qemu-sparc update

# gpg: Signature made Sat 16 Jan 2016 12:32:06 GMT using RSA key ID AE0F321F
# gpg: Good signature from "Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>"

* remotes/mcayland/tags/qemu-sparc-signed:
  target-sparc: Migrate CWP and PIL for SPARC64
  target-sparc: Use VMState arrays for SPARC64 TLB/MMU state
  target-sparc: Convert to VMStateDescription
  target-sparc: Don't flush TLB in cpu_load function
  target-sparc: Split cpu_put_psr into side-effect and no-side-effect parts
  vmstate: define vmstate_info_uinttl
  vmstate: Introduce VMSTATE_VARRAY_MULTPLY
  vmstate: introduce CPU_DoubleU arrays
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In SPARC32 the env->cwp and env->psrpil state is part of the PSR
register, and gets migrated as part of that register.
In SPARC64 this state is in separate CWP and PIL registers, but we
were not doing anything to migrate those.

Add the missing fields to the migration vmstate (which is a
migration break, but without these fields migration is completely
broken anyway).

This change means that trying a save/load of a SPARC64 target at
the boot rom prompt now produces a system which at least responds
to keyboard input after the restore.
Reported-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

Use VMState arrays for SPARC64 TLB/MMU state. This is
a migration-break for SPARC64 (but not for SPARC32),
which is acceptable because currently migration does not
work for any SPARC64 machines due to the lack of any migration
of interrupt controller state.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

Convert the SPARC CPU from cpu_load/save functions to VMStateDescription.
We preserve migration compatibility with the previous version
(required for SPARC32 but not necessarily for SPARC64).
Signed-off-by: NJuan Quintela <quintela@redhat.com>
[PMM:
 * Rebase and update to apply to master
 * VMSTATE_STRUCT_POINTER now takes type, not pointer-to-type
 * QEMUTimer* are migrated via VMSTATE_TIMER_PTR
 * Put CPUTimer vmstate struct inside TARGET_SPARC64 ifdef
 * Convert handling of PSR to use a vmstate_psr, like Alpha and ARM
]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

There's no need to flush the TLB in the SPARC cpu_load function: we're
guaranteed to be loading state into a fresh clean configuration.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

For inbound migration we really want to be able to set the PSR without
having any side effects, but cpu_put_psr() calls cpu_check_irqs() which
might try to deliver CPU interrupts. Split cpu_put_psr() into the
no-side-effect and side-effect parts.

This includes reordering the cpu_check_irqs() to the end of cpu_put_psr(),
because that function may actually end up calling cpu_interrupt(), which
does not seem like a good thing to happen in the middle of updating the PSR.
Suggested-by: NBlue Swirl <blauwirbel@gmail.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

We are going to define arrays of this type, so we need the integer type.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
[PMM: updated to apply on current QEMU; renamed to 'uinttl'
 rather than 'uinttls' to match other vmstate naming]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

This allows to send a partial array where the size is another
structure field multiplied by a constant.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
[PMM: updated to current master]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

Add vmstate support for migrating arrays of CPU_DoubleU via
VMSTATE_CPUDOUBLE_ARRAY.
Signed-off-by: NJuan Quintela <quintela@redhat.com>
[PMM: rebased, since files have all moved since 2012;
 added VMSTATE_CPUDOUBLE_ARRAY_V for consistency with FLOAT64]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>

* qemu-char logfile facility
* NBD coroutine based negotiation
* bugfixes

# gpg: Signature made Fri 15 Jan 2016 17:58:28 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream:
  qemu-char: do not leak QemuMutex when freeing a character device
  qemu-char: add logfile facility to all chardev backends
  nbd-server: do not exit on failed memory allocation
  nbd-server: do not check request length except for reads and writes
  nbd-server: Coroutine based negotiation
  nbd: Split nbd.c
  nbd: Always call "close_fn" in nbd_client_new
  SCSI device: fix to incomplete QOMify
  iscsi: send readcapacity10 when readcapacity16 failed
  qemu-char: delete send_all/recv_all helper methods
  vmw_pvscsi: x-disable-pcie, x-old-pci-configuration back-compat props are 2.5 specific
  scsi: initialise info object with appropriate size
  i386: avoid null pointer dereference
  target-i386: do not duplicate page protection checks
  scsi: revert change to scsi_req_cancel_async and add assertions
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The leak is only apparent on Win32.  On POSIX platforms destroying a
mutex is not necessary.
Reported-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NDaniel P. Berrange <berrange@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Typically a UNIX guest OS will log boot messages to a serial
port in addition to any graphical console. An admin user
may also wish to use the serial port for an interactive
console. A virtualization management system may wish to
collect system boot messages by logging the serial port,
but also wish to allow admins interactive access.

