed-by: Julien Grall <julien.grall@arm.com>
PV Calls is a paravirtualized protocol that allows the implementation of
a set of POSIX functions in a different domain. The PV Calls frontend
sends POSIX function calls to the backend, which implements them and
returns a value to the frontend and acts on the function call.
This version of the document covers networking function calls, such as
connect, accept, bind, release, listen, poll, recvmsg and sendmsg; but
the protocol is meant to be easily extended to cover different sets of
calls. Unimplemented commands return ENOTSUP.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
9pfs is a network filesystem protocol developed for Plan 9. 9pfs is very
simple and describes a series of commands and responses. It is
completely independent from the communication channels, in fact many
clients and servers support multiple channels, usually called
"transports". For example the Linux client supports tcp and unix
sockets, fds, virtio and rdma.
This design document outlines the transport protocol for
9pfs payload.
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
As some users have suggested, elaborate the usage of RMRR specification
on the command line, and provide a usage example.
Also, always treat the specified page numbers as hexadecimal values.
Signed-off-by: Venu Busireddy <venu.busireddy@oracle.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
The default dom0_mem is 128M which is not sufficient to boot a Ubuntu
based Dom0. It is not clear what a better default value could be.
Instead, loudly warn the user when dom0_mem is unspecified and wait 3
secs. Then use 512M.
Update the docs to specify that dom0_mem is required on ARM. (The
current xen-command-line document does not actually reflect the current
behavior of dom0_mem on ARM correctly.)
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
There have been reports that Fedora 25 uses /run instead of /var/run.
Add a --with-rundir option ito configure to be able to specify that
directory. Default is still /var/run.
A re-run of autogen.sh is required.
Signed-off-by: Juergen Gross <jgross@suse.com>
[ wei: run autogen.sh ]
Acked-by: Wei Liu <wei.liu2@citrix.com>
PVHv2 guests, unlike HVM guests, won't have the option to route interrupts
from physical or emulated devices over event channels using PIRQs. This
applies to both DomU and Dom0 PVHv2 guests.
Introduce a new XEN_X86_EMU_USE_PIRQ to notify Xen whether a HVM guest can
route physical interrupts (even from emulated devices) over event channels,
and is thus allowed to use some of the PHYSDEV ops.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Split the Dom0 builder into two different functions, one for PV (and classic
PVH), and another one for PVHv2. Introduce a new command line parameter called
'dom0' that can be used to request the creation of a PVHv2 Dom0 by setting the
'hvm' sub-option. A panic has also been added if a user tries to use dom0=hvm
until all the code is in place, then the panic will be removed.
While there mark the dom0_shadow option that was used by PV Dom0 as deprecated,
it was lacking documentation and was not functional. Point users towards
dom0=shadow instead.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The information given in the xl man page for the mem-max command is
rather brief. Expand it in order to let the reader understand what it
is really doing.
As the related libxl function libxl_domain_setmaxmem() isn't much
clearer add a comment to it explaining the desired semantics.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The documentation states that a value of '1' will cause unplug of
emulated IDE disks. This is not quite correct, as QEMU will also unplug
emulated SCSI disks at the same time.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
...as a set of hypercalls to be used by a device model.
As stated in the new docs/designs/dm_op.markdown:
"The aim of DMOP is to prevent a compromised device model from
compromising domains other then the one it is associated with. (And is
therefore likely already compromised)."
See that file for further information.
This patch simply adds the boilerplate for the hypercall.
Signed-off-by: Paul Durrant <paul.durrant@citrix.com>
Suggested-by: Ian Jackson <ian.jackson@citrix.com>
Suggested-by: Jennifer Herbert <jennifer.herbert@citrix.com>
Acked-by: Daniel De Graaf <dgdegra@tycho.nsa.gov>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
On some platforms firmware fails to specify RMRR regions in ACPI tables and
thus those regions will not be mapped in dom0 or guests and may cause IO
Page Faults and prevent dom0 from booting if "iommu=dom0-strict" option is
specified on the Xen command line.
New Xen command line option rmrr allows to specify such devices and
memory regions. These regions are added to the list of RMRR defined in ACPI
if the device is present in system. As a result, additional RMRRs will be
mapped 1:1 in dom0 with correct permissions.
The above mentioned problems were discovered during the PVH work with
ThinkCentre M and Dell 5600T. No official documentation was found so far
in regards to what devices and why cause this. Experiments show that
ThinkCentre M USB devices with enabled debug port generate DMA read
transactions to the regions of memory marked reserved in host e820 map.
For Dell 5600T the device and faulting addresses are not found yet.
For detailed history of the discussion please check following threads:
http://lists.Xen.org/archives/html/xen-devel/2015-02/msg01724.htmlhttp://lists.Xen.org/archives/html/xen-devel/2015-01/msg02513.html
Format for rmrr Xen command line option:
rmrr=start<-end>=[s1]bdf1[,[s1]bdf2[,...]];start<-end>=[s2]bdf1[,[s2]bdf2[,...]]
For example, for Lenovo ThinkCentre M, use:
rmrr=0xd5d45=0:0:1d.0;0xd5d46=0:0:1a.0
If grub2 used and multiple ranges are specified, ';' should be
quoted/escaped, refer to grub2 manual for more information.
Signed-off-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Signed-off-by: Venu Busireddy <venu.busireddy@oracle.com>
Acked-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
tscmode.txt is referenced in xl.cfg(5). Convert it into a pod
formatted man page.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
pci-device-reservations is references in xl.cfg(5), convert it as a man
page in pod format. The name is now prefixed with 'xen-' to avoid
possible name conflicts.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
channel.txt is referenced in xl.cfg(5). Move it to man pages, section 7.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
vtpmmgr.txt is referenced in a man page, convert it to a man page.
The man page is named xen-vtpmmgr to avoid any conflict with other
potential vtpm docs.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
vtpm.txt is referenced in xl.cfg man page. Convert it to pod,
move it to the man folder and update the reference. The man page
is named xen-vtmp to avoid any potential conflict with other
VTPM documentation.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
docs/misc/xl-numa-placement.markdown is referenced by xl.cfg.5 man page,
move it to a man page, section 7.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Make vbd-interface a man page, section7, as this document is
referenced in other man pages (xl-disk-configuration)
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Convert xl-disk-configuration.txt from plain text file to a POD file
to get it as a man page. The references to it in the other man pages
are also updated.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Move docs/misc/xl-network-configuration.markdown to docs/man and
update the references to it in the other man pages.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Some of the docs/misc documents will need to go in man 7 section,
prepare docs/Makefile for it.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Some of the docs/misc documents are written in markdown language.
As an effort to cleanup man pages these documents will be converted into
man pages. To avoid some more conversion, add rules to the docs/Makefile
to generate man pages out of markdown files as well as pod ones.
However, pandoc doesn't know how to convert man pages links. Thus the
man links in markdown pages won't work.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
The hypervisor expects the timeout from the hypercall to be in
nanoseconds, so document this correctly. Also correctly document
what happens when timeout is set to zero.
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Qdisk supports qcow and qcow2, extend it to also support qed disk
format.
Signed-off-by: Cédric Bosdonnat <cbosdonnat@suse.com>
[ wei: regenerate libxlu_disk_l.{c,h} ]
Acked-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Andrew Cooper