Before actually enabling their use, provide a means to suppress it in
case of problems. Note that using the option can also affect the sharing
of page tables in the VT-d / EPT combination: If EPT would use large
page mappings but the option is in effect, page table sharing would be
suppressed (to properly fulfill the admin request).
Requested-by: Roger Pau Monné <roger.pau@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Paul Durrant <paul@xen.org>
With debug info retained, xen.efi can be quite large. Unlike for xen.gz
there's no intermediate step (mkelf32 there) involved which would strip
debug info kind of as a side effect. While the installing of xen.efi on
the EFI partition is an optional step (intended to be a courtesy to the
developer), adjust it also for the purpose of documenting what distros
would be expected to do during boot loader configuration (which is what
would normally put xen.efi into the EFI partition).
Model the control over stripping after Linux'es module installation,
except that the stripped executable is constructed in the build area
instead of in the destination location. This is to conserve on space
used there - EFI partitions tend to be only a few hundred Mb in size.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Henry Wang <Henry.Wang@arm.com>
Tested-by: Wei Chen <Wei.Chen@arm.com> # arm
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Add documentation for an extension of the WATCH command used to limit
the scope of watched paths. Additionally it enables to receive more
information in the events related to special watches (@introduceDomain
or @releaseDomain).
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Add documentation for two new Xenstore wire commands SET_QUOTA and
GET_QUOTA used to set or query the Xenstore quota of a given domain.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Add documentation for two new Xenstore wire commands SET_FEATURE and
GET_FEATURE used to set or query the Xenstore features visible in the
ring page of a given domain.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Branch Type Confusion affects AMD/Hygon CPUs on Zen2 and earlier. To
mitigate, we require SMT safety (STIBP on Zen2, no-SMT on Zen1), and to issue
an IBPB on each entry to Xen, to flush the BTB.
Due to performance concerns, dom0 (which is trusted in most configurations) is
excluded from protections by default.
Therefore:
* Use STIBP by default on Zen2 too, which now means we want it on by default
on all hardware supporting STIBP.
* Break the current IBPB logic out into a new function, extending it with
IBPB-at-entry logic.
* Change the existing IBPB-at-ctxt-switch boolean to be tristate, and disable
it by default when IBPB-at-entry is providing sufficient safety.
If all PV guests on the system are trusted, then it is recommended to boot
with `spec-ctrl=ibpb-entry=no-pv`, as this will provide an additional marginal
perf improvement.
This is part of XSA-407 / CVE-2022-23825.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Support controling the PV/HVM suboption of msr-sc/rsb/md-clear, which
previously wasn't possible.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Introduce a new per-domain creation x86 specific flag to
select whether hardware assisted virtualization should be used for
x{2}APIC.
A per-domain option is added to xl in order to select the usage of
x{2}APIC hardware assisted virtualization, as well as a global
configuration option.
Having all APIC interaction exit to Xen for emulation is slow and can
induce much overhead. Hardware can speed up x{2}APIC by decoding the
APIC access and providing a VM exit with a more specific exit reason
than a regular EPT fault or by altogether avoiding a VM exit.
On the other hand, being able to disable x{2}APIC hardware assisted
virtualization can be useful for testing and debugging purposes.
Note:
- vmx_install_vlapic_mapping doesn't require modifications regardless
of whether the guest has "Virtualize APIC accesses" enabled or not,
i.e., setting the APIC_ACCESS_ADDR VMCS field is fine so long as
virtualize_apic_accesses is supported by the CPU.
- Both per-domain and global assisted_x{2}apic options are not part of
the migration stream, unless explicitly set in the respective
configuration files. Default settings of assisted_x{2}apic done
internally by the toolstack, based on host capabilities at create
time, are not migrated.
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jane Malalane <jane.malalane@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: "Roger Pau Monné" <roger.pau@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: George Dunlap <george.dunlap@citrix.com>
As it is coming up basically every release cycle of Xen, add a
reference to the discussion why the current release scheme has been
selected in the release management documentation.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Henry Wang <Henry.Wang@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Allow administrators to notify a frontend driver that it's backend
counterpart is not to be trusted, so the frontend can deploy whatever
mitigations required in order to secure itself.
Allow such option for disk and network frontends only, as those are
the only hardened ones currently supported.
This is part of XSA-403
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Add instructions on how to build cppcheck, the version currently used
and an example to use the cppcheck integration to run the analysis on
the Xen codebase
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
STIBP and PSFD are slightly weird bits, because they're both implied by other
bits in MSR_SPEC_CTRL. Add fine grain controls for them, and take the
implications into account when setting IBRS/SSBD.