Currently providing such a feature forces the mgmt app
to either provide 2 separate serial ports, one for
logging boot messages and one for interactive console
login, or to proxy all output via a separate service
that can multiplex the two needs onto one serial port.
While both are valid approaches, they each have their
own downsides. The former causes confusion and extra
setup work for VM admins creating disk images. The latter
places an extra burden to re-implement much of the QEMU
chardev backends logic in libvirt or even higher level
mgmt apps and adds extra hops in the data transfer path.

A simpler approach that is satisfactory for many use
cases is to allow the QEMU chardev backends to have a
"logfile" property associated with them.

 $QEMU -chardev socket,host=localhost,port=9000,\
                server=on,nowait,id-charserial0,\
		logfile=/var/log/libvirt/qemu/test-serial0.log
       -device isa-serial,chardev=charserial0,id=serial0

This patch introduces a 'ChardevCommon' struct which
is setup as a base for all the ChardevBackend types.
Ideally this would be registered directly as a base
against ChardevBackend, rather than each type, but
the QAPI generator doesn't allow that since the
ChardevBackend is a non-discriminated union. The
ChardevCommon struct provides the optional 'logfile'
parameter, as well as 'logappend' which controls
whether QEMU truncates or appends (default truncate).
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1452516281-27519-1-git-send-email-berrange@redhat.com>
[Call qemu_chr_parse_common if cd->parse is NULL. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The amount of memory allocated in nbd_co_receive_request is driven by the
NBD client (possibly a virtual machine).  Parallel I/O can cause the
server to allocate a large amount of memory; check for failures and
return ENOMEM in that case.

Cc: qemu-block@nongnu.org
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Only reads and writes need to allocate memory correspondent to the
request length.  Other requests can be sent to the storage without
allocating any memory, and thus any request length is acceptable.
Reported-by: NSitsofe Wheeler <sitsofe@yahoo.com>
Cc: qemu-block@nongnu.org
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Create a coroutine in nbd_client_new, so that nbd_send_negotiate doesn't
need qemu_set_block().

Handlers need to be set temporarily for csock fd in case the coroutine
yields during I/O.

With this, if the other end disappears in the middle of the negotiation,
we don't block the whole event loop.

To make the code clearer, unify all function names that belong to
negotiate, so they are less likely to be misused. This is important
because we rely on negotiation staying in main loop, as commented in
nbd_negotiate_read/write().
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-4-git-send-email-famz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We have NBD server code and client code, all mixed in a file. Now split
them into separate files under nbd/, and update MAINTAINERS.

filter_nbd for iotest 083 is updated to keep the log filtered out.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-3-git-send-email-famz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Rename the parameter "close" to "close_fn" to disambiguous with
close(2).

This unifies error handling paths of NBDClient allocation:
nbd_client_new will shutdown the socket and call the "close_fn" callback
if negotiation failed, so the caller don't need a different path than
the normal close.

The returned pointer is never used, make it void in preparation for the
next patch.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <1452760863-25350-2-git-send-email-famz@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NCao jin <caoj.fnst@cn.fujitsu.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Message-Id: <1452073066-28319-1-git-send-email-caoj.fnst@cn.fujitsu.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

When play with Dell MD3000 target, for sure it
is a TYPE_DISK, but readcapacity16 would fail.
Then we find that readcapacity10 succeeded. It
looks like the target just support readcapacity10
even through it is a TYPE_DISK or have some
TYPE_ROM characteristics.

This patch can give a chance to send
readcapacity16 when readcapacity10 failed.
This patch is not harmful to original pathes
Signed-off-by: NZhu Lingshan <lszhu@suse.com>
Message-Id: <1451359934-9236-1-git-send-email-lszhu@suse.com>
[Don't fall through on UNIT ATTENTION. - Paolo]
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The qemu-char.c contains two helper methods send_all
and recv_all. These are in fact declared in sockets.h
so ought to have been in util/qemu-sockets.c. For added
fun the impl of recv_all is completely missing on Win32.

Fortunately there is only a single caller of these
methods, the TPM passthrough code, which is only
ever compiled on Linux. With only a single caller
these helpers are not compelling enough to keep so
inline them in the TPM code, avoiding the need to
fix the missing recv_all on Win32.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1450879144-17111-1-git-send-email-berrange@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

pvscsi's x-disable-pcie and x-old-pci-configuration backward compat
properties were introduced in 952970ba and d5da3ef2:

  vmw_pvscsi: Introduce 'x-old-pci-configuration' backword compatability property
  vmw_pvscsi: Introduce 'x-disable-pcie' backword compatability property

and were placed into HW_COMPAT_2_4.

