Commit Graph
290 Commits
Author SHA1 Message Date
Juergen Gross f151bb7ce4 tools/libs/ctrl: don't set errno to a negative value
The claimed reason for setting errno to -1 is wrong. On x86
xc_domain_pod_target() will set errno to a sane value in the error
case.

Fixes: ff1745d588 ("tools: libxl: do not set the PoD target on ARM")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: a0fb7e0e73
master date: 2022-04-22 20:39:34 +0100
2022-06-07 14:16:49 +02:00
Juergen Gross defa8807bf tools/libs/evtchn: don't set errno to negative values
Setting errno to a negative value makes no sense.

Fixes: 6b6500b3cb ("tools/libs/evtchn: Add support for restricting a handle")
Signed-off-by: Juergen Gross <jgross@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 60245b71c1
master date: 2022-04-22 20:39:34 +0100
2022-06-07 14:16:30 +02:00
Jason Andryuk 7b181e559a libxl: Re-scope qmp_proxy_spawn.ao usage
I've observed this failed assertion:
libxl_event.c:2057: libxl__ao_inprogress_gc: Assertion `ao' failed.

AFAICT, this is happening in qmp_proxy_spawn_outcome where
sdss->qmp_proxy_spawn.ao is NULL.

The out label of spawn_stub_launch_dm() calls qmp_proxy_spawn_outcome(),
but it is only in the success path that sdss->qmp_proxy_spawn.ao gets
set to the current ao.

qmp_proxy_spawn_outcome() should instead use sdss->dm.spawn.ao, which is
the already in-use ao when spawn_stub_launch_dm() is called.  The same
is true for spawn_qmp_proxy().

With this, move sdss->qmp_proxy_spawn.ao initialization to
spawn_qmp_proxy() since its use is for libxl__spawn_spawn() and it can
be initialized along with the rest of sdss->qmp_proxy_spawn.

Fixes: 83c845033d ("libxl: use vchan for QMP access with Linux stubdomain")
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
master commit: d62a34423a
master date: 2022-04-01 17:01:57 +0100
2022-04-06 10:23:32 +02:00
Jason Andryuk d9b39c308d libxl: Don't segfault on soft-reset failure
If domain_soft_reset_cb can't rename the save file, it doesn't call
initiate_domain_create() and calls domcreate_complete().

Skipping initiate_domain_create() means dcs->console_wait is
uninitialized and all 0s.

We have:
  domcreate_complete()
    libxl__xswait_stop()
      libxl__ev_xswatch_deregister().

The uninitialized slotnum 0 is considered valid (-1 is the invalid
sentinel), so the NULL pointer path to passed to xs_unwatch() which
segfaults.

libxl__ev_xswatch_deregister:watch w=0x12bc250 wpath=(null) token=0/0: deregister slotnum=0

Move dcs->console_xswait initialization into the callers of
initiate_domain_create, do_domain_create() and do_domain_soft_reset(),
so it is initialized along with the other dcs state.

Fixes: c57e6ebd8c ("(lib)xl: soft reset support")
Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>

master commit: d2ecf97f91
master date: 2022-04-01 17:01:57 +0100
2022-04-06 10:23:03 +02:00
Juergen Gross 3dc39cfd72 tools/libs/light: set video_mem for PVH guests
The size of the video memory of PVH guests should be set to 0 in case
no value has been specified.

Doing not so will leave it to be -1, resulting in an additional 1 kB
of RAM being advertised in the memory map (here the output of a PVH
Mini-OS boot with 16 MB of RAM assigned):

Memory map:
000000000000-0000010003ff: RAM
0000feff8000-0000feffffff: Reserved
0000fc008000-0000fc00803f: ACPI
0000fc000000-0000fc000fff: ACPI
0000fc001000-0000fc007fff: ACPI

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Roger Pau Monné <roger.pau@citrix.com>
Acked-by: Anthony PERARD <anthony.perard@citrix.com>
master commit: 0a20a53df1
master date: 2021-12-09 16:26:29 +0000
2022-04-06 10:21:44 +02:00
Roger Pau Monné ef27037d43 tools/libxl: don't allow IOMMU usage with PoD
Prevent libxl from creating guests that attempts to use PoD together
with an IOMMU, even if no devices are actually assigned.

While the hypervisor could support using PoD together with an IOMMU as
long as no devices are assigned, such usage seems doubtful. There's no
guarantee the guest has PoD no longer be active, and thus a later
assignment of a PCI device to such domain could fail.

Preventing the usage of PoD together with an IOMMU at guest creation
avoids having to add checks for active PoD entries in the device
assignment paths.

