It does not make much sense to use a backing image for the target when
you concatenate multiple images (because then there is no correspondence
between the source images' backing files and the target's); but it was
still possible to give one by using -o backing_file=X instead of -B X.

Fix this by moving the check.

(Also, change the error message because -B is not the only way to
 specify the backing file, evidently.)

Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
* applied patch from v1 of series as suggested by author
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

After storing the creation options for the new image into @opts, we
fetch some things for our own information, like the backing file name,
or whether to use encryption or preallocation.

With the -n parameter, there will not be any creation options; this is
not too bad because this just means that querying a NULL @opts will
always return the default value.

However, we also use @opts for the --object options. Therefore, @opts is
not necessarily NULL if -n was specified; instead, it may contain those
options. In practice, this probably does not cause any problems because
there most likely is no object that supports any of the parameters we
query here, but this is neither something we should rely on nor does
this variable reuse make the code very nice to read.

Therefore, just use an own variable for the --object options.

Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
* applied patch from v1 of series as suggested by author
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

Otherwise the qemu-img process will exit with EXIT_SUCCESS instead of
EXIT_FAILURE.

Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
* applied directly to stable, upstream code has issue fixed via a
  refactoring introduced by 9fd77f99, which isn't targetted for stable
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

We've been documenting the value in bytes since its introduction
in commit b9a9b3a4 (v1.3), where it was actually reported in bytes.

Commit e4654d2d (v2.0) then removed things from block/qapi.c, in
preparation for a rewrite to a list of dirty sectors in the next
commit 21b56835 in block.c, but the new code mistakenly started
reporting in sectors.

Fixes: https://bugzilla.redhat.com/1441460

CC: qemu-stable@nongnu.org
Signed-off-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
(cherry picked from commit 6c98c57a)
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

The QGA schema states:

@can-offline: Whether offlining the VCPU is possible. This member
               is always filled in by the guest agent when the structure
               is returned, and always ignored on input (hence it can be
               omitted then).

Currently 'can-offline' is missing entirely from the reply. This causes
errors in libvirt which is expecting the reply to be compliant with the
schema docs.

BZ#1438735: https://bugzilla.redhat.com/show_bug.cgi?id=1438735Signed-off-by: NSameeh Jubran <sameeh@daynix.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
(cherry picked from commit 54858553)
Signed-off-by: NMichael Roth <mdroth@linux.vnet.ibm.com>

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

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

# gpg: Signature made Tue 18 Apr 2017 15:58:32 BST
# gpg:                using RSA key 0xCA35624C6A9171C6
# gpg: Good signature from "Fam Zheng <famz@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 5003 7CB7 9706 0F76 F021  AD56 CA35 624C 6A91 71C6

* remotes/famz/tags/block-pull-request:
  block: Drain BH in bdrv_drained_begin
  block: Walk bs->children carefully in bdrv_drain_recurse
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

During block job completion, nothing is preventing
block_job_defer_to_main_loop_bh from being called in a nested
aio_poll(), which is a trouble, such as in this code path:

    qmp_block_commit
      commit_active_start
        bdrv_reopen
          bdrv_reopen_multiple
            bdrv_reopen_prepare
              bdrv_flush
                aio_poll
                  aio_bh_poll
                    aio_bh_call
                      block_job_defer_to_main_loop_bh
                        stream_complete
                          bdrv_reopen

block_job_defer_to_main_loop_bh is the last step of the stream job,
which should have been "paused" by the bdrv_drained_begin/end in
bdrv_reopen_multiple, but it is not done because it's in the form of a
main loop BH.

Similar to why block jobs should be paused between drained_begin and
drained_end, BHs they schedule must be excluded as well.  To achieve
this, this patch forces draining the BH in BDRV_POLL_WHILE.