However since these commits were pulled post v2.5, move them to
HW_COMPAT_2_5.
Signed-off-by: NShmulik Ladkani <shmulik.ladkani@ravellosystems.com>
Message-Id: <1450900558-20113-1-git-send-email-shmulik.ladkani@ravellosystems.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

While processing controller 'CTRL_GET_INFO' command, the routine
'megasas_ctrl_get_info' overflows the '&info' object size. Use its
appropriate size to null initialise it.
Reported-by: NQinghao Tang <luodalongde@gmail.com>
Signed-off-by: NPrasad J Pandit <pjp@fedoraproject.org>
Message-Id: <alpine.LFD.2.20.1512211501420.22471@wniryva>
Cc: qemu-stable@nongnu.org
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NP J P <ppandit@redhat.com>

    Hello,

A null pointer dereference issue was reported by Mr Ling Liu, CC'd here. It
occurs while doing I/O port write operations via hmp interface. In that,
'current_cpu' remains null as it is not called from cpu_exec loop, which
results in the said issue.

Below is a proposed (tested)patch to fix this issue; Does it look okay?

===
From ae88a4947fab9a148cd794f8ad2d812e7f5a1d0f Mon Sep 17 00:00:00 2001
From: Prasad J Pandit <pjp@fedoraproject.org>
Date: Fri, 18 Dec 2015 11:16:07 +0530
Subject: [PATCH] i386: avoid null pointer dereference

When I/O port write operation is called from hmp interface,
'current_cpu' remains null, as it is not called from cpu_exec()
loop. This leads to a null pointer dereference in vapic_write
routine. Add check to avoid it.
Reported-by: NLing Liu <liuling-it@360.cn>
Signed-off-by: NPrasad J Pandit <pjp@fedoraproject.org>
Message-Id: <alpine.LFD.2.20.1512181129320.9805@wniryva>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NP J P <ppandit@redhat.com>

x86_cpu_handle_mmu_fault is currently checking twice for writability
and executability of pages; the first time to decide whether to
trigger a page fault, the second time to compute the "prot" argument
to tlb_set_page_with_attrs.

Reorganize code so that first "prot" is computed, then it is used
to check whether to raise a page fault, then finally PROT_WRITE is
removed if the D bit will have to be set.
Reviewed-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Fam Zheng noticed that the change in commit 36896bff ("scsi: always call
notifier on async cancellation", 2015-12-16) could cause a leak of
the request; scsi_req_cancel_async now calls scsi_req_ref
multiple times for multiple cancellations, but there is only
one call to scsi_req_cancel_complete.

So revert the patch and instead assert that the problematic case (a call
to scsi_req_cancel_async after the aiocb has been completed) cannot
happen.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

target-arm queue:
 * use the right MMU index when handling unaligned accesses
 * xlnx-zynqmp: Add support for high DDR memory regions
 * target-arm: support QMP dump-guest-memory
 * ARM: virt: Don't generate RTC ACPI device when using UEFI

# gpg: Signature made Fri 15 Jan 2016 15:16:19 GMT using RSA key ID 14360CDE
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>"
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>"
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>"

* remotes/pmaydell/tags/pull-target-arm-20160115:
  ARM: virt: Don't generate RTC ACPI device when using UEFI
  target-arm: dump-guest-memory: add vfp notes for arm
  elf: add arm note types
  target-arm: dump-guest-memory: add prfpreg notes for aarch64
  target-arm: support QMP dump-guest-memory
  dump: allow target to set the physical base
  dump: allow target to set the page size
  dump: qemunotes aren't commonly needed
  qapi-schema: dump-guest-memory: Improve text
  xlnx-zynqmp: Add support for high DDR memory regions
  target-arm: Use the right MMU index in arm_regime_using_lpae_format
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

When booting the VM with UEFI, UEFI takes ownership of the RTC hardware.
While UEFI can use libfdt to disable the RTC device node in the DTB that
it passes to the OS, it cannot modify AML. Therefore, we won't generate
the RTC ACPI device at all when using UEFI.
Signed-off-by: NShannon Zhao <shannon.zhao@linaro.org>
Acked-by: NArd Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: NLaszlo Ersek <lersek@redhat.com>
Reviewed-by: NAndrew Jones <drjones@redhat.com>
Message-id: 1452867091-4023-1-git-send-email-shannon.zhao@linaro.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

gdb won't actually dump these with 'info all-registers' since
it first tries to confirm that it should by checking the VFP
hwcap in the .auxv note. Well, we don't generate an .auxv note.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-9-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-8-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-7-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Add the support needed for creating prstatus elf notes. This
allows us to use QMP dump-guest-memory.
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Message-id: 1452542185-10914-6-git-send-email-drjones@redhat.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
[PMM: moved setting of cpu::write_elf64_note inside !CONFIG_USER_ONLY
 ifdef to avoid compile failure for linux-user build]
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

crash assumes the physical base in the kdump subheader of
makedumpfile formatted dumps is correct. Zero is not correct
for all architectures, so allow it to be changed.