Rearrange the IBPB text/variables/logic to keep all the MSR_SPEC_CTRL bits
together, for consistency.
However, AMD have a hardware hint CPUID bit recommending that STIBP be set
unilaterally. This is advertised on Zen3, so follow the recommendation.
Furthermore, in such cases, set STIBP behind the guest's back for now. This
has negligible overhead for the guest, but saves a WRMSR on vmentry. This is
the only default change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Instead of specifying the feature bits in xenstore-ring.txt as a mask
value use bit numbers. This will make the specification easier to read
when adding more features.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Per Xen's support statement, PCI passthrough should be to trusted domains
because the overall system security depends on factors outside of Xen's
control.
As such, Xen, in a supported configuration, is not vulnerable to DRPW/SBDR.
However, users who have risk assessed their configuration may be happy with
the risk of DoS, but unhappy with the risk of cross-domain data leakage. Such
users should enable this option.
On CPUs vulnerable to MDS, the existing mitigations are the best we can do to
mitigate MMIO cross-domain data leakage.
On CPUs fixed to MDS but vulnerable MMIO stale data leakage, this option:
* On CPUs susceptible to FBSDP, mitigates cross-domain fill buffer leakage
using FB_CLEAR.
* On CPUs susceptible to SBDR, mitigates RNG data recovery by engaging the
srb-lock, previously used to mitigate SRBDS.
Both mitigations require microcode from IPU 2022.1, May 2022.
This is part of XSA-404.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Currently, VERW flushing to mitigate MDS is boot time conditional per domain
type. However, to provide mitigations for DRPW (CVE-2022-21166), we need to
conditionally use VERW based on the trustworthiness of the guest, and the
devices passed through.
Remove the PV/HVM alternatives and instead issue a VERW on the return-to-guest
path depending on the SCF_verw bit in cpuinfo spec_ctrl_flags.
Introduce spec_ctrl_init_domain() and d->arch.verw to calculate the VERW
disposition at domain creation time, and context switch the SCF_verw bit.
For now, VERW flushing is used and controlled exactly as before, but later
patches will add per-domain cases too.
No change in behaviour.
This is part of XSA-404.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Introduce a command line parameter "maxcpus" on Arm to allow adjusting
the number of CPUs to activate. Currently the limit is defined by the
config option CONFIG_NR_CPUS. Such parameter already exists on x86.
Define a parameter "maxcpus" and a corresponding static variable
max_cpus in Arm smpboot.c. Modify function smp_get_max_cpus to take
max_cpus as a limit and to return proper unsigned int instead of int.
Take the opportunity to remove redundant variable cpus from start_xen
function and to directly assign the return value from smp_get_max_cpus
to nr_cpu_ids (global variable in Xen used to store the number of CPUs
actually activated).
Signed-off-by: Michal Orzel <michal.orzel@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Add Rule 5.1, with the additional note that the character limit for Xen
is 40 characters.
The max length identifiers found by ECLAIR are:
__mitigate_spectre_bhb_clear_insn_start
domain_pause_by_systemcontroller_nosync
Both of them are 40 characters long.
Explicitly mention that public headers might have longer identifiers.
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Introduce a list of MISRA C rules that apply to the Xen hypervisor. The
list is in RST format.
Specify that rules deviations need to be documented. Introduce a
documentation tag for in-code comments to mark them as deviations. Also
mention that other documentation mechanisms are work-in-progress.
Add a mention of the new list to CODING_STYLE.
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Signed-off-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
When xs_introduce_domain is called, send out a notification on the
xenstore event channel so that any (dom0less) domain waiting for the
xenstore interface to be ready can continue with the initialization.
Before sending the notification, clear XENSTORE_RECONNECTING.
The extra notification is harmless for domains that don't require it.
In xs_wire.h update the commment on top of XENSTORE_RECONNECTING to
generalize its meaning to suit the dom0less use-case better. Also
improve docs/misc/xenstore-ring.txt.
Signed-off-by: Luca Miccio <lucmiccio@gmail.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Introduce a new "xen,enhanced" dom0less property to enable/disable PV
driver interfaces for dom0less guests. Currently only "enabled" and
"disabled" are supported property values (and empty). Leave the option
open to implement further possible values in the future (e.g.
"xenstore" to enable only xenstore.) Dom0 presence is required for now
to use "xen,enhanced" on a domU.
The configurable option is for domUs only. For dom0 we always set the
corresponding property in the Xen code to true (PV interfaces enabled.)
This patch only parses the property. Next patches will make use of it.