As a side effect this fixes a hang in block_job_detach_aio_context
during system_reset when a block job is ready:

    #0  0x0000555555aa79f3 in bdrv_drain_recurse
    #1  0x0000555555aa825d in bdrv_drained_begin
    #2  0x0000555555aa8449 in bdrv_drain
    #3  0x0000555555a9c356 in blk_drain
    #4  0x0000555555aa3cfd in mirror_drain
    #5  0x0000555555a66e11 in block_job_detach_aio_context
    #6  0x0000555555a62f4d in bdrv_detach_aio_context
    #7  0x0000555555a63116 in bdrv_set_aio_context
    #8  0x0000555555a9d326 in blk_set_aio_context
    #9  0x00005555557e38da in virtio_blk_data_plane_stop
    #10 0x00005555559f9d5f in virtio_bus_stop_ioeventfd
    #11 0x00005555559fa49b in virtio_bus_stop_ioeventfd
    #12 0x00005555559f6a18 in virtio_pci_stop_ioeventfd
    #13 0x00005555559f6a18 in virtio_pci_reset
    #14 0x00005555559139a9 in qdev_reset_one
    #15 0x0000555555916738 in qbus_walk_children
    #16 0x0000555555913318 in qdev_walk_children
    #17 0x0000555555916738 in qbus_walk_children
    #18 0x00005555559168ca in qemu_devices_reset
    #19 0x000055555581fcbb in pc_machine_reset
    #20 0x00005555558a4d96 in qemu_system_reset
    #21 0x000055555577157a in main_loop_should_exit
    #22 0x000055555577157a in main_loop
    #23 0x000055555577157a in main

The rationale is that the loop in block_job_detach_aio_context cannot
make any progress in pausing/completing the job, because bs->in_flight
is 0, so bdrv_drain doesn't process the block_job_defer_to_main_loop
BH. With this patch, it does.
Reported-by: NJeff Cody <jcody@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <20170418143044.12187-3-famz@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>
Tested-by: NJeff Cody <jcody@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>

The recursive bdrv_drain_recurse may run a block job completion BH that
drops nodes. The coming changes will make that more likely and use-after-free
would happen without this patch

Stash the bs pointer and use bdrv_ref/bdrv_unref in addition to
QLIST_FOREACH_SAFE to prevent such a case from happening.

Since bdrv_unref accesses global state that is not protected by the AioContext
lock, we cannot use bdrv_ref/bdrv_unref unconditionally.  Fortunately the
protection is not needed in IOThread because only main loop can modify a graph
with the AioContext lock held.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-Id: <20170418143044.12187-2-famz@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>
Tested-by: NJeff Cody <jcody@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>

The local backend was recently converted to using "at*()" syscalls in order
to ensure all accesses happen below the shared directory. This requires that
we only pass relative paths, otherwise the dirfd argument to the "at*()"
syscalls is ignored and the path is treated as an absolute path in the host.
This is actually the case for paths in all fids, with the notable exception
of the root fid, whose path is "/". This causes the following backend ops to
act on the "/" directory of the host instead of the virtfs shared directory
when the export root is involved:
- lstat
- chmod
- chown
- utimensat

ie, chmod /9p_mount_point in the guest will be converted to chmod / in the
host for example. This could cause security issues with a privileged QEMU.

All "*at()" syscalls are being passed an open file descriptor. In the case
of the export root, this file descriptor points to the path in the host that
was passed to -fsdev.

The fix is thus as simple as changing the path of the export root fid to be
"." instead of "/".

This is CVE-2017-7471.

Cc: qemu-stable@nongnu.org
Reported-by: NLéo Gaspard <leo@gaspard.io>
Signed-off-by: NGreg Kurz <groug@kaod.org>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

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

In case of block migration, there may be writes to BlockBackends that do
not have the write permission taken. Before this issue is fixed (which
is not going to happen in 2.9), we therefore cannot assert that this is
the case.
Suggested-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Tested-by: NKevin Wolf <kwolf@redhat.com>
Message-id: 20170411145050.31290-1-mreitz@redhat.com
Tested-by: NLaurent Vivier <lvivier@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This fixes a regression introduced in commit 9d456654.

aio_co_wake() can only be used to reenter a coroutine that was already
previously entered, otherwise co->ctx is uninitialised and we access
garbage. Using it immediately after qemu_coroutine_create() like in
co_read_response() is wrong and causes segfaults.