(No functional change.)
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-5-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This is necessary for targets that don't have TARGET_PAGE_SIZE ==
real-target-page-size. The target should set the page size to the
correct one, if known, or, if not known, to the maximum page size
it supports.

(No functional change.)
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-4-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Only one of three architectures implementing qmp-dump-guest-memory write
qemu notes. And, another architecture (arm/aarch64) is coming, which
won't use them either. Make the common implementation truly common.

(No functional change.)
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1452542185-10914-3-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

dump-guest-memory is supported by more than just x86, however
the paging option is not.

(No functional change.)
Signed-off-by: NAndrew Jones <drjones@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1452542185-10914-2-git-send-email-drjones@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The Xilinx ZynqMP SoC and EP108 board supports three memory regions:
 - A 2GB region starting at 0
 - A 32GB region starting at 32GB
 - A 256GB region starting at 768GB

This patch adds support for the first two memory regions, which is
automatically created based on the size specified by the QEMU memory
command line argument.

On hardware the physical memory region is one continuous region, it is then
mapped into the three different regions by the DDRC. As we don't model the
DDRC this is done at startup by QEMU. The board creates the memory region and
then passes that memory region to the SoC. The SoC then maps the memory
regions.
Signed-off-by: NAlistair Francis <alistair.francis@xilinx.com>
Reviewed-by: NPeter Crosthwaite <crosthwaite.peter@gmail.com>
Message-id: a1e47db941d65733724a300fcd98b74fbeeaaf22.1452637205.git.alistair.francis@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

arm_regime_using_lpae_format checks whether the LPAE extension is used
for stage 1 translation regimes. MMU indexes not exclusively of a stage 1
regime won't work with this method.

In case of ARMMMUIdx_S12NSE0 or ARMMMUIdx_S12NSE1, offset these values
by ARMMMUIdx_S1NSE0 to get the right index indicating a stage 1
translation regime.

Rename also the function to arm_s1_regime_using_lpae_format and update
the comments to reflect the change.
Signed-off-by: NAlvise Rigo <a.rigo@virtualopensystems.com>
Message-id: 1452854262-19550-1-git-send-email-a.rigo@virtualopensystems.com
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Commit 8acc216b attempted to silence some sign-compare
warnings in libvixl by adding -Wno-sign-compare to the CFLAGS
for the relevant objects. Unfortunately it was ineffective
because it was placed before $(QEMU_CFLAGS), so the -Wall in
the general flags overrode -Wno-sign-compare rather than
vice-versa. Reorder the flags so the warning suppression works.

Thanks to Franz-Josef Haider <Franz-Josef.Haider@student.uibk.ac.at>
for pointing out what was wrong with the original patch.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Tested-by: NAlex Bennée <alex.bennee@linaro.org>
Message-id: 1452783202-576-1-git-send-email-peter.maydell@linaro.org

Error reporting patches for 2016-01-13

# gpg: Signature made Wed 13 Jan 2016 14:21:48 GMT using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-error-2016-01-13: (41 commits)
  checkpatch: Detect newlines in error_report and other error functions
  error: Consistently name Error * objects err, and not errp
  s390/sclp: Simplify control flow in sclp_realize()
  hw/s390x: Rename local variables Error *l_err to just err
  error: Clean up errors with embedded newlines (again)
  vhdx: Fix "log that needs to be replayed" error message
  pci-assign: Clean up "Failed to assign" error messages
  vmdk: Clean up "Invalid extent lines" error message
  vmdk: Clean up control flow in vmdk_parse_extents() a bit
  error: Strip trailing '\n' from error string arguments (again)
  qemu-io qemu-nbd: Use error_report() etc. instead of fprintf()
  migration: Use error_reportf_err() instead of monitor_printf()
  spapr: Use error_reportf_err()
  error: Use error_prepend() where it makes obvious sense
  error: Use error_reportf_err() where it makes obvious sense
  error: Don't decorate original error message when adding to it
  error: New error_prepend(), error_reportf_err()
  test-throttle: Simplify qemu_init_main_loop() error handling
  qemu-nbd: Clean up "Failed to load snapshot" error message
  block: Clean up "Could not create temporary overlay" error message
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This first round of s390x patches includes:
- new compat machine
- remove the old s390-virtio machine
- fixes and some cleanup

# gpg: Signature made Wed 13 Jan 2016 14:55:55 GMT using RSA key ID C6F02FAF
# gpg: Good signature from "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"

* remotes/cohuck/tags/s390x-20160113:
  s390x/pci: return real state during listing PCI
  virtio-ccw: fix sanity check for vector
  s390: Introduce CCW_COMPAT_2_5
  s390x/virtio: use qemu_check_nic_model()
  s390x/pci: code cleanup
  s390x/pci: reject some operations to disabled PCI function
  s390x: remove s390-virtio devices
  s390x: remove s390-virtio machine
  s390x: add 2.6 compat machine
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>