qemu_aio_coroutine_enter() is (indirectly) called recursively when
processing co_queue_wakeup.  This can lead to stack exhaustion.

This patch rewrites co_queue_wakeup in an iterative fashion (instead of
recursive) with bounded memory usage to prevent stack exhaustion.

qemu_co_queue_run_restart() is inlined into qemu_aio_coroutine_enter()
and the qemu_coroutine_enter() call is turned into a loop to avoid
recursion.

There is one change that is worth mentioning:  Previously, when
coroutine A queued coroutine B, qemu_co_queue_run_restart() entered
coroutine B from coroutine A.  If A was terminating then it would still
stay alive until B yielded.  After this patch B is entered by A's parent
so that a A can be deleted immediately if it is terminating.

It is safe to make this change since B could never interact with A if it
was terminating anyway.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 20180322152834.12656-3-stefanha@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

QSIMPLEQ_CONCAT(a, b) joins a = a + b.  The new QSIMPLEQ_PREPEND(a, b)
API joins a = b + a.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 20180322152834.12656-2-stefanha@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Fix a decodetree problem with 16-bit insns

# gpg: Signature made Mon 26 Mar 2018 15:35:04 BST
# gpg:                using RSA key 64DF38E8AF7E215F
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>"
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-dt-20180326:
  scripts/decodetree: Fix insnmask not marked as global in main()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Block layer patches

# gpg: Signature made Mon 26 Mar 2018 15:33:01 BST
# gpg:                using RSA key 7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream:
  qemu-iotests: Test vhdx image creation with QMP
  vhdx: Check for 4 GB maximum log size on creation
  vhdx: Don't use error_setg_errno() with constant errno
  vhdx: Require power-of-two block size on create
  qemu-iotests: Test parallels image creation with QMP
  parallels: Check maximum cluster size on create
  qemu-iotests: Test invalid resize on luks
  luks: Turn another invalid assertion into check
  qemu-iotests: Enable 025 for luks
  qemu-iotests: Test vdi image creation with QMP
  vdi: Fix build with CONFIG_VDI_DEBUG
  vdi: Change 'static' create option to 'preallocation' in QMP
  qcow2: Reset free_cluster_index when allocating a new refcount block
  include/block/block_int: Document protocol related functions
  block/blkreplay: Remove protocol-related fields
  block/throttle: Remove protocol-related fields
  block/quorum: Remove protocol-related fields
  block/replication: Remove protocol_name field
  iotests: 163 is not quick
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

if '-w 16' was given as a cmdline args a local copy of insnmask
is set and not the global one.
Signed-off-by: NPeer Adelt <peer.adelt@hni.uni-paderborn.de>
Signed-off-by: NBastian Koppelmann <kbastian@mail.uni-paderborn.de>
Message-Id: <20180319115846.9662-1-kbastian@mail.uni-paderborn.de>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Miscellaenous bugfixes, including crash fixes from Alexey, Peter M. and
Thomas.

# gpg: Signature made Mon 26 Mar 2018 13:37:38 BST
# gpg:                using RSA key BFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  qemu-pr-helper: Actually allow users to specify pidfile
  chardev/char-fe: Allow NULL chardev in qemu_chr_fe_init()
  iothread: fix breakage on windows
  scsi: turn "is this a SCSI device?" into a conditional hint
  chardev-socket: remove useless if
  tcg: Really fix cpu_io_recompile
  vhost-user-test: add back memfd check
  vhost-user-test: do not hang if chardev creation failed
  scripts/device-crash-test: Remove fixed isapc-with-iommu entry
  hw/audio: Fix crashes when devices are used on ISA bus without DMA
  fdc: Exit if ISA controller does not support DMA
  hw/net/can: Fix segfaults when using the devices without bus
  WHPX improve vcpu_post_run perf
  WHPX fix WHvSetPartitionProperty in PropertyCode
  WHPX fix WHvGetCapability out WrittenSizeInBytes
  scripts/get_maintainer.pl: Print proper error message for missing $file
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Due to wrong specification of arguments to getopt_long() any
attempt to set pidfile resulted in:

1) the default to be leaked
2) the @pidfile variable to be set to NULL (because optarg is
NULL without this patch).
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>
Message-Id: <6f10cd53d361a395aa0e85a9311ec4e9a8fc11e5.1521868451.git.mprivozn@redhat.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