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
master commit: 07449ecfa4
master date: 2022-02-18 09:03:08 +0100
2022-03-10 09:50:44 +01:00
Anthony PERARD 3bf48e5325 tools/libs: Fix build dependencies
Some libs' Makefile aren't loading the dependencies files *.d2.

We can load them from "libs.mk" as none of the Makefile here are
changing $(DEPS) or $(DEPS_INCLUDE) so it is fine to move the
"include" to "libs.mk".

As a little improvement, don't load the dependencies files (and thus
avoid regenerating the *.d2 files) during `make clean`.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
master commit: e62cc29f9b
master date: 2022-02-08 11:15:53 +0000
2022-02-16 16:03:56 +01:00
Dario Faggioli ef47070bbb tools/libs/light: don't touch nr_vcpus_out if listing vcpus and returning NULL
If we are in libxl_list_vcpu() and we are returning NULL, let's avoid
touching the output parameter *nr_vcpus_out, which the caller should
have initialized to 0.

The current behavior could be problematic if are creating a domain and,
in the meantime, an existing one is destroyed when we have already done
some steps of the loop. At which point, we'd return a NULL list of vcpus
but with something different than 0 as the number of vcpus in that list.
And this can cause troubles in the callers (e.g., nr_vcpus_on_nodes()),
when they do a libxl_vcpuinfo_list_free().

Crashes due to this are rare and difficult to reproduce, but have been
observed, with stack traces looking like this one:

#0  libxl_bitmap_dispose (map=map@entry=0x50) at libxl_utils.c:626
#1  0x00007fe72c993a32 in libxl_vcpuinfo_dispose (p=p@entry=0x38) at _libxl_types.c:692
#2  0x00007fe72c94e3c4 in libxl_vcpuinfo_list_free (list=0x0, nr=<optimized out>) at libxl_utils.c:1059
#3  0x00007fe72c9528bf in nr_vcpus_on_nodes (vcpus_on_node=0x7fe71000eb60, suitable_cpumap=0x7fe721df0d38, tinfo_elements=48, tinfo=0x7fe7101b3900, gc=0x7fe7101bbfa0) at libxl_numa.c:258
#4  libxl__get_numa_candidate (gc=gc@entry=0x7fe7100033a0, min_free_memkb=4233216, min_cpus=4, min_nodes=min_nodes@entry=0, max_nodes=max_nodes@entry=0, suitable_cpumap=suitable_cpumap@entry=0x7fe721df0d38, numa_cmpf=0x7fe72c940110 <numa_cmpf>, cndt_out=0x7fe721df0cf0, cndt_found=0x7fe721df0cb4) at libxl_numa.c:394
#5  0x00007fe72c94152b in numa_place_domain (d_config=0x7fe721df11b0, domid=975, gc=0x7fe7100033a0) at libxl_dom.c:209
#6  libxl__build_pre (gc=gc@entry=0x7fe7100033a0, domid=domid@entry=975, d_config=d_config@entry=0x7fe721df11b0, state=state@entry=0x7fe710077700) at libxl_dom.c:436
#7  0x00007fe72c92c4a5 in libxl__domain_build (gc=0x7fe7100033a0, d_config=d_config@entry=0x7fe721df11b0, domid=975, state=0x7fe710077700) at libxl_create.c:444
#8  0x00007fe72c92de8b in domcreate_bootloader_done (egc=0x7fe721df0f60, bl=0x7fe7100778c0, rc=<optimized out>) at libxl_create.c:1222
#9  0x00007fe72c980425 in libxl__bootloader_run (egc=egc@entry=0x7fe721df0f60, bl=bl@entry=0x7fe7100778c0) at libxl_bootloader.c:403
#10 0x00007fe72c92f281 in initiate_domain_create (egc=egc@entry=0x7fe721df0f60, dcs=dcs@entry=0x7fe7100771b0) at libxl_create.c:1159
#11 0x00007fe72c92f456 in do_domain_create (ctx=ctx@entry=0x7fe71001c840, d_config=d_config@entry=0x7fe721df11b0, domid=domid@entry=0x7fe721df10a8, restore_fd=restore_fd@entry=-1, send_back_fd=send_back_fd@entry=-1, params=params@entry=0x0, ao_how=0x0, aop_console_how=0x7fe721df10f0) at libxl_create.c:1856
#12 0x00007fe72c92f776 in libxl_domain_create_new (ctx=0x7fe71001c840, d_config=d_config@entry=0x7fe721df11b0, domid=domid@entry=0x7fe721df10a8, ao_how=ao_how@entry=0x0, aop_console_how=aop_console_how@entry=0x7fe721df10f0) at libxl_create.c:2075

Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
Tested-by: James Fehlig <jfehlig@suse.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
master commit: d9d3496e81
master date: 2022-01-31 10:58:07 +0100
2022-02-16 16:02:58 +01:00
Roger Pau Monné 59a5fbd6fe libxl: force netback to wait for hotplug execution before connecting
By writing an empty "hotplug-status" xenstore node in the backend path
libxl can force Linux netback to wait for hotplug script execution
before proceeding to the 'connected' state.