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Acked-by: Julien Grall <jgrall@amazon.com>
CC: Julien Grall <julien@xen.org>
CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
CC: Bertrand Marquis <bertrand.marquis@arm.com>
Implement extended regions for dom0less domUs. The implementation is
based on the libxl implementation.
Also update docs for the ext_regions command line option.
Signed-off-by: Stefano Stabellini <stefano.stabellini@xilinx.com>
Reviewed-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com>
Acked-by: Julien Grall <jgrall@amazon.com>
libxl_domain_setmaxmem() called during "xl mem-max" should update the
domain's memory/static-max Xenstore node, as otherwise "xl mem-set"
won't be able to set the memory size to the new maximum.
Adjust the related comments and documentation accordingly.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
Introduce domain-cpupool property of a xen,domain device tree node,
that specifies the cpupool device tree handle of a xen,cpupool node
that identifies a cpupool created at boot time where the guest will
be assigned on creation.
Add member to the xen_domctl_createdomain public interface so the
XEN_DOMCTL_INTERFACE_VERSION version is bumped.
Add public function to retrieve a pool id from the device tree
cpupool node.
Update documentation about the property.
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Introduce a way to create different cpupools at boot time, this is
particularly useful on ARM big.LITTLE system where there might be the
need to have different cpupools for each type of core, but also
systems using NUMA can have different cpu pools for each node.
The feature on arm relies on a specification of the cpupools from the
device tree to build pools and assign cpus to them.
ACPI is not supported for this feature.
With this patch, cpupool0 can now have less cpus than the number of
online ones, so update the default case for opt_dom0_max_vcpus.
Documentation is created to explain the feature.
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Acked-by: George Dunlap <george.dunlap@citrix.com>
AMD have updated their Spectre v2 guidance, and lfence/jmp is no longer
considered safe. AMD are recommending using retpoline everywhere.
Retpoline is incompatible with CET. All CET-capable hardware has efficient
IBRS (specifically, not something retrofitted in microcode), so use IBRS (and
STIBP for consistency sake).
This is a logical change on AMD, but not on Intel as the default calculations
would end up with these settings anyway. Leave behind a message if IBRS is
found to be missing.
Also update the default heuristics to never select THUNK_LFENCE. This causes
AMD CPUs to change their default to retpoline.
Also update the printed message to include the AMD MSR_SPEC_CTRL settings, and
STIBP now that we set it for consistency sake.
This is part of XSA-398 / CVE-2021-26401.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Defaults differ for Arm and x86, not the least because of v2 not even
being security supported on Arm.
Also drop a bogus sentence from gnttab_max_maptrack_frames, which was
presumably mistakenly cloned from gnttab_max_frames (albeit even there
what is being said is neither very precise nor very useful imo).
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Add a document to describe the rules for sending a proper patch.
As it contains all the information already being present in
docs/process/tags.pandoc remove that file.
The "Reviewed-by:" and "Acked-by:" tags are expanded to allow an
optional restriction of the tag.
A new tag "Origin:" is added to tag patches taken from another project.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
The Xenstore migration document is missing the specification that a
node record must be preceded by the record of its parent node in case
of live update.
Add that missing part.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
With all the pieces now in place, turn CET-IBT on when available.
MSR_S_CET, like SMEP/SMAP, controls Ring1 meaning that ENDBR_EN can't be
enabled for Xen independently of PV32 kernels. As we already disable PV32 for
CET-SS, extend this to all CET, adjusting the documentation/comments as
appropriate.
Introduce a cet=no-ibt command line option to allow the admin to disable IBT
even when everything else is configured correctly.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Document the remaining option. Add section annotation to the variable
holding the parsed value as well as a few adjacent ones. Adjust the
types of font_height and vga_compat.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
If we get mode dimensions wrong, having the remapping size controllable
via command line option isn't going to help much. Drop the option.
While adjusting this also
- add __initdata to the variable,
- use ROUNDUP() instead of open-coding it.
Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Now that we use ioremap_wc() for mapping the frame buffer, there's no
need for this option anymore. As noted in the change introducing the
use of ioremap_wc(), mtrr_add() didn't work in certain cases anyway.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
In case Xenstore is detecting a malicious ring page modification (e.g.
an invalid producer or consumer index set by a guest) it will ignore
the connection of that guest in future.
Add a new error field to the ring page indicating that case. Add a new
feature bit in order to signal the presence of that error field.
Move the ignore_connection() function to xenstored_domain.c in order
to be able to access the ring page for setting the error indicator.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
This commit introduces a new arm-specific flag CDF_directmap to specify
that a domain should have its memory direct-map(guest physical address
== host physical address) at domain creation.
Also, add a directmap flag under struct arch_domain and use it to
reimplement is_domain_direct_mapped.