All the functions in char-fe.c handle the CharBackend
having a NULL Chardev pointer, which means that the
backend exists but is not connected to anything. The
exception is qemu_chr_fe_init(), which will crash if
passed a NULL Chardev pointer argument. This can happen
for various boards if they're started with 'nodefaults':
 arm-softmmu/qemu-system-arm -S -nodefaults -M cubieboard
 riscv32-softmmu/qemu-system-riscv32 -nodefaults -M sifive_e

Make qemu_chr_fe_init() accept a NULL chardev. This allows
UART models to handle NULL chardev properties without
generally needing to special case them or to manually
create a NullChardev.
Reported-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-Id: <20180323152948.27048-1-peter.maydell@linaro.org>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

OOB can enable iothread for parsing even on Windows.  We need some tunes
to enable that on Windows otherwise it'll break Windows users.  This
patch fixes the breakage on Windows with qemu-system-ppc.exe.
Reported-by: NHoward Spoelstra <hsp.cat7@gmail.com>
Tested-by: NHoward Spoelstra <hsp.cat7@gmail.com>
Suggested-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20180322085630.23654-1-peterx@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If the user does not have permissions to send ioctls to the device (due to
SELinux or cgroups, for example), the output can look like

qemu-kvm: -device scsi-block,drive=disk: cannot get SG_IO version number:
  Operation not permitted.  Is this a SCSI device?

but this is confusing because the ioctl was blocked _before_ the device
even received the SG_GET_VERSION_NUM ioctl.  Therefore, for EPERM errors
the suggestion should be eliminated.  To make that simpler, change the
code to use error_append_hint.
Reported-by: NAla Hino <ahino@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This trips Coverity, which believes the subsequent qio_channel_create_watch
can dereference a NULL pointer.  In reality, tcp_chr_connect's callers
all have s->ioc properly initialized, since they are all rooted at
tcp_chr_new_client.
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We have confused the number of instructions that have been
executed in the TB with the number of instructions needed
to repeat the I/O instruction.

We have used cpu_restore_state_from_tb, which means that
the guest pc is pointing to the I/O instruction.  The only
time the answer to the later question is not 1 is when
MIPS or SH4 need to re-execute the branch for the delay
slot as well.

We must rely on cpu->cflags_next_tb to generate the next TB,
as otherwise we have a race condition with other guest cpus
within the TB cache.

Fixes: 0790f868Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>
Message-Id: <20180319031545.29359-1-richard.henderson@linaro.org>
Tested-by: NPavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This revert commit fb68096d, and
modify test_read_guest_mem() to use different chardev names, when
using memfd (_test_server_free(), where the chardev is removed, runs
in idle).
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180215212552.26997-4-marcandre.lureau@redhat.com>
Acked-by: NMaxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Before the chardev name fix, the following error may happen: "attempt
to add duplicate property 'chr-test' to object (type 'container')",
due to races.

Sadly, error_vprintf() uses g_test_message(), so you have to use
read the cryptic --debug-log to see it. Later, it would make sense to
use g_critical() instead, and catch errors with
g_test_expect_message() (in glib 2.34).
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20180215212552.26997-5-marcandre.lureau@redhat.com>
Acked-by: NMaxime Coquelin <maxime.coquelin@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Fixed in a0c167a1 ("x86_iommu: check
if machine has PCI bus").
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1521193892-15552-5-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The cs4231a, gus and sb16 sound cards crash QEMU when the user tries
to instantiate them on a machine with DMA-less ISA bus (for example
with "qemu-system-mips64el -M mips -device sb16"). Add proper checks
to the realize functions to avoid the crashes.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1521193892-15552-4-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

A "powernv" machine type defines an ISA bus but it does not add any DMA
controller to it so it is possible to hit assert(fdctrl->dma) by
adding "-machine powernv -device isa-fdc".