This is required so that netback doesn't skip state 2 (InitWait) and
thus blocks libxl waiting for such state in order to launch the
hotplug script (see libxl__wait_device_connection).

Reported-by: James Dingwall <james-xen@dingwall.me.uk>
Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Tested-by: James Dingwall <james-xen@dingwall.me.uk>
Reviewed-by: Paul Durrant <paul@xen.org>
Tested-by: Julien Grall <jgrall@amazon.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
master commit: 0bdc43c8de
master date: 2022-01-27 13:51:19 +0100
2022-02-16 16:02:34 +01:00
Kevin Stefanov 11eedbb0bb tools/libxl: Correctly align the ACPI tables
The memory allocator currently calculates alignment in libxl's virtual
address space, rather than guest physical address space. This results
in the FACS being commonly misaligned.

Furthermore, the allocator has several other bugs.

The opencoded align-up calculation is currently susceptible to a bug
that occurs in the corner case that the buffer is already aligned to
begin with. In that case, an align-sized memory hole is introduced.

The while loop is dead logic because its effects are entirely and
unconditionally overwritten immediately after it.

Rework the memory allocator to align in guest physical address space
instead of libxl's virtual memory and improve the calculation, drop
errant extra page in allocated buffer for ACPI tables, and give some
of the variables better names/types.

Fixes: 14c0d328da ("libxl/acpi: Build ACPI tables for HVMlite guests")
Signed-off-by: Kevin Stefanov <kevin.stefanov@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
master commit: dd6c062a7a
master date: 2021-09-24 11:07:50 +0100
2022-02-16 16:02:12 +01:00
Andrew Cooper 1ec097c35c x86/spec-ctrl: Support Intel PSFD for guests
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)
2022-02-08 18:04:52 +00:00
Roger Pau Monné 0d89d04f63 x86/cpuid: support LFENCE always serialising CPUID bit
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)
2022-02-04 16:26:49 +00:00
Jason Andryuk 7ca8706ad5 libxl/PCI: Fix PV hotplug & stubdom coldplug
commit 0fdb48ffe7 "libxl: Make sure devices added by pci-attach are
reflected in the config" broken PCI hotplug (xl pci-attach) for PV
domains when it moved libxl__create_pci_backend() later in the function.

This also broke HVM + stubdom PCI passthrough coldplug.  For that, the
PCI devices are hotplugged to a running PV stubdom, and then the QEMU
QMP device_add commands are made to QEMU inside the stubdom.

A running PV domain calls libxl__wait_for_backend().  With the current
placement of libxl__create_pci_backend(), the path does not exist and
the call immediately fails:
libxl: error: libxl_device.c:1388:libxl__wait_for_backend: Backend /local/domain/0/backend/pci/43/0 does not exist
libxl: error: libxl_pci.c:1764:device_pci_add_done: Domain 42:libxl__device_pci_add failed for PCI device 0:2:0.0 (rc -3)
libxl: error: libxl_create.c:1857:domcreate_attach_devices: Domain 42:unable to add pci devices

The wait is only relevant when:
1) The domain is PV
2) The domain is running
3) The backend is already present

This is because:

1) xen-pcifront is only used for PV.  It does not load for HVM domains
   where QEMU is used.

2) If the domain is not running (starting), then the frontend state will
   be Initialising.  xen-pciback waits for the frontend to transition to
   at Initialised before attempting to connect.  So a wait for a
   non-running domain is not applicable as the backend will not
   transition to Connected.

3) For presence, num_devs is already used to determine if the backend
   needs to be created.  Re-use num_devs to determine if the backend
   wait is necessary.  The wait is necessary to avoid racing with
   another PCI attachment reconfiguring the front/back or changing to
   some other state like closing.  If we are creating the backend, then
   we don't have to worry about the state since it is being created.

Fixes: 0fdb48ffe7 ("libxl: Make sure devices added by pci-attach are
reflected in the config")

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
master commit: 73ee2795aa
master date: 2022-01-13 14:33:16 +0100
2022-01-25 13:45:09 +01:00
Andrew Cooper c8260b3d38 x86/cpuid: Fix TSXLDTRK definition
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
2022-01-07 08:15:05 +01:00
Andrew Cooper 932ff4385a x86/amd: Enumeration for speculative features/hints
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
2021-10-15 11:00:53 +02:00
Jan Beulich 6bbdcefd20 libxl/x86: check return value of SHADOW_OP_SET_ALLOCATION domctl
The hypervisor may not have enough memory to satisfy the request. While
there, make the unit of the value clear by renaming the local variable.

