GDS_CTRL is introduced by the August 2023 microcode. GDS_NO is for current
and future processors not susceptible to GDS.
This is part of XSA-435 / CVE-2022-40982
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 9f585f59d9)
AMD have specified new CPUID bits relating to SRSO.
* SRSO_NO indicates that hardware is no longer vulnerable to SRSO.
* IBPB_BRTYPE indicates that IBPB flushes branch type information too.
* SBPB indicates support for a relaxed form of IBPB that does not flush
branch type information.
Current CPUs (Zen4 and older) are not expected to enumerate these bits.
Native software is expected to synthesise them for guests using model and
microcode revision checks.
Two are just status bits, and SBPB is trivial to support for guests by
tweaking the reserved bit calculation in guest_wrmsr() and feature
dependencies. Expose all by default to guests, so they start showing up when
Xen synthesises them.
While adding feature dependenies for IBPB, fix up an overlooked issue from
XSA-422. It's inappropriate to advertise that IBPB flushes RET predictions if
IBPB is unavailable itself.
This is part of XSA-434 / CVE-2023-20569
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>
(cherry picked from commit 2280b0ee2a)
Seed the default visibility from the dom0 special case, which for the most
part just exposes the *_NO bits. EIBRS is the one non-*_NO bit, which is
"just" a status bit to the guest indicating a change in implemention of IBRS
which is already fully supported.
Insert a block dependency from the ARCH_CAPS CPUID bit to the entire content
of the MSR. This is because MSRs have no structure information similar to
CPUID, and used by x86_cpu_policy_clear_out_of_range_leaves(), in order to
bulk-clear inaccessable words.
The overall CPUID bit is still max-only, so all of MSR_ARCH_CAPS is hidden in
the default policies.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit ce8c930851)
Bits through 24 are already defined, meaning that we're not far off needing
the second word. Put both in right away.
As both halves are present now, the arch_caps field is full width. Adjust the
unit test, which notices.
The bool bitfield names in the arch_caps union are unused, and somewhat out of
date. They'll shortly be automatically generated.
Add CPUID and MSR prefixes to the ./xen-cpuid verbose output, now that there
are a mix of the two.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit d9fe459ffa)
Featuresets are supposed to be disappearing when the CPU policy infrastructure
is complete, but that has taken longer than expected, and isn't going to be
complete imminently either.
In the meantime, Xen does have proper default/max featuresets, and xen-cpuid
can even get them via the XEN_SYSCTL_cpu_policy_* interface, but only knows
now to render them nicely via the featureset interface.
Differences between default and max are a frequent source of errors,
frequently too in secret leading up to an embargo, so extend the featureset
sysctl to allow xen-cpuid to render them all nicely.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Christian Lindig <christian.lindig@cloud.com>
(cherry picked from commit 433d012c6c)
struct fsinfo is the vestigial remnant of an older internal design which
didn't survive very long.
Simplify things by inlining get_featureset() and having a single memory
allocation that gets reused. This in turn changes featuresets[] to be a
simple list of names, so rename it to fs_names[].
No functional change.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit ec3474e1dd)
We don't actually need ecx yet, but adding it in now will reduce the amount to
which leaf 7 is out of order in a featureset.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit b4a23bf629)
The IBPB_RET bit indicates that the CPU's implementation of MSR_PRED_CMD.IBPB
does flush the RSB/RAS too.
This is part of XSA-422 / CVE-2022-23824.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 24496558e6)
BTC_NO indicates that hardware is not succeptable to Branch Type Confusion.
Zen3 CPUs don't suffer BTC.
This is part of XSA-407.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 76cb04ad64)
The Feb 2022 microcode from Intel retrofits AMD's MSR_SPEC_CTRL.PSFD interface
to Sunny Cove (IceLake) and later cores.
