When started due to a live upgrade read the internal state and apply
it to the data base and internal structures.
Add the main control functions for that.
For now only handle the daemon case.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
In the live update case several initialization steps of xenstore must
be omitted or modified. Add the proper handling for that.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
For live update the functionality to introduce a new domain similar to
the XS_INTRODUCE command is needed, so split that functionality off
into a dedicated function introduce_domain().
Switch initial dom0 initialization to use this function, too.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
For support of live update the locally used files need to have the
"close on exec" flag set. Fortunately the used Xen libraries are
already doing this, so only the logging and tdb related files and
pipes are affected. openlog() has the close on exec attribute, too.
In order to be able to keep the event channels open specify the
XENEVTCHN_NO_CLOEXEC flag when calling xenevtchn_open().
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <julien.grall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Dump the complete Xenstore status to a file (daemon case) or memory
(stubdom case).
As we don't know the exact length of the needed area in advance we are
using an anonymous rather large mapping in stubdom case, which will
use only virtual address space until accessed. And as we are writing
the area in a sequential manner this is fine. As the initial size we
are choosing the double size of the memory allocated via talloc(),
which should be more than enough.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Add an include file containing all structures and defines needed for
dumping and restoring the internal Xenstore state.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
In order to simplify live update state dumping only allow live update
to happen when no transaction is active.
A timeout is used to detect guests which have a transaction active for
longer periods of time. In case such a guest is detected when trying
to do a live update it will be reported and the update will fail.
The admin can then either use a longer timeout, or use the force flag
to just ignore the transactions of such a guest, or kill the guest
before retrying.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Add the main framework for executing the live update. This for now
only defines the basic execution steps with empty dummy functions.
This final step returning means failure, as in case of success the
new executable will have taken over.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Today a Xenstore request is processed as soon as it is seen by
xenstored. Add the framework for being able to delay processing of a
request if the right conditions aren't met.
Any delayed requests are executed at the end of the main processing
loop in xenstored. They can either delay themselves again or just do
their job. In order to enable the possibility of a timeout, the main
loop will be paused for max one second if any requests are delayed.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Updating an instance of Xenstore via live update needs to hand over
the command line parameters to the updated instance. Those can be
either the parameters used by the updated instance or new ones when
supplied when starting the live update.
So when supplied store the new command line parameters in lu_status.
As it is related add a new option -U (or --live-update") to the command
line of xenstored which will be added when starting the new instance.
This enables to perform slightly different initializations when
started as a result of live update.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Wei Liu <wl@xen.org>
Save the new binary name for the daemon case and the new kernel for
stubdom in order to support live update of Xenstore..
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Live update of Xenstore is done in multiple steps. It needs a status
block holding the current state of live update and related data. It
is allocated as child of the connection live update was started over
in order to abort live update in case the connection is closed.
Allocation of the block is done in lu_binary[_alloc](), freeing in
lu_abort() (and for now in lu_start() as long as no real live-update
is happening).
Add tests in all live-update command handlers other than lu_abort()
and lu_binary[_alloc]() for being started via the same connection
as the begin of live-update.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Add the basic parts for parsing the live-update control command.
For now only add the parameter evaluation and calling appropriate
functions. Those function only print a message for now and return
success.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Add the "live-update" command to xenstore-control enabling updating
xenstored to a new version in a running Xen system.
With -c <arg> it is possible to pass a different command line to the
new instance of xenstored. This will replace the command line used
for the invocation of the just running xenstored instance.
The running xenstored (or xenstore-stubdom) needs to support live
updating, of course.
For now just add a small dummy handler to C xenstore denying any
live update action.
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
In order to allow control commands with binary data refactor handling
of XS_CONTROL:
- get primary command first
- add maximum number of additional parameters to pass to command
handler
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Acked-by: Wei Liu <wl@xen.org>
This patch modifies libxlu_pci_parse_spec_string() to parse the new 'name'
parameter of PCI_SPEC_STRING detailed in the updated documention in
xl-pci-configuration(5) and populate the 'name' field of 'libxl_device_pci'.