This replaces assert() with an error message.
Signed-off-by: NAlexey Kardashevskiy <aik@ozlabs.ru>
[thuth: Slightly adjusted error message and updated scripts/device-crash-test]
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1521193892-15552-3-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The CAN devices can currently be used to crash QEMU, e.g.:

$ x86_64-softmmu/qemu-system-x86_64 -device kvaser_pci
Segmentation fault (core dumped)

So we've got to add a proper check here that the corresponding
bus is available.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Message-Id: <1521193892-15552-2-git-send-email-thuth@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This removes the additional call to WHvGetVirtualProcessorRegisters in
whpx_vcpu_post_run now that the WHV_VP_EXIT_CONTEXT is returned in all
WHV_RUN_VP_EXIT_CONTEXT structures.
Signed-off-by: NJustin Terry (VM) <juterry@microsoft.com>
Message-Id: <1521039163-138-4-git-send-email-juterry@microsoft.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This fixes a breaking change to WHvSetPartitionProperty to pass the 'in'
PropertyCode on function invocation introduced in Windows Insider SDK 17110.
Usage of this indicates the PropertyCode of the opaque PropertyBuffer passed in
on function invocation.

Also fixes the removal of the PropertyCode parameter from the
WHV_PARTITION_PROPERTY struct as it is now passed to the function directly.
Signed-off-by: NJustin Terry (VM) <juterry@microsoft.com>
Message-Id: <1521039163-138-3-git-send-email-juterry@microsoft.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This fixes a breaking change to WHvGetCapability to include the 'out'
WrittenSizeInBytes introduced in Windows Insider SDK 17110.

This specifies on return the safe length to read into the WHV_CAPABILITY
structure passed to the call.
Signed-off-by: NJustin Terry (VM) <juterry@microsoft.com>
Message-Id: <1521039163-138-2-git-send-email-juterry@microsoft.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

If you pass scripts/get_maintainer.pl the name of a FIFO or other
exciting object (/dev/stdin, for example), it would falsely print
"file not found".  Instead: stat the object rather than using -f so
that we do not mind if the object is not a file; and print the errno
value in the error message.
Signed-off-by: NIan Jackson <Ian.Jackson@eu.citrix.com>
CC: Thomas Huth <thuth@redhat.com>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Stefano Stabellini <sstabellini@kernel.org>
CC: Anthony PERARD <anthony.perard@citrix.com>
Message-Id: <1520535787-6223-13-git-send-email-ian.jackson@eu.citrix.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NIan Jackson <ian.jackson@eu.citrix.com>

Signed-off-by: NKevin Wolf <kwolf@redhat.com>

It's unclear what the real maximum is, but we use an uint32_t to store
the log size in vhdx_co_create(), so we should check that the given
value fits in 32 bits.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>

error_setg_errno() is meant for cases where we got an errno from the OS
that can add useful extra information to an error message. It's
pointless if we pass a constant errno, these cases should use plain
error_setg().
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>

Images with a non-power-of-two block size are invalid and cannot be
opened. Reject such block sizes when creating an image.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NJeff Cody <jcody@redhat.com>

Signed-off-by: NKevin Wolf <kwolf@redhat.com>

It's unclear what the real maximum cluster size is for the Parallels
format, but let's at least make sure that we don't get integer
overflows in our .bdrv_co_create implementation.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

This tests that the .bdrv_truncate implementation for luks doesn't crash
for invalid image sizes.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Commit e39e959e fixed an invalid assertion in the .bdrv_length
implementation, but left a similar assertion in place for
.bdrv_truncate. Instead of crashing when the user requests a too large
image size, fail gracefully.

A file size of exactly INT64_MAX caused failure before, but is actually
legal.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

We want to test resizing even for luks. The only change that is needed
is to explicitly zero out new space for luks because it's undefined.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NDaniel P. Berrangé <berrange@redhat.com>

Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Use qemu_uuid_unparse() instead of uuid_unparse() to make vdi.c compile
again when CONFIG_VDI_DEBUG is set. In order to prevent future bitrot,
replace '#ifdef CONFIG_VDI_DEBUG' by 'if (VDI_DEBUG)' so that the
compiler always sees the code.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

What static=on really does is what we call metadata preallocation for
other block drivers. While we can still change the QMP interface, make
it more consistent by using 'preallocation' for VDI, too.