Update the MSR_SPEC_CTRL emulation, and expose it to guests.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 52ce1c9784)
While in principle it would be nice to keep leaf 7 in order, that would
involve having an extra 5 words of zeros in a featureset.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit f3709b15fc)
AMD Milan (Zen3) CPUs have an LFENCE Always Serialising CPUID bit in
leaf 80000021.eax. Previous AMD versions used to have a user settable
bit in DE_CFG MSR to select whether LFENCE was dispatch serialising,
which Xen always attempts to set. The forcefully always on setting is
due to the addition of SEV-SNP so that a VMM cannot break the
confidentiality of a guest.
In order to support this new CPUID bit move the LFENCE_DISPATCH
synthetic CPUID bit to map the hardware bit (leaving a hole in the
synthetic range) and either rely on the bit already being set by the
native CPUID output, or attempt to fake it in Xen by modifying the
DE_CFG MSR. This requires adding one more entry to the featureset to
support leaf 80000021.eax.
The bit is always exposed to guests by default even if the underlying
hardware doesn't support leaf 80000021. Note that Xen doesn't allow
guests to change the DE_CFG value, so once set by Xen LFENCE will always
be serialising.
Note that the access to DE_CFG by guests is left as-is: reads will
unconditionally return LFENCE_SERIALISE bit set, while writes are
silently dropped.
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
[Always expose to guests by default]
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit e9b4fe2636)
x86/cpuid: do not expand max leaves on restore
When restoring limit the maximum leaves to the ones supported by Xen
4.12 in order to not expand the maximum leaves a guests sees. Note
this is unlikely to cause real issues.
Guests restored from Xen versions 4.13 or greater will contain CPUID
data on the stream that will override the values set by
xc_cpuid_apply_policy.
Fixes: e9b4fe2636 ("x86/cpuid: support LFENCE always serialising CPUID bit")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 111c8c33a8)
tools/libxenguest: Fix max_extd_leaf calculation for legacy restore
0x1c is lower than any value which will actually be observed in
p->extd.max_leaf, but higher than the logical 9 leaves worth of extended data
on Intel systems, causing x86_cpuid_copy_to_buffer() to fail with -ENOBUFS.
Correct the calculation.
The problem was first noticed in c/s 34990446ca "libxl: don't ignore the
return value from xc_cpuid_apply_policy" but introduced earlier.
Fixes: 111c8c33a8 ("x86/cpuid: do not expand max leaves on restore")
Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 5fa174cbf5)
tools/guest: Fix comment regarding CPUID compatibility
It was Xen 4.14 where CPUID data was added to the migration stream, and 4.13
that we need to worry about with regards to compatibility. Xen 4.12 isn't
relevant.
Expand and correct the commentary.
Fixes: 111c8c33a8 ("x86/cpuid: do not expand max leaves on restore")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 820cc39343)
TSXLDTRK lives in CPUID leaf 7[0].edx, not 7[0].ecx.
Bit 16 in ecx is LA57.
Fixes: a6d1b55847 ("x86emul: support X{SUS,RES}LDTRK")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 249e0f1d8f
master date: 2021-12-14 12:30:48 +0000
There is a step change in speculation protections between the Zen1 and Zen2
microarchitectures.
Zen1 and older have no special support. Control bits in non-architectural
MSRs are used to make lfence be dispatch-serialising (Spectre v1), and to
disable Memory Disambiguation (Speculative Store Bypass). IBPB was
retrofitted in a microcode update, and software methods are required for
Spectre v2 protections.
Because the bit controlling Memory Disambiguation is model specific,
hypervisors are expected to expose a MSR_VIRT_SPEC_CTRL interface which
abstracts the model specific details.
Zen2 and later implement the MSR_SPEC_CTRL interface in hardware, and
virtualise the interface for HVM guests to use. A number of hint bits are
specified too to help guide OS software to the most efficient mitigation
strategy.
Zen3 introduced a new feature, Predictive Store Forwarding, along with a
control to disable it in sensitive code.
Add CPUID and VMCB details for all the new functionality.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 747424c664
master date: 2021-09-08 14:16:19 +0100
The June 2021 microcode is formally de-featuring TSX on the older Skylake
client CPUs. The workaround from the March 2019 microcode is being dropped,
and replaced with additions to MSR_TSX_FORCE_ABORT to hide the HLE/RTM CPUID
bits.