Requested-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Anthony PERARD <anthony.perard@citrix.com>
backport-requested-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 0be5a00af5)
2021-08-19 17:46:59 +01:00
Jan Beulich abfbb29830 libxc: use multicall for memory-op on Linux (and Solaris)
Some sub-functions, XENMEM_maximum_gpfn and XENMEM_maximum_ram_page in
particular, can return values requiring more than 31 bits to represent.
Hence we cannot issue the hypercall directly when the return value of
ioctl() is used to propagate this value. This is the case for Linux
and Solaris (and hence needs changing), while the BSDs avoid using the
return value for dual purposes altogether, and MiniOS already wraps all
hypercalls in a multicall.

Suggested-by: Jürgen Groß <jgross@suse.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Backport-requested-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 6f02d1ea4a)
2021-08-19 17:33:40 +01:00
Andrew Cooper c3cf33b071 libxencall: Bump SONAME following new functionality
Fixes: bef64f2c00 ("libxencall: introduce variant of xencall2() returning long")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Backport-requested-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 01a2d001de)
2021-08-19 17:33:40 +01:00
Jan Beulich e0da171fc1 libxencall: introduce variant of xencall2() returning long
Some hypercalls, memory-op in particular, can return values requiring
more than 31 bits to represent. Hence the underlying layers need to make
sure they won't truncate such values.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Backport-requested-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit bef64f2c00)
2021-08-19 17:33:40 +01:00
Jan Beulich c773053bdb libxencall: osdep_hypercall() should return long
Some hypercalls, memory-op in particular, can return values requiring
more than 31 bits to represent. Hence the underlying layers need to make
sure they won't truncate such values. (Note that for Solaris the
function also gets renamed, to match the other OSes.)

Due to them merely propagating ioctl()'s return value, this change is
benign on Linux and Solaris. IOW there's an actual effect here only for
the BSDs and MiniOS, but even then further adjustments are needed at the
xencall<N>() level.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
Backport-requested-by: Jan Beulich <jbeulich@suse.com>
(cherry picked from commit 6409210a5f)
2021-08-19 17:33:40 +01:00
Anthony PERARD 00bd594d6c libxl: Fix QEMU cmdline for scsi device
Usage of 'scsi-disk' device is deprecated and removed from QEMU,
instead we need to use 'scsi-hd' for hard drives.
See QEMU 879be3af49 (hw/scsi: remove 'scsi-disk' device)

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
(cherry picked from commit 3bc3be978f)

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:19:48 +01:00
Anthony PERARD 0e419e446f libxl: Replace short-form boolean for QEMU's -vnc
f3f778c817 forgot one boolean parameter.

Fixes: f3f778c817 ("libxl: Replace QEMU's command line short-form boolean option")
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
(cherry picked from commit 217eef30f7)

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:19:38 +01:00
Anthony PERARD e3f5318546 libxl: Replace QMP command "change" by "blockdev-change-media"
"change" command as been removed in QEMU 6.0. We can use
"blockdev-change-medium" instead.

Using `id` with "blockdev-change-medium" requires a change to the QEMU
command line, introduced by:
    "libxl: Use -device for cd-rom drives"

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:18:17 +01:00
Anthony PERARD 4b60715241 libxl: Use id with the "eject" QMP command
`device` parameter is deprecated since QEMU 2.8.

This requires changes to the command line introduced by:
    "libxl: Use -device for cd-rom drives"

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:18:15 +01:00
Anthony PERARD e949445ce9 libxl: Export libxl__qmp_ev_qemu_compare_version
We are going to want to check QEMU's version in other places where we
can use libxl__ev_qmp_send.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:18:12 +01:00
Anthony PERARD 9cb597a545 libxl: Assert qmp_ev's state in qmp_ev_qemu_compare_version
We are supposed to read the version information only when qmp_ev is in
state "Connected" (that correspond to state==qmp_state_connected),
assert it so that the function isn't used too early.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:18:09 +01:00
Anthony PERARD 6165dcfe7e libxl: Use -device for cd-rom drives
This allows to set an `id` on the device instead of only the drive. We
are going to need the `id` with the "eject" and
"blockdev-change-media" QMP command as using `device` parameter on
those is deprecated. (`device` is the `id` of the `-drive` on the
command line).

We set the same `id` on both -device and -drive as QEMU doesn't
complain and we can then either do "eject id=$id" or "eject
device=$id".