Replace the call with aio_co_enter(), which gets an explicit AioContext
parameter and works even for new coroutines.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Tested-by: NKashyap Chamarthy <kchamart@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Message-id: 1491919733-21065-1-git-send-email-kwolf@redhat.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Block patches for 2.9.0-rc4

# gpg: Signature made Tue 11 Apr 2017 14:40:07 BST
# gpg:                using RSA key 0xF407DB0061D5CF40
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>"
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2017-04-11:
  iscsi: Fix iscsi_create
  throttle: Remove block from group on hot-unplug
  block: pass the right options for BlockDriver.bdrv_open()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Since d5895fcb (iscsi: Split URL into individual options), creating
qcow2 image on an iscsi LUN fails:

    qemu-img create -f qcow2 iscsi://$SERVER/$IQN/0 1G
    qemu-img: iscsi://$SERVER/$IQN/0: Could not create image: Invalid
        argument

The problem is iscsi_open now expects that transport_name, portal and
target are already parsed into structured options by
iscsi_parse_filename, but it is not called in iscsi_create.
Signed-off-by: NFam Zheng <famz@redhat.com>
Message-id: 20170410075451.21329-1-famz@redhat.com
Reviewed-by: NEric Blake <eblake@redhat.com>
[mreitz: Dropped now superfluous
         qdict_put(bs_options, "filename", ...)]
Signed-off-by: NMax Reitz <mreitz@redhat.com>

When a block device that is part of a throttle group is hot-unplugged,
we forgot to remove it from the throttle group. This leaves stale
memory around, and causes an easily reproducible crash:

$ ./x86_64-softmmu/qemu-system-x86_64 -nodefaults -nographic -qmp stdio \
-device virtio-scsi-pci,bus=pci.0 -drive \
id=drive_image2,if=none,format=raw,file=file2,bps=512000,iops=100,group=foo \
-device scsi-hd,id=image2,drive=drive_image2 -drive \
id=drive_image3,if=none,format=raw,file=file3,bps=512000,iops=100,group=foo \
-device scsi-hd,id=image3,drive=drive_image3
{'execute':'qmp_capabilities'}
{'execute':'device_del','arguments':{'id':'image3'}}
{'execute':'system_reset'}

Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1428810Suggested-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NEric Blake <eblake@redhat.com>
Message-id: 20170406190847.29347-1-eblake@redhat.com
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

raw_open() expects the caller always passing in the right actual
@options parameter. But when trying to applying snapshot on a RBD
image, bdrv_snapshot_goto() calls raw_open() (by calling the
bdrv_open callback on the BlockDriver) with a NULL @options, and
that will result in a Segmentation fault.

For the other non-raw format drivers, it also makes sense to passing
in the actual options, althought they don't trigger the problem so
far.

Let's prepare a @options by adding the "file" key-value pair to a
copy of the actual options that were given for the node (i.e.
bs->options), and pass it to the callback.

BlockDriver.bdrv_open() expects bs->file to be NULL and just
overwrites it with the result from bdrv_open_child(). That means we
should actually make sure it's NULL because otherwise the child BDS
will have a reference count that is 1 too high. So we unconditionally
invoke bdrv_unref_child() before calling BlockDriver.bdrv_open(), and
we wrap everything in bdrv_ref()/bdrv_unref() so the BDS isn't
deleted in the meantime.
Suggested-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-id: 20170405091909.36357-2-bjsdjshi@linux.vnet.ibm.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

# gpg: Signature made Tue 11 Apr 2017 13:10:55 BST
# gpg:                using RSA key 0xCA35624C6A9171C6
# gpg: Good signature from "Fam Zheng <famz@redhat.com>"
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 5003 7CB7 9706 0F76 F021  AD56 CA35 624C 6A91 71C6