This doesn't implement any new functionality, so the only supported
preallocation modes are 'off' and 'metadata' for now.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

When we try to allocate new clusters we first look for available ones
starting from s->free_cluster_index and once we find them we increase
their reference counts. Before we get to call update_refcount() to do
this last step s->free_cluster_index is already pointing to the next
cluster after the ones we are trying to allocate.

During update_refcount() it may happen however that we also need to
allocate a new refcount block in order to store the refcounts of these
new clusters (and to complicate things further that may also require
us to grow the refcount table). After all this we don't know if the
clusters that we originally tried to allocate are still available, so
we return -EAGAIN to ask the caller to restart the search for free
clusters.

This is what can happen in a common scenario:

  1) We want to allocate a new cluster and we see that cluster N is
     free.

  2) We try to increase N's refcount but all refcount blocks are full,
     so we allocate a new one at N+1 (where s->free_cluster_index was
     pointing at).

  3) Once we're done we return -EAGAIN to look again for a free
     cluster, but now s->free_cluster_index points at N+2, so that's
     the one we allocate. Cluster N remains unallocated and we have a
     hole in the qcow2 file.

This can be reproduced easily:

     qemu-img create -f qcow2 -o cluster_size=512 hd.qcow2 1M
     qemu-io -c 'write 0 124k' hd.qcow2

After this the image has 132608 bytes (256 clusters), and the refcount
block is full. If we write 512 more bytes it should allocate two new
clusters: the data cluster itself and a new refcount block.

     qemu-io -c 'write 124k 512' hd.qcow2

However the image has now three new clusters (259 in total), and the
first one of them is empty (and unallocated):

     dd if=hd.qcow2 bs=512c skip=256 count=1 | hexdump -C

If we write larger amounts of data in the last step instead of the 512
bytes used in this example we can create larger holes in the qcow2
file.

What this patch does is reset s->free_cluster_index to its previous
value when alloc_refcount_block() returns -EAGAIN. This way the caller
will try to allocate again the original clusters if they are still
free.

The output of iotest 026 also needs to be updated because now that
images have no holes some tests fail at a different point and the
number of leaked clusters is different.
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Clarify that:

- for protocols the brdv_file_open function is used instead
of bdrv_open;

- when protocol_name is set, a driver should expect
to be given only a filename and no other options.
Signed-off-by: NFabiano Rosas <farosas@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The blkreplay driver is not a protocol so it should implement bdrv_open
instead of bdrv_file_open and not provide a protocol_name.

Attempts to invoke this driver using protocol syntax
(i.e. blkreplay:<filename:options:...>) will now fail gracefully:

  $ qemu-img info blkreplay:foo
  qemu-img: Could not open 'blkreplay:foo': Unknown protocol 'blkreplay'
Signed-off-by: NFabiano Rosas <farosas@linux.vnet.ibm.com>
Reviewed-by: NPavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The throttle driver is not a protocol so it should implement bdrv_open
instead of bdrv_file_open and not provide a protocol_name.

Attempts to invoke this driver using protocol syntax
(i.e. throttle:<filename:options:...>) will now fail gracefully:

  $ qemu-img info throttle:foo
  qemu-img: Could not open 'throttle:foo': Unknown protocol 'throttle'
Signed-off-by: NFabiano Rosas <farosas@linux.vnet.ibm.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The quorum driver is not a protocol so it should implement bdrv_open
instead of bdrv_file_open and not provide a protocol_name.

Attempts to invoke this driver using protocol syntax
(i.e. quorum:<filename:options:...>) will now fail gracefully:

  $ qemu-img info quorum:foo
  qemu-img: Could not open 'quorum:foo': Unknown protocol 'quorum'
Signed-off-by: NFabiano Rosas <farosas@linux.vnet.ibm.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The protocol_name field is used when selecting a driver via protocol
syntax (i.e. <protocol_name>:<filename:options:...>). Drivers that are
only selected explicitly (e.g. driver=replication,mode=primary,...)
should not have a protocol_name.

This patch removes the protocol_name field from the brdv_replication
structure so that attempts to invoke this driver using protocol syntax
will fail gracefully:

  $ qemu-img info replication:foo
  qemu-img: Could not open 'replication:': Unknown protocol 'replication'

Buglink: https://bugs.launchpad.net/qemu/+bug/1726733Signed-off-by: NFabiano Rosas <farosas@linux.vnet.ibm.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>