Using "-drive + -device" instead of only "-drive" has been
available since at least QEMU 0.15, and seems to be the preferred way as it
separates the host part (-drive which describe the disk image location
and format) from the guest part (-device which describe the emulated
device). More information in qemu.git/docs/qdev-device-use.txt .

Changing the command line during migration for the cdrom seems fine.
Also the documentation about migration in QEMU explains that the device
state ID is "been formed from a bus name and device address", so
second IDE bus and first device address on bus is still thus and
doesn't matter if written "-drive if=ide,index=2" or "-drive
ide-cd,bus=ide.1,unit=0".
See qemu.git/docs/devel/migration.rst .

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:18:07 +01:00
Anthony PERARD da659f61c7 libxl: Replace deprecated "cpu-add" QMP command by "device_add"
The command "cpu-add" for CPU hotplug is deprecated and has been
removed from QEMU 6.0 (April 2021). We need to add cpus with the
command "device_add" now.

In order to find out which parameters to pass to "device_add" we first
make a call to "query-hotpluggable-cpus" which list the cpus drivers
and properties.

The algorithm to figure out which CPU to add, and by extension if any
CPU needs to be hotplugged, is in the function that adds the cpus.
Because of that, the command "query-hotpluggable-cpus" is always
called, even when not needed.

In case we are using a version of QEMU older than 2.7 (Sept 2016)
which don't have "query-hotpluggable-cpus", we fallback to using
"cpu-add".

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:18:04 +01:00
Anthony PERARD 17dca162e0 libxl: Replace QEMU's command line short-form boolean option
Short-form boolean options are deprecated in QEMU 6.0.
Upstream commit that deprecate those: ccd3b3b8112b ("qemu-option: warn
for short-form boolean options").

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>
2021-08-19 17:17:43 +01:00
Anthony PERARD 99633c514d libxl: Replace deprecated QMP command by "query-cpus-fast"
We use the deprecated QMP command "query-cpus" which is removed in the
QEMU 6.0 release. There's a replacement which is "query-cpus-fast",
and have been available since QEMU 2.12 (April 2018).

This patch try the new command first and when the command isn't
available, it fall back to the deprecated one so libxl still works
with older QEMU versions.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jason Andryuk <jandryuk@gmail.com>

Backport-requested-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:16:41 +01:00
Juergen Gross 2b23bb664f tools/libs/ctrl: fix xc_core_arch_map_p2m() to support linear p2m table
The core of a pv linux guest produced via "xl dump-core" is not usable
as since kernel 4.14 only the linear p2m table is kept if Xen indicates
it is supporting that. Unfortunately xc_core_arch_map_p2m() is still
supporting the 3-level p2m tree only.

Fix that by copying the functionality of map_p2m() from libxenguest to
libxenctrl.

Additionally the mapped p2m isn't of a fixed length now, so the
interface to the mapping functions needs to be adapted. In order not to
add even more parameters, expand struct domain_info_context and use a
pointer to that as a parameter.

This is a backport of upstream commit bd7a29c3d0.

As the original patch includes a modification of a data structure
passed via pointer to a library function, the related function in the
library is renamed in order to be able to spot any external users of
that function. Note that it is extremely unlikely any such users
outside the Xen git tree are existing, so the risk to break any
existing programs is very unlikely. In case such a user is existing,
changing the name of xc_map_domain_meminfo() will at least avoid
silent breakage.

Fixes: dc6d609371 ("libxc: set flag for support of linear p2m list in domain builder")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
2021-08-19 17:12:10 +01:00
Richard Kojedzinszky 429b0a5c62 tools/libxenstat: fix populating vbd.rd_sect
Fixes: 91c3e3dc91 ("tools/xentop: Display '-' when stats are not available.")
Signed-off-by: Richard Kojedzinszky <richard@kojedz.in>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
(cherry picked from commit 89d57f291e)
2021-07-15 11:55:50 +01:00
Anthony PERARD d8a530ebc3 libs/foreignmemory: Fix osdep_xenforeignmemory_map prototype
Commit cf8c4d3d13 made some preparation to have one day
variable-length-array argument, but didn't declare the array in the
function prototype the same way as in the function definition. And now
GCC 11 complains about it.

Fixes: cf8c4d3d13 ("tools/libs/foreignmemory: pull array length argument to map forward")
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
master commit: 5d3e4ebb5c
master date: 2021-06-15 18:07:58 +0100
2021-07-15 09:20:10 +02:00
George Dunlap 77069ea825 SUPPORT.md: Un-shimmed 32-bit PV guests are no longer supported
The support status of 32-bit guests doesn't seem particularly useful.

With it changed to fully unsupported outside of PV-shim, adjust the PV32
Kconfig default accordingly.

Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: George Dunlap <george.dunlap@citrix.com>
Signed-off-by: Jan Beulich <jbeulich@suse.com>

tools/libs/guest: fix save and restore of pv domains after 32-bit de-support

After 32-bit PV-guests have been security de-supported when not running
under PV-shim, the hypervisor will no longer be configured to support
those domains per default when not being built as PV-shim.

Unfortunately libxenguest will fail saving or restoring a PV domain
due to this restriction, as it is trying to get the compat MFN list
even for 64 bit guests.

Fix that by obtaining the compat MFN list only for 32-bit PV guests.

Fixes: 1a0f2fe229 ("SUPPORT.md: Un-shimmed 32-bit PV guests are no longer supported")
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
master commit: 1a0f2fe229
master date: 2021-06-04 17:24:05 +0100
master commit: d21121685f
master date: 2021-06-07 15:43:35 +0100
2021-07-15 09:16:02 +02:00
Andrew Cooper 89c6e84f6d x86/cpuid: Rework HLE and RTM handling
The TAA mitigation offered the option to hide the HLE and RTM CPUID bits,
which has caused some migration compatibility problems.

These two bits are special.  Annotate them with ! to emphasise this point.

Hardware Lock Elision (HLE) may or may not be visible in CPUID, but is
disabled in microcode on all CPUs, and has been removed from the architecture.
Do not advertise it to VMs by default.

Restricted Transactional Memory (RTM) may or may not be visible in CPUID, and
may or may not be configured in force-abort mode.  Have tsx_init() note
whether RTM has been configured into force-abort mode, so
guest_common_feature_adjustments() can conditionally hide it from VMs by
default.

The host policy values for HLE/RTM may or may not be set, depending on any
previous running kernel's choice of visibility, and Xen's choice.  TSX is
available on any CPU which enumerates a TSX-hiding mechanism, so instead of
doing a two-step to clobber any hiding, scan CPUID, then set the visibility,
just force visibility of the bits in the first place.

With the HLE/RTM bits now unilaterally visible in the host policy,
xc_cpuid_apply_policy() can construct a more appropriate policy out of thin
air for pre-4.13 VMs with no CPUID data in their migration stream, and
specifically one where HLE/RTM doesn't potentially disappear behind the back
of a running VM.

Fixes: 8c4330818f ("x86/spec-ctrl: Mitigate the TSX Asynchronous Abort sidechannel")
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>
master commit: 8fe24090d9
master date: 2021-05-27 19:34:00 +0100
2021-06-04 14:49:05 +02:00
Anthony PERARD dae3c3e8b2 libxl: Fix domain soft reset state handling
In do_domain_soft_reset(), a `libxl__domain_suspend_state' is used
without been properly initialised and disposed of. This lead do a
abort() in libxl due to the `dsps.qmp' state been used before been
initialised:
    libxl__ev_qmp_send: Assertion `ev->state == qmp_state_disconnected || ev->state == qmp_state_connected' failed.

Once initialised, `dsps' also needs to be disposed of as the `qmp'
state might still be in the `Connected' state in the callback for
libxl__domain_suspend_device_model(). So this patch adds
libxl__domain_suspend_dispose() which can be called from the two
places where we need to dispose of `dsps'.

Reported-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Tested-by: Olaf Hering <olaf@aepfle.de>
2021-03-18 14:56:33 +01:00
Roger Pau Monné 0570d7f276 x86/msr: introduce an option for compatible MSR behavior selection
Introduce an option to allow selecting a behavior similar to the pre
Xen 4.15 one for accesses to MSRs not explicitly handled. Since commit
84e848fd7a and 322ec7c89f accesses to MSRs not explicitly
handled by Xen result in the injection of a #GP to the guest. This
is a behavior change since previously a #GP was only injected if
accessing the MSR on the real hardware would also trigger a #GP, or if
the attempted to be set bits wouldn't match the hardware values (for
PV). The reasons for not leaking hardware MSR values and injecting a
#GP are fully valid, so the solution proposed here should be
considered a temporary workaround until all the required MSRs are
properly handled.

This seems to be problematic for some guests, so introduce an option
to fallback to this kind of legacy behavior without leaking the
underlying MSR values to the guest.

When the option is set, for both PV and HVM don't inject a #GP to the
guest on MSR read if reading the underlying MSR doesn't result in a
#GP, do the same for writes and simply discard the value to be written
on that case.

Note that for guests restored or migrated from previous Xen versions
the option is enabled by default, in order to keep a compatible
MSR behavior. Such compatibility is done at the libxl layer, to avoid
higher-level toolstacks from having to know the details about this flag.