With this microcode in place, TSX is disabled by default on these CPUs.
Backwards compatibility is provided in the same way as for TAA - RTM force
aborts, rather than suffering #UD, and the CPUID bits can be hidden to recover
performance.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 3e09045991)
The expected behavior while using xen-vmtrace is to get a clean start, even if
the tool was used previously on the same VM.
Signed-off-by: Tamas K Lengyel <tamas@tklengyel.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Add CPUID/MSR enumeration details for Processor Trace. For now, we will only
support its use inside VMX operation. Fill in the vmtrace_available boolean
to activate the newly introduced common infrastructure for allocating trace
buffers.
For now, Processor Trace is going to be operated in Single Output mode behind
the guests back. Add the MSRs to struct vcpu_msrs, and set up the buffer
limit in vmx_init_ipt() as it is fixed for the lifetime of the domain.
Context switch the most of the MSRs in and out of vCPU context, but the main
control register needs to reside in the MSR load/save lists. Explicitly pull
the msrs pointer out into a local variable, because the optimiser cannot keep
it live across the memory clobbers in the MSR accesses.
Signed-off-by: Michał Leszczyński <michal.leszczynski@cert.pl>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
memshrtool is a tool for a human to use, rather than a test. Move it into
misc/ as a more appropriate location to live. Also rename it to
xen-memshare
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
xen-access is a tool for a human to use, rather than a test. Move it
into misc/ as a more appropriate location to live.
Move the -DXC_WANT_COMPAT_DEVICEMODEL_API from CFLAGS into xen-access.c itself
to avoid adding Makefile complexity.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <ian.jackson@eu.citrix.com>
Acked-by: Tamas K Lengyel <tamas@tklengyel.com>
These are VEX-encoded equivalents of the EVEX-encoded AVX512-VNNI ISA
extension.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Relying on presence / absence of hypervisor leaves in raw / escaped
CPUID output cannot be used to tell apart PV and HVM on CPUID faulting
capable hardware. Utilize a PV-only feature flag to avoid false positive
HVM detection.
While at it also short circuit the main detection loop: For PV, only
the base group of leaves can possibly hold hypervisor information.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Switch all usages of xs_daemon_open*() and xs_domain_open() to use
xs_open() instead. While at it switch xs_daemon_close() users to
xs_close().
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
The last libxc internal used by xen-mfndump.c is the ERROR() macro.
Add a simple definition for that macro to xen-mfndump.c and replace
the libxc private header includes by official ones.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
The definition of PAGE_SIZE comes from xc_private.h, which shouldn't be
used by xen-mfndump.c. Replace PAGE_SIZE by XC_PAGE_SIZE, as
xc_private.h contains:
#define PAGE_SIZE XC_PAGE_SIZE
For the same reason PAGE_SHIFT_X86 needs to replaced with
XC_PAGE_SHIFT.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
xen-mfndump.c is including the libxc private header xg_save_restore.h.
Avoid that by moving the definition of is_mapped() to xen-mfndump.c
(it is used there only) and by duplicating the definition of
M2P_SIZE() in xen-mfndump.c.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
xen-hptool is including private headers from tools/libxc without any
need. Switch it to use official headers only.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
There are quite some places in Makefiles assuming libxenguest and
libxenctrl being built in the same directory via a single Makefile.
Drop this assumption by specifying the dependencies and path variables
for both libraries correctly.
