If COW areas of the newly allocated clusters are zeroes on the backing
image, efficient bdrv_write_zeroes(flags=BDRV_REQ_NO_FALLBACK) can be
used on the whole cluster instead of writing explicit zero buffers later
in perform_cow().

iotest 060:
write to the discarded cluster does not trigger COW anymore.
Use a backing image instead.

Signed-off-by: Anton Nefedov <anton.nefedov@virtuozzo.com>
Message-id: 20190516142749.81019-2-anton.nefedov@virtuozzo.com
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

If a chain was detected, don't open a new BlockBackend from the target
backing file which will create a new BlockDriverState. Instead, create
an empty BlockBackend and attach the already open BlockDriverState.

Permissions for blk_new() were copied from blk_new_open() when
flags = 0.

Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Eyal Moscovici <eyal.moscovici@oracle.com>
Signed-off-by: Sagi Amit <sagi.amit@oracle.com>
Co-developed-by: Sagi Amit <sagi.amit@oracle.com>
Signed-off-by: Sam Eiderman <shmuel.eiderman@oracle.com>
Message-id: 20190523163337.4497-4-shmuel.eiderman@oracle.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

In the following case:

(base) A <- B <- C (tip)

when running:

    qemu-img rebase -b A C

QEMU would read all sectors not allocated in the file being rebased (C)
and compare them to the new base image (A), regardless of whether they
were changed or even allocated anywhere along the chain between the new
base and the top image (B). This causes many unneeded reads when
rebasing an image which represents a small diff of a large disk, as it
would read most of the disk's sectors.

Instead, use bdrv_is_allocated_above() to reduce the number of
unnecessary reads.

Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Signed-off-by: Sam Eiderman <shmuel.eiderman@oracle.com>
Signed-off-by: Eyal Moscovici <eyal.moscovici@oracle.com>
Message-id: 20190523163337.4497-3-shmuel.eiderman@oracle.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

In safe mode we open the entire chain, including the parent backing
file of the rebased file.
Do not open a new BlockBackend for the parent backing file, which
saves opening the rest of the chain twice, which for long chains
saves many "pricy" bdrv_open() calls.

Permissions for blk_new() were copied from blk_new_open() when
flags = 0.

Reviewed-by: Karl Heubaum <karl.heubaum@oracle.com>
Reviewed-by: Eyal Moscovici <eyal.moscovici@oracle.com>
Signed-off-by: Sagi Amit <sagi.amit@oracle.com>
Co-developed-by: Sagi Amit <sagi.amit@oracle.com>
Signed-off-by: Sam Eiderman <shmuel.eiderman@oracle.com>
Message-id: 20190523163337.4497-2-shmuel.eiderman@oracle.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

A consequence of the previous patch is that bdrv_attach_child()
transfers the reference to child_bs from the caller to parent_bs,
which will drop it on bdrv_close() or when someone calls
bdrv_unref_child().

But this only happens when bdrv_attach_child() succeeds. If it fails
then the caller is responsible for dropping the reference to child_bs.

This patch makes bdrv_attach_child() take the reference also when
there is an error, freeing the caller for having to do it.

A similar situation happens with bdrv_root_attach_child(), so the
changes on this patch affect both functions.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 20dfb3d9ccec559cdd1a9690146abad5d204a186.1557754872.git.berto@igalia.com
[mreitz: Removed now superfluous BdrvChild * variable in
         bdrv_open_child()]
Signed-off-by: Max Reitz <mreitz@redhat.com>

bdrv_unref_child() does the following things:

  - Updates the child->bs->inherits_from pointer.
  - Calls bdrv_detach_child() to remove the BdrvChild from bs->children.
  - Calls bdrv_unref() to unref the child BlockDriverState.

When bdrv_unref_child() was introduced in commit 33a60407 it was not
used in bdrv_close() because the drivers that had additional children
(like quorum or blkverify) had already called bdrv_unref() on their
children during their own close functions.

This was changed later (in 0bd6e91a for quorum, in 3e586be0 for
blkverify) so there's no reason not to use bdrv_unref_child() in
bdrv_close() anymore.

After this there's also no need to remove bs->backing and bs->file
separately from the rest of the children, so bdrv_close() can be
simplified.

Now bdrv_close() unrefs all children (before this patch it was only
bs->file and bs->backing). As a result, none of the callers of
brvd_attach_child() should remove their reference to child_bs (because
this function effectively steals that reference). This patch updates a
couple of tests that were doing their own bdrv_unref().