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>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-03-12 08:59:56 +01:00
Andrew Cooper 9e23f10eb0 tools/libs: Fix headers.chk logic
c/s 4664034cd dropped the $(LIBHEADERSGLOB) dependency for the headers.chk
rule, without replacing it.

As headers.chk uses $^, a typical build looks like:

  andrewcoop@andrewcoop:/local/xen.git$ make -C tools/libs/devicemodel/
  make: Entering directory '/local/xen.git/tools/libs/devicemodel'
  for i in ; do \
      gcc -x c -ansi -Wall -Werror -I/local/xen.git/tools/libs/devicemodel/../../../tools/include \
            -S -o /dev/null $i || exit 1; \
      echo $i; \
  done >headers.chk.new
  mv headers.chk.new headers.chk

i.e. with an empty for loop.

Reinsert a $(LIBHEADERS) dependency, so more than just the $(AUTOINCS) get
checked.

Fixes: 4664034cd ("tools/libs: move official headers to common directory")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-03-11 17:27:48 +00:00
Andrew Cooper 368096b9c4 xen/dmop: Strip __XEN_TOOLS__ header guard from public ABI
__XEN_TOOLS__ is really there to separate the unstable from stable hypercalls.
Exactly as with c/s f40e1c52e4, stable interfaces shouldn't contain this
guard.

That change actually broke the build with:

  include/xendevicemodel.h:52:5: error: unknown type name 'ioservid_t'
       ioservid_t *id);
       ^

as libxendevicemodel.h now uses a type it can't see a typedef for.  However,
nothing noticed because the header.chk logic is also broken (fixed
subsequently).

Strip the guard from the public header, and remove compensation from
devicemodel's private.h.  Fix the dmop design doc to discuss both reasons
behind the the ABI design.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-03-11 17:27:48 +00:00
Andrew Cooper 67390ec1f7 tools/libxentoolcore: Fill in LIBHEADERS
c/s 4664034cd replaced a glob over include/*.h with an expectation that
LIBHEADER was suitably set for libraries which didn't have a single,
consistently named, header file.

This wasn't true for xentoolcore, which lost xentoolcore_internal.h as a
consequence, and failed an API/ABI check vs 4.14

Fixes: 4664034cd ("tools/libs: move official headers to common directory")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-03-11 17:27:48 +00:00
Jan Beulich 1b47cc852f libxl/ACPI: add missing build dependency
Just like all other object files - wherever *.o is mentioned, *.opic
also needs mentioning to yield consistent behavior. Otherwise make may
decide to (re)build the object before recursion into $(ACPI_PATH)/ (to
update $(DSDT_FILES-y) and ssdt_*.h) was actually finished.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-03-09 18:04:07 +01:00
Norbert Manthey 243036df0d tools/xenstore: Harden xs_domain_is_introduced()
The function single_with_domid() may return NULL if something
went wrong (e.g. XenStored returns an error or the connection is
in bad state).

They are unlikely but not impossible, so it would be better to
return an error and allow the caller to handle it gracefully rather
than crashing.

In this case we should treat it as the domain has disappeared (i.e.
return false) as the caller will not likely going to be able to
communicate with XenStored again.

This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc.

Signed-off-by: Norbert Manthey <nmanthey@amazon.de>
Reviewed-by: Julien Grall <jgrall@amazon.co.uk>
Reviewed-by: Raphael Ning <raphning@amazon.co.uk>
Reviewed-by: Juergen Gross <jgross@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-03-03 18:22:06 +00:00
Andrew Cooper c4441ab1f1 dmop: Add XEN_DMOP_nr_vcpus
Curiously absent from the stable API/ABIs is an ability to query the number of
vcpus which a domain has.  Emulators need to know this information in
particular to know how many stuct ioreq's live in the ioreq server mappings.

In practice, this forces all userspace to link against libxenctrl to use
xc_domain_getinfo(), which rather defeats the purpose of the stable libraries.

Introduce a DMOP to retrieve this information and surface it in
libxendevicemodel to help emulators shed their use of unstable interfaces.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
---
CC: Jan Beulich <JBeulich@suse.com>
CC: Roger Pau Monné <roger.pau@citrix.com>
CC: Wei Liu <wl@xen.org>
CC: Paul Durrant <paul@xen.org>
CC: Stefano Stabellini <sstabellini@kernel.org>
CC: Julien Grall <julien@xen.org>
CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
CC: Ian Jackson <iwj@xenproject.org>

For 4.15.  This was a surprise discovery in the massive ABI untangling effort
I'm currently doing for XenServer's new build system.

This is one new read-only op to obtain information which isn't otherwise
available under a stable API/ABI.  As such, its risk for 4.15 is very low,
with a very real quality-of-life improvement for downstreams.