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Also prevent warning: directory /boot: remove failed
Before:
[root@TestCloud1 xen]# rpm -hiv dist/xen*rpm
Preparing... ################################# [100%]
file /boot from install of xen-4.15-unstable.x86_64 conflicts with file from package filesystem-3.2-25.el7.x86_64
file /usr/bin from install of xen-4.15-unstable.x86_64 conflicts with file from package filesystem-3.2-25.el7.x86_64
file /usr/lib from install of xen-4.15-unstable.x86_64 conflicts with file from package filesystem-3.2-25.el7.x86_64
file /usr/lib64 from install of xen-4.15-unstable.x86_64 conflicts with file from package filesystem-3.2-25.el7.x86_64
file /usr/sbin from install of xen-4.15-unstable.x86_64 conflicts with file from package filesystem-3.2-25.el7.x86_64
[root@TestCloud1 xen]# rpm -e xen
warning: directory /boot: remove failed: Device or resource busy
After:
[root@TestCloud1 xen]# rpm -hiv dist/xen*rpm
Preparing... ################################# [100%]
Updating / installing...
1:xen-4.15-unstable ################################# [100%]
[root@TestCloud1 xen]# rpm -e xen
[root@TestCloud1 xen]#
Signed-off-by: Don Slutz <Don.Slutz@Gmail.com>
Acked-by: Wei Liu <wl@xen.org>
We've grown to a mix of dashes and underscores - switch to consistent
naming in the hope that future additions will play by this.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
The standard memory access pattern once again should allow us to go
without a test harness addition beyond the EVEX Disp8-scaling one.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Otherwise it's difficult to know if operation failed inside the automation.
While at it, also switch to returning 1 and 2 instead of errno to avoid
incompatibilies between errno and special exit code numbers.
Signed-off-by: Igor Druzhinin <igor.druzhinin@citrix.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Release-acked-by: Paul Durrant <paul@xen.org>
Reviewed-by: Igor Druzhinin <igor.druzhinin@citrix.com>
As compilers are free to choose the width of an enum they should be
avoided in stable interfaces when declaring a variable. So the
struct xenhypfs_dirent definition should be modified to have explicitly
sized members for type and encoding and the related enums should be
defined separately.
Additionally it is better to have a larger flags member in that struct
with the "writable" indicator occupying only a single bit. This will
make future additions easier.
Suggested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Release-acked-by: Paul Durrant <paul@xen.org>
asprintf() can fail, so check its return value. Additionally fix a
memory leak in xenhypfs.
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Wei Liu <wl@xen.org>
Release-acked-by: Paul Durrant <paul@xen.org>
Whenever python scripts are install, have the shebang be modified to use
whatever PYTHON_PATH is. This is useful for system where python isn't available, or
where the package build tools prevent unversioned shebang.
INSTALL_PYTHON_PROG only looks for "#!/usr/bin/env python".
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Wei Liu <wl@xen.org>
There's nothing to be done by the emulator, as we unconditionally abort
any XBEGIN.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
The CET spec has been published and guest kernels are starting to get support.
Introduce the CPUID and MSRs, and fully block the MSRs from guest use.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Wei Liu <wl@xen.org>
For now, write the same content for both. Update the users of the
initialisers to use the new name, and extend xen-cpuid to dump both default
and max featuresets.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Just as with c/s 96dc77b4b1 for XEN_SYSCTL_get_cpu_policy,
XEN_SYSCTL_get_cpu_featureset wants to become conditional.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Policy objects aren't tiny, and the derivation logic isn't trivial. We are
about to increase the number of policy objects, so will have the opportunity
to drop logic and storage space based on CONFIG_{PV,HVM}.
Start by causing XEN_SYSCTL_get_cpu_policy to fail with -EOPNOTSUPP when
requesting data for a compiled-out subsystem. Update xen-cpuid to cope and
continue to further system policies, seeing as the indicies are interleaved.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
A splitlock is an atomic operation which crosses a cache line boundary. It
serialises operations in the cache coherency fabric and comes with a
multi-thousand cycle stall.
Intel Tremont CPUs introduce MSR_CORE_CAPS to enumerate various core-specific
features, and MSR_TEST_CTRL to adjust the behaviour in the case of a
splitlock.