If the 'name' field is non-NULL then both libxl_device_pci_add() and
libxl_device_pci_remove() will use it to look up the device BDF in
the list of assignable devices.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
Since assignable devices can be named, a subsequent patch will support use
of a PCI_SPEC_STRING containing a 'name' parameter instead of a 'bdf'. In
this case the name will be used to look up the 'bdf' in the list of assignable
(or assigned) devices.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
With this patch applied 'xl pci-assignable-add' will take an optional '--name'
parameter, 'xl pci-assignable-remove' can be passed either a BDF or a name and
'xl pci-assignable-list' will take a optional '--show-names' flag which
determines whether names are displayed in its output.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
... and modify libxl_pci_bdf_assignable_add/remove/list() to make use of it.
libxl_pci_bdf_assignable_add() will store the name of the device in xenstore
if the field is specified (i.e. non-NULL) and libxl_pci_bdf_assignable_remove()
will remove devices specified only by name, looking up the BDF as necessary.
libxl_pci_bdf_assignable_list() will also populate the 'name' field if a name
was stored by libxl_pci_bdf_assignable_add().
NOTE: This patch also fixes whitespace in the declaration of 'libxl_device_pci'
in the IDL.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
There are only two call-sites. One always sets it to 0 (which is unnecessary
as the structure is already initialized to zero) and the other can simply set
the 'vdevfn' field directly (after proper structure initialization), avoiding
the need for a local variable.
A subsequent patch will also make use of pci_struct_fill() in a context
where 'vdevfn' may already have been set.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
This patch largely re-writes the code to parse a PCI_SPEC_STRING and enters
it via the newly introduced function. The new parser also deals with 'bdf'
and 'vslot' as non-positional paramaters, as per the documentation in
xl-pci-configuration(5).
The existing xlu_pci_parse_bdf() function remains, but now strictly parses
BDF values. Some existing callers of xlu_pci_parse_bdf() are
modified to call xlu_pci_parse_spec_string() as per the documentation in xl(1).
NOTE: Usage text in xl_cmdtable.c and error messages are also modified
appropriately.
As a side-effect this patch also fixes a bug where using '*' to specify
all functions would lead to an assertion failure at the end of
xlu_pci_parse_bdf().
Fixes: d25cc3ec93 ("libxl: workaround gcc 10.2 maybe-uninitialized warning")
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
A subsequent patch will introduce code to allow a name to be specified to
'xl pci-assignable-add' such that the assignable device may be referred to
by than name in subsequent operations.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Acked-by: Wei Liu <wl@xen.org>
A fix for a previous issue removed the pirqs from the domain tree when
they are unbound in order to prevent shared pirqs from triggering a
BUG_ON in __pirq_guest_unbind if they are unbound multiple times. That
caused free_domain_pirqs to no longer unmap the pirqs because they
are gone from the domain pirq tree, thus leaving stale unbound pirqs
after domain destruction if the domain had mapped dpci pirqs after
shutdown.
Take a different approach to fix the original issue, instead of
removing the pirq from d->pirq_tree clear the flags of the dpci pirq
struct to signal that the pirq is now unbound. This prevents calling
pirq_guest_unbind multiple times for the same pirq without having to
remove it from the domain pirq tree.
This is XSA-360.
Fixes: 5b58dad089 ('x86/pass-through: avoid double IRQ unbind during domain cleanup')
Reported-by: Samuel Verschelde <samuel.verschelde@vates.fr>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Currently, Xen is considering that all the affinity bits are defined
below 32-bit. However, Arm64 define a 3rd level affinity in bits 32-39.
The function gicv3_send_sgi_list in the GICv3 driver will compute the
cluster using the following code:
uint64_t cluster_id = cpu_logical_map(cpu) & ~MPIDR_AFF0_MASK;
Because MPIDR_AFF0_MASK is defined as a 32-bit value, we will miss out
the 3rd level affinity. As a consequence, the IPI would not be sent to
the correct vCPU.
This particular error can be solved by switching MPIDR_AFF0_MASK to use
unsigned long. However, take the opportunity to switch all the MPIDR_*
define to use unsigned long to avoid anymore issue.
Signed-off-by: Wei Chen <wei.chen@arm.com>
[julien: Reword the commit message]
Reviewed-by: Julien Grall <jgrall@amazon.com>
init_one_desc_irq() can return an error if it is unable to allocate
memory. While this is unlikely to happen during boot (called from
init_{,local_}irq_data()), it is better to harden the code by
propagting the return value.
Spotted by coverity.
CID: 106529
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Roger Paul Monné <roger.pau@citrix.com>
Reviewed-by: Volodymyr Babchuk <volodymyr_babchuk@epam.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
Supported values are
0b0000 GIC CPU interface system registers not implemented.
0b0001 System register interface to versions 3.0 and 4.0 of the GIC
CPU interface is supported.
0b0011 System register interface to version 4.1 of the GIC CPU
interface is supported.
4.1 is still backward compatible with 4.0/3.0, moreover ARM ARM
guarantees that future versions of the GIC CPU interface retain
backwards compatible.