Signed-off-by: Alberto Garcia <berto@igalia.com>
Message-id: 6d1d5feaa53aa1ab127adb73d605dc4503e3abd5.1557754872.git.berto@igalia.com
[mreitz: s/where/were/]
Signed-off-by: Max Reitz <mreitz@redhat.com>

Split out cluster_size calculation. Move copy-bitmap creation above
block-job creation, as we are going to share it with upcoming
backup-top filter, which also should be created before actual block job
creation.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190429090842.57910-6-vsementsov@virtuozzo.com
[mreitz: Dropped a paragraph from the commit message that was left over
         from a previous version]
Signed-off-by: Max Reitz <mreitz@redhat.com>

Do full, top and incremental mode copying all in one place. This
unifies the code path and helps further improvements.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190429090842.57910-5-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Split allocation checking to separate function and reduce nesting.
Consider bdrv_is_allocated() fail as allocated area, as copying more
than needed is not wrong (and we do it anyway) and seems better than
fail the whole job. And, most probably we will fail on the next read,
if there are real problem with source.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190429090842.57910-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

We are going to share this bitmap between backup and backup-top filter
driver, so let's share something more meaningful. It also simplifies
some calculations.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190429090842.57910-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Simplify backup_incremental_init_copy_bitmap using the function
bdrv_dirty_bitmap_next_dirty_area.

Note: move to job->len instead of bitmap size: it should not matter but
less code.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190429090842.57910-2-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Do encryption/decryption in threads, like it is already done for
compression. This improves asynchronous encrypted io.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-9-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Encryption will be done in threads, to take benefit of it, we should
move it out of the lock first.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-8-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Background: decryption will be done in threads, to take benefit of it,
we should move it out of the lock first.

But let's go further: it turns out, that only
qcow2_get_cluster_offset() needs locking, so reduce locking to it.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190506142741.41731-7-vsementsov@virtuozzo.com
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>

Move generic part out of qcow2_co_do_compress, to reuse it for
encryption and rename things that would be shared with encryption path.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-6-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Drop dependence on AioContext lock.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-5-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Use thread_pool_submit_co, instead of reinventing it here. Note, that
thread_pool_submit_aio() never returns NULL, so checking it was an
extra thing.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-4-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Move compression-on-threads to separate file. Encryption will be in it
too.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-3-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

qcow2.h depends on block_int.h. Compilation isn't broken currently only
due to block_int.h always included before qcow2.h. Though, it seems
better to directly include block_int.h in qcow2.h.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190506142741.41731-2-vsementsov@virtuozzo.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

Various testing updates

  - semihosting re-factor (used in system tests)
  - aarch64 and alpha system tests
  - editorconfig tweak for .S
  - some docker image updates
  - iotests clean-up (without make check inclusion)

# gpg: Signature made Tue 28 May 2019 17:26:34 BST
# gpg:                using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-testing-next-280519-2: (27 commits)
  tests/qemu-iotests: re-format output to for make check-block
  tests/qemu-iotests/group: Re-use the "auto" group for tests that can always run
  Makefile.target: support per-target coverage reports
  Makefile: include per-target build directories in coverage report
  Makefile: fix coverage-report reference to BUILD_DIR
  .travis.yml: enable aarch64-softmmu and alpha-softmmu tcg tests
  tests/tcg/alpha: add system boot.S
  tests/tcg/multiarch: expand system memory test to cover more
  tests/tcg/minilib: support %c format char
  tests/tcg/multiarch: move the system memory test
  tests/tcg/aarch64: add system boot.S
  editorconfig: add settings for .s/.S files
  tests/tcg/multiarch: add hello world system test
  tests/tcg/multiarch: add support for multiarch system tests
  tests/docker: Test more components on the Fedora default image
  tests/docker: add ubuntu 18.04
  MAINTAINERS: update for semihostings new home
  target/mips: convert UHI_plog to use common semihosting code
  target/mips: only build mips-semi for softmmu
  target/arm: correct return values for WRITE/READ in arm-semi
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

MIPS queue for May 19th, 2019 - v3

# gpg: Signature made Sun 26 May 2019 17:07:07 BST
# gpg:                using RSA key D4972A8967F75A65
# gpg: Good signature from "Aleksandar Markovic <amarkovic@wavecomp.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 8526 FBF1 5DA3 811F 4A01  DD75 D497 2A89 67F7 5A65