I realise this is technically a new feature and we're long past feature
freeze, but I'm hoping that "really lets some emulators move off the unstable
libraries" is sufficiently convincing argument.

It's not sufficient to let Qemu move off unstable libraries yet - at a
minimum, the add_to_phymap hypercalls need stabilising to support PCI
Passthrough and BAR remapping.

I'd prefer not to duplicate the op handling between ARM and x86, and if this
weren't a release window, I'd submit a prereq patch to dedup the common dmop
handling.  That can wait to 4.16 at this point.  Also, this op ought to work
against x86 PV guests, but fixing that up will also need this rearrangement
into common code, so needs to wait.
2021-02-26 12:28:52 +00:00
Juergen Gross 87a067fd8f tools/libs/light: fix xl save -c handling
libxl_domain_resume() won't work correctly for the case it was called
due to a "xl save -c" command, i.e. to continue the suspended domain.

The information to do that is not saved in libxl__dm_resume_state for
non-HVM domains.

Fixes: 6298f0eb8f ("libxl: Re-introduce libxl__domain_resume")
Reported-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Tested-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Acked-by: Wei Liu <wl@xen.org>
2021-02-19 17:52:41 +00:00
Andrew Cooper d7c9f7a7a3 tools/libs: Write out an ABI analysis when abi-dumper is available
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-02-19 17:10:33 +00:00
Andrew Cooper 0670834c50 tools/libs: Add rule to generate headers.lst
abi-dumper needs a list of the public header files for shared objects, and
only accepts this in the form of a file.

No functional change.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-02-19 17:10:33 +00:00
Andrew Cooper 2ff2adc61f tools/libxl: Work around unintialised variable libxl__domain_get_device_model_uid()
Various version of gcc, when compiling with -Og, complain:

  libxl_dm.c: In function 'libxl__domain_get_device_model_uid':
  libxl_dm.c:256:12: error: 'kill_by_uid' may be used uninitialized in this function [-Werror=maybe-uninitialized]
    256 |         if (kill_by_uid)
        |            ^

The logic is very tangled.  Set kill_by_uid on every path.

No funcational change.

Requested-by: Ian Jackson <iwj@xenproject.org>
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Not-acked-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-02-19 17:10:33 +00:00
Andrew Cooper b4159d2de0 tools/libxl: Fix uninitialised variable in libxl__write_stub_dmargs()
Various version of gcc, when compiling with -Og, complain:

  libxl_dm.c: In function ‘libxl__write_stub_dmargs’:
  libxl_dm.c:2166:16: error: ‘dmargs’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
               rc = libxl__xs_write_checked(gc, t, path, dmargs);
               ~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

It isn't actually used while uninitialised, but only because of how the
is_linux_stubdom checks line up.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Ian Jackson <iwj@xenproject.org>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-02-17 12:37:08 +00:00
Andrew Cooper 928bffb6dd tools/libxg: Drop stale p2m logic from ARM's meminit()
Various version of gcc, when compiling with -Og, complain:

  xg_dom_arm.c: In function 'meminit':
  xg_dom_arm.c:420:19: error: 'p2m_size' may be used uninitialized in this function [-Werror=maybe-uninitialized]
    420 |     dom->p2m_size = p2m_size;
        |     ~~~~~~~~~~~~~~^~~~~~~~~~

This is actually entirely stale code since ee21f10d70^..97e34ad22d which
removed the 1:1 identity p2m for translated domains.

Drop the write of d->p2m_size, and the p2m_size local variable.  Reposition
the p2m_size field in struct xc_dom_image and correct some stale
documentation.

This change really ought to have been part of the original cleanup series.

No actual change to how ARM domains are constructed.

Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Julien Grall <jgrall@amazon.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-02-17 12:37:08 +00:00
Andrew Cooper 6077353223 tools/libxg: Fix uninitialised variable in write_x86_cpu_policy_records()
Various version of gcc, when compiling with -Og, complain:

  xg_sr_common_x86.c: In function 'write_x86_cpu_policy_records':
  xg_sr_common_x86.c:92:12: error: 'rc' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     92 |     return rc;
        |            ^~

The complaint is legitimate, and can occur with unexpected behaviour of two
related hypercalls in combination with a libc which permits zero-length
malloc()s.

Have an explicit rc = 0 on the success path, and make the MSRs record error
handling consistent with the CPUID record before it.

Fixes: f6b2b8ec53 ("libxc/save: Write X86_{CPUID,MSR}_DATA records")
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Reviewed-by: Jan Beulich <jbeulich@suse.com>
Release-Acked-by: Ian Jackson <iwj@xenproject.org>
2021-02-17 12:37:08 +00:00