* remotes/famz/tags/block-pull-request:
  sheepdog: Use bdrv_coroutine_enter before BDRV_POLL_WHILE
  block: Fix bdrv_co_flush early return
  block: Use bdrv_coroutine_enter to start I/O coroutines
  qemu-io-cmds: Use bdrv_coroutine_enter
  blockjob: Use bdrv_coroutine_enter to start coroutine
  block: Introduce bdrv_coroutine_enter
  async: Introduce aio_co_enter
  coroutine: Extract qemu_aio_coroutine_enter
  tests/block-job-txn: Don't start block job before adding to txn
  block: Quiesce old aio context during bdrv_set_aio_context
  block: Make bdrv_parent_drained_begin/end public
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

When called from main thread, the coroutine should run in the context of
bs. Use bdrv_coroutine_enter to ensure that.
Signed-off-by: NFam Zheng <famz@redhat.com>

bdrv_inc_in_flight and bdrv_dec_in_flight are mandatory for
BDRV_POLL_WHILE to work, even for the shortcut case where flush is
unnecessary. Move the if block to below bdrv_dec_in_flight, and BTW fix
the variable declaration position.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>

BDRV_POLL_WHILE waits for the started I/O by releasing bs's ctx then polling
the main context, which relies on the yielded coroutine continuing on bs->ctx
before notifying qemu_aio_context with bdrv_wakeup().

Thus, using qemu_coroutine_enter to start I/O is wrong because if the coroutine
is entered from main loop, co->ctx will be qemu_aio_context, as a result of the
"release, poll, acquire" loop of BDRV_POLL_WHILE, race conditions happen when
both main thread and the iothread access the same BDS:

  main loop                                iothread
-----------------------------------------------------------------------
  blockdev_snapshot
    aio_context_acquire(bs->ctx)
                                           virtio_scsi_data_plane_handle_cmd
    bdrv_drained_begin(bs->ctx)
    bdrv_flush(bs)
      bdrv_co_flush(bs)                      aio_context_acquire(bs->ctx).enter
        ...
        qemu_coroutine_yield(co)
      BDRV_POLL_WHILE()
        aio_context_release(bs->ctx)
                                             aio_context_acquire(bs->ctx).return
                                               ...
                                                 aio_co_wake(co)
        aio_poll(qemu_aio_context)               ...
          co_schedule_bh_cb()                    ...
            qemu_coroutine_enter(co)             ...

              /* (A) bdrv_co_flush(bs)           /* (B) I/O on bs */
                      continues... */
                                             aio_context_release(bs->ctx)
        aio_context_acquire(bs->ctx)

Note that in above case, bdrv_drained_begin() doesn't do the "release,
poll, acquire" in BDRV_POLL_WHILE, because bs->in_flight == 0.

Fix this by using bdrv_coroutine_enter and enter coroutine in the right
context.

iotests 109 output is updated because the coroutine reenter flow during
mirror job complete is different (now through co_queue_wakeup, instead
of the unconditional qemu_coroutine_switch before), making the end job
len different.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

qemu_coroutine_create associates @co to qemu_aio_context but we poll
blk's context below. If the coroutine yields, it may never get resumed
again.

Use bdrv_coroutine_enter to make sure we are starting the I/O on the
right context.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

Resuming and especially starting of the block job coroutine, could be issued in
the main thread.  However the coroutine's "home" ctx should be set to the same
context as job->blk. Use bdrv_coroutine_enter to ensure that.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

They start the coroutine on the specified context.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

It's a variant of qemu_coroutine_enter with an explicit AioContext
parameter.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

Previously, before test_block_job_start returns, the job can already
complete, as a result, the transactional state of other jobs added to
the same txn later cannot be handled correctly.

Move the block_job_start() calls to callers after
block_job_txn_add_job() calls.
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

The fact that the bs->aio_context is changing can confuse the dataplane
iothread, because of the now fine granularity aio context lock.
bdrv_drain should rather be a bdrv_drained_begin/end pair, but since
bs->aio_context is changing, we can just use aio_disable_external and
bdrv_parent_drained_begin.
Reported-by: NEd Swierk <eswierk@skyportsystems.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NFam Zheng <famz@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Acked-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

qxl: bugfixes.