Virtualising this for guests is distinctly tricky owing to the fact that
MSR_TEST_CTRL has core rather than thread scope. In the meantime however,
prevent the MSR values leaking into guests.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Wei Liu <wl@xen.org>
Quoting the respective Linux commit:
Intel Xeons from Ivy Bridge onwards support a processor identification
number set in the factory. To the user this is a handy unique number to
identify a particular CPU. Intel can decode this to the fab/production
run to track errors. On systems that have it, include it in the machine
check record. I'm told that this would be helpful for users that run
large data centers with multi-socket servers to keep track of which CPUs
are seeing errors.
Newer AMD CPUs support this too, at different MSR numbers.
Take the opportunity and hide __MC_NMSRS from the public interface going
forward.
[Linux commit 3f5a7896a5096fd50030a04d4c3f28a7441e30a5]
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Extend the livepatch list operation to fetch also payloads' metadata.
This is achieved by extending the sysctl list interface with 2 extra
guest handles:
* metadata - an array of arbitrary size strings
* metadata_len - an array of metadata strings' lengths (uin32_t each)
Payloads' metadata is a string of arbitrary size and does not have an
upper bound limit. It may also vary in size between payloads.
In order to let the userland allocate enough space for the incoming
data add a metadata total size field to the list sysctl operation and
fill it with total size of all payloads' metadata.
Extend the libxc to handle the metadata back-to-back data transfers
as well as metadata length array data transfers.
The xen-livepatch userland tool is extended to always display the
metadata for each received module. The metadata is received with the
following format: key=value\0key=value\0...key=value\0. The format is
modified to the following one: key=value;key=value;...key=value.
The new format allows to easily parse the metadata for a given module
by a machine.
Signed-off-by: Pawel Wieczorkiewicz <wipawel@amazon.de>
Reviewed-by: Andra-Irina Paraschiv <andraprs@amazon.com>
Reviewed-by: Martin Pohlack <mpohlack@amazon.de>
Reviewed-by: Norbert Manthey <nmanthey@amazon.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
The payloads' name strings can be of arbitrary size (typically small
with an upper bound of XEN_LIVEPATCH_NAME_SIZE).
Current implementation of the list operation interface allows to copy
names in the XEN_LIVEPATCH_NAME_SIZE chunks regardless of its actual
size and enforces space allocation requirements on userland tools.
To unify and simplify the interface, handle the name strings of
arbitrary size by copying them in adhering chunks to the userland.
In order to let the userland allocate enough space for the incoming
data add an auxiliary interface xc_livepatch_list_get_sizes() that
provides the current number of payload entries and the total size of
all name strings. This is achieved by extending the sysctl list
interface with an extra fields: name_total_size.
The xc_livepatch_list_get_sizes() issues the livepatch sysctl list
operation with the nr field set to 0. In this mode the operation
returns the number of payload entries and calculates the total sizes
for all payloads' names.
When the sysctl operation is issued with a non-zero nr field (for
instance with a value obtained earlier with the prior call to the
xc_livepatch_list_get_sizes()) the new field name_total_size provides
the total size of actually copied data.
Extend the libxc to handle the name back-to-back data transfers.
The xen-livepatch tool is modified to start the list operation with a
call to the xc_livepatch_list_get_sizes() to obtain the actual number
of payloads as well as the necessary space for names.
The tool now always requests the actual number of entries and leaves
the preemption handling to the libxc routine. The libxc still returns
'done' and 'left' parameters with the same semantic allowing the tool
to detect anomalies and react to them. At the moment it is expected
that the tool receives the exact number of entries as requested.
The xen-livepatch tool has been also modified to handle the name
back-to-back transfers correctly.
Signed-off-by: Pawel Wieczorkiewicz <wipawel@amazon.de>
Reviewed-by: Andra-Irina Paraschiv <andraprs@amazon.com>
Reviewed-by: Bjoern Doebel <doebel@amazon.de>
Reviewed-by: Martin Pohlack <mpohlack@amazon.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Andrew Cooper
Jan Beulich
Roger Pau Monné
Tamas K Lengyel
Michał Leszczyński
Juergen Gross
Don Slutz
Olaf Hering
Igor Druzhinin
Anthony PERARD
Konrad Rzeszutek Wilk
Pawel Wieczorkiewicz