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Release-Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
The ARMv8.3 Pointer Authentication extension is not supported by Xen
at the moment, so do not expose that via ID register.
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Reviewed-by: Bertrand Marquis <bertrand.marquis@arm.com>
[julien: s/__res0/__res2/ to avoid name duplication]
Reviewed-by: Julien Grall <jgrall@amazon.com>
Per the discussion [1] on the mailing list, we'd better to
have a barrier after reading CNTPCT in get_cycles. If there
is not any barrier there. When get_cycles being used in some
seqlock critical context in the future, the seqlock can be
speculated potentially.
We import Linux commit 75a19a0202db21638a1c2b424afb867e1f9a2376:
arm64: arch_timer: Ensure counter register reads occur with seqlock held
When executing clock_gettime(), either in the vDSO or via a system call,
we need to ensure that the read of the counter register occurs within
the seqlock reader critical section. This ensures that updates to the
clocksource parameters (e.g. the multiplier) are consistent with the
counter value and therefore avoids the situation where time appears to
go backwards across multiple reads.
Extend the vDSO logic so that the seqlock critical section covers the
read of the counter register as well as accesses to the data page. Since
reads of the counter system registers are not ordered by memory barrier
instructions, introduce dependency ordering from the counter read to a
subsequent memory access so that the seqlock memory barriers apply to
the counter access in both the vDSO and the system call paths.
Cc: <stable@vger.kernel.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lore.kernel.org/linux-arm-kernel/alpine.DEB.2.21.1902081950260.1662@nanos.tec.linutronix.de/
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Will Deacon <will.deacon@arm.com>
While we are not aware of such use in Xen, it would be best to add the
barrier to avoid any suprise.
In order to reduce the impact of new barrier, we perfer to
use enforce order instead of ISB [2].
Currently, enforce order is not applied to arm32 as this is
not done in Linux at the date of this patch. If this is done
in Linux it will need to be also done in Xen.
To avoid adding read_cntpct_enforce_ordering everywhere, we introduced
a new helper read_cntpct_stable to replace original get_cycles, and turn
get_cycles to a wrapper which we can add read_cntpct_enforce_ordering
easily.
[1] https://lists.xenproject.org/archives/html/xen-devel/2020-12/msg00181.html
[2] https://lkml.org/lkml/2020/3/13/645
Signed-off-by: Wei Chen <wei.chen@arm.com>
Reviewed-by: Julien Grall <jgrall@amazon.com>
... so debug builds can see what went wrong, rather than getting an
unqualified -EINVAL out of domain creation.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Similarly to c/s 98d4d6d8a6 "xen/domain: Introduce domain_teardown()",
introduce a common mechanism for restartable per-vcpu teardown logic.
Extend the PROGRESS() mechanism to support saving and restoring the vcpu loop
variable across hypercalls.
This will eventually supersede domain_reliquish_resources(), and reduce the
quantity of redundant logic performed.
No functional change (yet).
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
This is a revert of f5cfa09856 plus a rework of the comment that
accompanies the setting of the flag so we don't forget why it needs to
be unconditionally set: it's indicating whether the version of Xen has
the original issue fixed and IOMMU entries are created for
grant/foreign maps.
If the flag is only exposed when the IOMMU is enabled the guest could
resort to use bounce buffers when running backends as it would assume
the underlying Xen version still has the bug present and thus
grant/foreign maps cannot be used with devices.
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Its guard was updated such that it is visible by default when POSIX 2008
was adopted by glibc. It's not visible by default on older glibc.
Fixes: f80fe2b34f ("xen: Update Kconfig to Linux v5.4")
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Doug Goldstein <cardoe@cardoe.com>
On NetBSD the privcmd interface node is /kern/xen/privcmd
Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
remove PROCNETDEV_HEADER[] and read_attributes_vbd(), gcc complains that they
are unused
Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
NetBSD doens't need xenbackendd with xl toolstack so don't build it.
Remove now unused xenbackendd directory/files, and remaining references
in the hotplug scripts.
Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
[Also clean up stale comments in the Linux xencommons script]
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Use xenio3.h for ioctl definitions
read_exact/write_exact seems to not be available here, which cause a gcc
error. Use plain read/write, the xenevtchn interface won't do partial
read/write on NetBSD anyway so it should be safe. This is in line with the
rest of the OS specific helpers.
Fixes: b7f76a699d ('tools: Refactor /dev/xen/evtchn wrappers into libxenevtchn')
Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
On NetBSD xen/sys/evtchn.h is not available any more. Just remove it as it's
not needed.