# gpg: Signature made Tue 11 Apr 2017 08:00:00 BST
# gpg:                using RSA key 0x4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/pull-fixes-20170411-1:
  qxl: add migration blocker to avoid pre-save assert
  qxl: switch display on entering VGA
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Cc: 1635339@bugs.launchpad.net
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20170410113131.2585-1-kraxel@redhat.com

Fixes a memory leak.

# gpg: Signature made Mon 10 Apr 2017 13:20:39 BST
# gpg:                using DSA key 0x02FC3AEB0101DBC2
# gpg: Good signature from "Greg Kurz <groug@kaod.org>"
# gpg:                 aka "Greg Kurz <groug@free.fr>"
# gpg:                 aka "Greg Kurz <gkurz@linux.vnet.ibm.com>"
# gpg:                 aka "Gregory Kurz (Groug) <groug@free.fr>"
# gpg:                 aka "[jpeg image of size 3330]"
# 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: 2BD4 3B44 535E C0A7 9894  DBA2 02FC 3AEB 0101 DBC2

* remotes/gkurz/tags/for-upstream:
  9pfs: xattr: fix memory leak in v9fs_list_xattr
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Final icount and misc MTTCG fixes for 2.9

Minor differences from:
  Message-Id: <20170405132503.32125-1-alex.bennee@linaro.org>

  - dropped new feature patches
  - last minute typo fix from Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>

# gpg: Signature made Mon 10 Apr 2017 11:38:10 BST
# gpg:                using RSA key 0xFBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>"
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-mttcg-fixups-for-rc2-100417-1:
  replay: assert time only goes forward
  cpus: call cpu_update_icount on read
  cpu-exec: update icount after each TB_EXIT
  cpus: introduce cpu_update_icount helper
  cpus: don't credit executed instructions before they have run
  cpus: move icount preparation out of tcg_exec_cpu
  cpus: check cpu->running in cpu_get_icount_raw()
  cpus: remove icount handling from qemu_tcg_cpu_thread_fn
  target/i386/misc_helper: wrap BQL around another IRQ generator
  cpus: fix wrong define name
  scripts/qemugdb/mtree.py: fix up mtree dump
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

In the 2.7 release we stated in the ChangeLog that the
minimum glib version for Windows hosts was 2.30, but we
didn't update configure to enforce this because we were
very close to the release at the point where we noticed
the issue, and it only affected building the test suite.
We then forgot that we needed to do it. Fix the omission.

(The reason for the 2.30 requirement is use of
g_dir_make_tmp() -- our fallback implementation uses
mkdtemp(), which isn't available on Windows.)
Reported-by: NMark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NStefan Weil <sw@weilnetz.de>
Message-id: 1491224655-5776-1-git-send-email-peter.maydell@linaro.org

If we find ourselves trying to add an event to the log where time has
gone backwards it is because a vCPU event has occurred and the
main-loop is not yet aware of time moving forward. This should not
happen and if it does its better to fail early than generate a log
that will have weird behaviour.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

This ensures each time the vCPU thread reads the icount we update the
master timer_state.qemu_icount field. This way as long as updates are
in BQL protected sections (which they should be) the main-loop can
never come to update the log and find time has gone backwards.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

There is no particular reason we shouldn't update the global system
icount time as we exit each TranslationBlock run. This ensures the
main-loop doesn't have to wait until we exit to the outer loop for
executed instructions to be credited to timer_state.

The prepare_icount_for_run function is slightly tweaked to match the
logic we run in cpu_loop_exec_tb.

Based on Paolo's original suggestion.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

By holding off updates to timer_state.qemu_icount we can run into
trouble when the non-vCPU thread needs to know the time. This helper
ensures we atomically update timers_state.qemu_icount based on what
has been currently executed.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

Outside of the vCPU thread icount time will only be tracked against
timers_state.qemu_icount. We no longer credit cycles until they have
completed the run. Inside the vCPU thread we adjust for passage of
time by looking at how many have run so far. This is only valid inside
the vCPU thread while it is running.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>