* remotes/amarkovic/tags/mips-queue-may-19-2019-v3:
  BootLinuxSshTest: Test some userspace commands on Malta
  target/mips: realign comments to fix checkpatch warnings
  target/mips: add or remove space to fix checkpatch errors
  linux-user: fix __NR_semtimedop undeclared error
  mips: Decide to map PAGE_EXEC in map_address
  target/mips: Refactor and fix INSERT.<B|H|W|D> instructions
  target/mips: Refactor and fix COPY_U.<B|H|W> instructions
  target/mips: Refactor and fix COPY_S.<B|H|W|D> instructions
  target/mips: Fix MSA instructions ST.<B|H|W|D> on big endian host
  target/mips: Fix MSA instructions LD.<B|H|W|D> on big endian host
  target/mips: Make the results of MOD_<U|S>.<B|H|W|D> the same as on hardware
  target/mips: Make the results of DIV_<U|S>.<B|H|W|D> the same as on hardware

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

RISC-V Patches for the 4.1 Soft Freeze, Part 1

This tag contains a handful of patches that I'd like to target for 4.1:

* An emulation for SiFive's GPIO device.
* A fix to disallow sfence.vma from userspace.
* Additional decodetree cleanups that should have no functional impact.
* C extension emulation fidelity fixes that were noticed as part of that
  cleanup process.
* A new "spike" target, along with the deprecation of a handful of old
  targets and CPUs.
* Some initial infastructure related to the hypervisor extension.
* An emulation fidelity fix that prevents prevents arbitrary bits in the
  SIP CSR from being set.
* A small performance improvement that avoids excessive TLB flushing
  when the ASID does not change.

This time I've used a new testing workflow: I've tested on both 32-bit
and 64-bit builds of OpenEmbedded, via the default OpenSBI-based boot
flow.

# gpg: Signature made Sat 25 May 2019 01:05:57 BST
# gpg:                using RSA key 00CE76D1834960DFCE886DF8EF4CA1502CCBAB41
# gpg:                issuer "palmer@dabbelt.com"
# gpg: Good signature from "Palmer Dabbelt <palmer@dabbelt.com>" [unknown]
# gpg:                 aka "Palmer Dabbelt <palmer@sifive.com>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg:          There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 00CE 76D1 8349 60DF CE88  6DF8 EF4C A150 2CCB AB41

* remotes/palmer/tags/riscv-for-master-4.1-sf0: (29 commits)
  target/riscv: Only flush TLB if SATP.ASID changes
  target/riscv: More accurate handling of `sip` CSR
  target/riscv: Add checks for several RVC reserved operands
  target/riscv: Add the HGATP register masks
  target/riscv: Add the HSTATUS register masks
  target/riscv: Add Hypervisor CSR macros
  target/riscv: Allow setting mstatus virtulisation bits
  target/riscv: Add the MPV and MTL mstatus bits
  target/riscv: Improve the scause logic
  target/riscv: Trigger interrupt on MIP update asynchronously
  target/riscv: Mark privilege level 2 as reserved
  riscv: spike: Add a generic spike machine
  target/riscv: Deprecate the generic no MMU CPUs
  target/riscv: Add a base 32 and 64 bit CPU
  target/riscv: Create settable CPU properties
  riscv: virt: Allow specifying a CPU via commandline
  linux-user/riscv: Add the CPU type as a comment
  target/riscv: Remove unused include of riscv_htif.h for virt board riscv
  target/riscv: Remove spaces from register names
  target/riscv: Split gen_arith_imm into functional and temp
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Machine Core queue, 2019-05-24

* Display more helpful message when an object type is missing
  (Philippe Mathieu-Daudé)
* Use object_initialize_child for correct reference counting
  (Philippe Mathieu-Daudé)

# gpg: Signature made Fri 24 May 2019 19:31:06 BST
# gpg:                using RSA key 2807936F984DC5A6
# gpg: Good signature from "Eduardo Habkost <ehabkost@redhat.com>" [full]
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF  D1AA 2807 936F 984D C5A6