Signed-off-by: Manuel Bouyer <bouyer@netbsd.org>
Acked-by: Christian Lindig <christian.lindig@citrix.com>
UBSAN catches an uninitialized use of the 'preempted' variable in
fork_hap_allocation when there is no preemption.
Fixes: 41548c5472 ("mem_sharing: VM forking")
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
This is cleanup for two pending series which will copy more data than just
flags from config.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Reading a gzipped string value from hypfs doesn't add a 0 byte at the
end. Fix that.
Fixes: 86234eafb9 ("libs: add libxenhypfs")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Forever since the fix for XSA-230 the 2nd of the comments ahead of
fixup_status_for_copy_pin() has been stale - there's nothing specific to
transitive grants there anymore.
Move the function up, drop the "copy" part from its name again, add a
"readonly" parameter, and use it also on other paths having decremented
one (or not having got to increment any) of the pin counts.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
It's at least odd to check counters which aren't going to be
incremented, resulting in failure just because prior operations may have
reached the refcount limit. And it's also not helpful to use open-coded
literal numbers in these checks.
Calculate the increment values first and derive from them the mask to
use in the checks.
Also move the pin count checks ahead of the calculation of the status
(and for copy also sha2) pointers: They're not needed in the failure
cases, and this way the compiler may also have an easier time keeping
the variables at least transiently in registers for the subsequent uses.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Taken from Linux at commit 1c4dd334df3a ("lib: decompress_unzstd: Limit
output size") for unzstd.c (renamed from decompress_unzstd.c) and
36f9ff9e03de ("lib: Fix fall-through warnings for Clang") for zstd/,
with bits from linux/zstd.h merged into suitable other headers.
To limit the editing necessary, introduce ptrdiff_t.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Taken from Linux at commit d89775fc929c ("lib/: replace HTTP links with
HTTPS ones"), but split into separate 32-bit and 64-bit sources, since
the immediate consumer (zstd) will need only the latter.
Note that the building of this code is restricted to x86 for now because
of the need to sort asm/unaligned.h for Arm.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Rather than open-coding commonly used constructs in yet more places when
pulling in zstd decompression support (and its xxhash prereq), pull out
the custom bits into a commonly used header (for the hypervisor build;
the tool stack and stubdom builds of libxenguest will still remain in
need of similarly taking care of). For now this is limited to x86, where
custom logic isn't needed (considering this is going to be used in init
code only, even using alternatives patching to use MOVBE doesn't seem
worthwhile).
For Arm64 with CONFIG_ACPI=y (due to efi-dom0.c's re-use of xz/crc32.c)
drop the not really necessary inclusion of xz's private.h.
No change in generated code.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Livepatch fails to build on Arm after commit ced9795c6c "mm: split
out mfn_t / gfn_t / pfn_t definitions and helpers":
In file included from livepatch.c:13:0:
/oss/xen/xen/include/asm/mm.h:32:28: error: field ‘list’ has incomplete type
struct page_list_entry list;
^~~~
/oss/xen/xen/include/asm/mm.h:53:43: error: ‘MAX_ORDER’ undeclared here (not in a function); did you mean ‘PFN_ORDER’?
unsigned long first_dirty:MAX_ORDER + 1;
^~~~~~~~~
PFN_ORDER
/oss/xen/xen/include/asm/mm.h:53:31: error: bit-field ‘first_dirty’ width not an integer constant
unsigned long first_dirty:MAX_ORDER + 1;
^~~~~~~~~~~
This is happening because asm/mm.h is included directly by livepatch.c.
Yet it depends on xen/mm.h to be included first so MAX_ORDER is defined.
Resolve the build failure by including xen/mm.h rather than asm/mm.h.
Fixes: ced9795c6c ("mm: split out mfn_t / gfn_t / pfn_t definitions and helpers")
Signed-off-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
I can only assume that f2ae59bc4b ("Rationalize max_grant_frames and
max_maptrack_frames handling") unintentionally left Arm's create_domUs()
set limits to explicit values, as at least some of the same constraints
apply here.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Stefano Stabellini <sstabellini@kernel.org>
xen/mm.h has heavy dependencies, while in a number of cases only these
type definitions are needed. This separation then also allows pulling in
these definitions when including xen/mm.h would cause cyclic
dependencies.
Replace xen/mm.h inclusion where possible in include/xen/. (In
xen/iommu.h also take the opportunity and correct the few remaining
sorting issues.)
While the change could be dropped, remove an unnecessary asm/io.h
inclusion from xen/arch/x86/acpi/power.c. This was the initial attempt
to address build issues with it, until it became clear that the header
itself needs adjustment.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>