For now, direct-map is only available when statically allocated memory is
used for the domain, that is, "xen,static-mem" must be also defined in the
domain configuration.
Signed-off-by: Stefano Stabellini <sstabellini@kernel.org>
Signed-off-by: Penny Zheng <penny.zheng@arm.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Tested-by: Stefano Stabellini <sstabellini@kernel.org>
The grant table operation GNTTABOP_transfer is meant to be used in
PV device backends, and it hasn't been used in Linux since the old
Xen-o-Linux days.
Add a command line sub-option to the "gnttab" option for disabling the
GNTTABOP_transfer functionality.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
The February 2022 microcode is formally de-featuring TSX on the TAA-impacted
client CPUs. The backup TAA mitigation (VERW regaining its flushing side
effect) is being dropped, meaning that `smt=0 spec-ctrl=md-clear` no longer
protects against TAA on these parts.
The new functionality enumerates itself via the RTM_ALWAYS_ABORT CPUID
bit (the same as June 2021), but has its control in MSR_MCU_OPT_CTRL as
opposed to MSR_TSX_FORCE_ABORT.
TSX now defaults to being disabled on ucode load. Furthermore, if SGX is
enabled in the BIOS, TSX is locked and cannot be re-enabled. In this case,
override opt_tsx to 0, so the RTM/HLE CPUID bits get hidden by default.
While updating the command line documentation, take the opportunity to add a
paragraph explaining what TSX being disabled actually means, and how migration
compatibility works.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Currently the Xen UEFI stub can accept Xen boot arguments from
the Xen configuration file using the "options=" keyword, but also
directly from the device tree specifying xen,xen-bootargs
property.
When the configuration file is used, device tree boot arguments
are ignored and overwritten even if the keyword "options=" is
not used.
This patch handle this case, so if the Xen configuration file is not
specifying boot arguments, the device tree boot arguments will be
used, if they are present.
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Specifically, this lets the user opt in to non-default features.
Collect all dom0 settings together in dom0_{en,dis}able_feat[], and apply it
to dom0's policy when other tweaks are being made.
As recalculate_cpuid_policy() is an expensive action, and dom0-cpuid= is
likely to only be used by the x86 maintainers for development purposes, forgo
the recalculation in the general case.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
This avoid the need to generate the _paths.h header when the
information is from autoconf anyway.
They are no more users of the "buildmakevars2header" macro, so it can
be removed from "Config.mk".
Also removed the extra "-f" flag where "$(RM)" is used (xl/Makefile).
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
The example in section "UEFI boot and dom0less on ARM" has a wrong
compatible for the DTB passthrough, it is "ramdisk" instead of
"device-tree".
This patch fixes the example.
Fixes: a1743fc3a9 ("arm/efi: Use dom0less configuration when using EFI boot")
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Introduce a new domain create field so that toolstack can specify the
maximum grant table version usable by the domain. This is plumbed into
xl and settable by the user as max_grant_version.
Previously this was only settable on a per host basis using the
gnttab command line option.
Note the version is specified using 4 bits, which leaves room to
specify up to grant table version 15. Given that we only have 2 grant
table versions right now, and a new version is unlikely in the near
future using 4 bits seems more than enough.
xenstored stubdomains are limited to grant table v1 because the
current MiniOS code used to build them only has support for grants v1.
There are existing limits set for xenstored stubdomains at creation
time that already match the defaults in MiniOS.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
Since the introduction of UEFI boot for Xen, the legacy
compatible strings were not supported and the stub code
was checking only the presence of “multiboot,module” to
require the Xen UEFI configuration file or not.
The documentation was not updated to specify that behavior.
Add a phrase to docs/misc/arm/device-tree/booting.txt
to clarify it.
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Add support to load Dom0 boot modules from
the device tree using the xen,uefi-binary property.
Update documentation about that.
Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Acked-by: Jan Beulich <jbeulich@suse.com>
Add parameter vpmu to xl domain configuration syntax
to enable the access to PMU registers by disabling
the PMU traps(currently only for ARM).
The current status is that the PMU registers are not
virtualized and the physical registers are directly
accessible when this parameter is enabled. There is no
interrupt support and Xen will not save/restore the
register values on context switches.
According to Arm Arm, section D7.1:
"The Performance Monitors Extension is common
to AArch64 operation and AArch32 operation."
That means we have an ensurance that if PMU is
present in one exception state, it must also be
present in the other.
Please note that this feature is experimental.
Signed-off-by: Michal Orzel <michal.orzel@arm.com>
Signed-off-by: Julien Grall <julien@xen.org>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>