* remotes/ehabkost/tags/machine-next-pull-request:
  hw/intc/nvic: Use object_initialize_child for correct reference counting
  hw/arm/mps2: Use object_initialize_child for correct reference counting
  hw/microblaze/zynqmp: Use object_initialize_child for correct ref. counting
  hw/microblaze/zynqmp: Use object_initialize_child for correct ref. counting
  hw/microblaze/zynqmp: Let the SoC manage the IPI devices
  hw/microblaze/zynqmp: Move the IPI state into the PMUSoC state
  hw/mips: Use object_initialize_child for correct reference counting
  hw/mips: Use object_initialize() on MIPSCPSState
  hw/arm: Use object_initialize_child for correct reference counting
  hw/arm/aspeed: Use object_initialize_child for correct ref. counting
  hw/arm/bcm2835: Use object_initialize_child for correct ref. counting
  hw/arm/bcm2835: Use object_initialize() on PL011State
  hw/arm/bcm2835: Use TYPE_PL011 instead of hardcoded string
  hw/virtio: Use object_initialize_child for correct reference counting
  hw/misc/macio: Use object_initialize_child for correct ref. counting
  hw/ppc/pnv: Use object_initialize_child for correct reference counting
  qom/object: Display more helpful message when an object type is missing

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

This attempts to clean-up the output to better match the output of the
rest of the QEMU check system when called with -makecheck. This includes:

  - formatting as "  TEST    iotest-FMT: nnn"
  - only dumping config on failure (when -makecheck enabled)

The non-make check output has been cleaned up as well:

  - line re-displayed (\r) at the end
  - fancy colours for pass/fail/skip
  - timestamps always printed (option removed)

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190503143904.31211-1-alex.bennee@linaro.org>
Tested-by: Thomas Huth <thuth@redhat.com>

Currently, all tests are in the "auto" group. This is a little bit pointless.
OTOH, we need a group for the tests that we can automatically run during
"make check" each time, too. Tests in this new group are supposed to run
with every possible QEMU configuration, for example they must run with every
QEMU binary (also non-x86), without failing when an optional features is
missing (but reporting "skip" is ok), and be able to run on all kind of host
filesystems and users (i.e. also as "nobody" or "root").
So let's use the "auto" group for this class of tests now. The initial
list has been determined by running the iotests with non-x86 QEMU targets
and with our CI pipelines on Gitlab, Cirrus-CI and Travis (i.e. including
macOS and FreeBSD).

Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20190502084506.8009-7-thuth@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Add support for generating a single targets coverage report. Execute:

  make coverage-report

In the target build directory. This coverage report only cares about
target specific blobs so only searches the target build subdirectory.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Commit 337f2311 actually claimed to do this in the commit log but
didn't actually. Oops.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

This provides the bootstrap and low level helper functions for an
alpha kernel.  We use direct access to the DP264 serial port for
test output, and hard machine halt to exit the emulation.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20190501184306.15208-1-richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

Expand the memory test to cover move of the softmmu code. Specifically
we:

  - improve commentary
  - add some helpers (for later BE support)
  - reduce boiler plate into helpers
  - add signed reads at various sizes/offsets
  - required -DCHECK_UNALIGNED

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

There is nothing inherently architecture specific about the memory
test although we may have to manage different restrictions of
unaligned access across architectures.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

This provides the bootstrap and low level helper functions for an
aarch64 kernel. We use semihosting to handle test output and exiting
the emulation. semihosting's parameter passing is a little funky so we
end up using the stack and pointing to that as the parameter block.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

We are starting to add assembler foe tests/tcg so lets make sure we
get the mode right.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

This is not really i386 only, we can have the same test for all
architectures supporting system tests.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

We can certainly support some common tests for system emulation that
make use of our minimal defined boot.S support. It will still be up to
individual architectures to ensure they build so we provide a
MULTIARCH_TESTS variable that they can tack onto TESTS themselves.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>

Install optional dependencies of QEMU to get better coverage.

The following components are now enabled:

  $ ./configure
  ...
  Multipath support yes
  VNC SASL support  yes
  RDMA support      yes
  PVRDMA support    yes
  libiscsi support  yes
  seccomp support   yes
  libpmem support   yes
  libudev           yes

Note: The udev-devel package is provided by systemd-devel.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190504055440.20406-1-philmd@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Marcel <Apfelbaum&lt;marcel.apfelbaum@gmail.com>

Based on the ubuntu.docker file.
Used to reproduce the build failure Peter was seeing.
Others might find this useful too ;)

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-Id: <20190503070241.24786-1-kraxel@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Seeing as I touched it I should at least keep an eye on it.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>