Add a test for checking a qcow2 file with a multiple of 2^32 clusters.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This will let us print options in a format that the user would actually
write it on the command line (foo=bar,baz=asd,etc=def), without
prepending a spurious comma at the beginning of the list, or quoting
values unnecessarily. This patch provides the following changes:
* write and id=, if the option has an id
* do not print separator before the first element
* do not quote string arguments
* properly escape commas (,) for QEMU
Signed-off-by: Kővágó, Zoltán <DirtY.iCE.hu@gmail.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Currently, if a subprocess of a python test (i.e. qemu-io, qemu-img, or
qemu) receives a signal and is subsequently aborted, this is not logged.
This patch makes python tests always check the exit code of these
subprocesses, and emit a message if they have been killed.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently, if a qemu/qemu-io/qemu-img/qemu-nbd invocation receives a
segmentation fault, that message is invisible in most cases since the
output is generally filtered and bash suppresses the segmentation fault
notice for any but the last element of a pipe.
Most of the time, the test will then fail anyway because of missing
output, but not necessarily (as happened with test 82 recently).
Fix this by making the corresponding environment variables point to
wrapper functions which execute the respective command in a subshell.
Giving options to qemu/qemu-io/qemu-img and path names with spaces were
broken for the Python tests; this patch "accidentally" fixes that.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
While -nodefaults is set in $QEMU_OPTIONS, this is currently (wrongly)
ignored for Python iotests. In order to be prepared for when this is
fixed, we should explicitly add an IDE CD-ROM drive instead of relying
on it being created automatically.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch allows specifying the interface to be used for the drive, and
makes specifying a path optional (if the path is None, the "file" option
will be omitted, thus creating an empty drive).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The default device id of hard disk on the s390 platform is "virtio0"
which differs to the "ide0-hd0" for the x86 platform. Setting id in
the drive definition, ie:"qemu -drive id=testdisk", will be the same
on all platforms.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Bo Tu <tubo@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
when creating an image qemu-img enable us specifying the size of the
image using -o size=xx options. But when we specify an invalid size
such as a negtive size then different platform gives different result.
parse_option_size() function in util/qemu-option.c will be called to
parse the size, a cast was called in the function to cast the input
(saved as a double in the function) size to an unsigned int64 value,
when the input is a negtive value or exceeds the maximum of uint64, then
the result is undefined.
According to C99 6.3.1.4, the result of converting a floating point
number to an integer that cannot represent the (integer part of) number
is undefined. And sure enough the results are different on x86 and
s390.
C99 Language spec 6.3.1.4 Real floating and integers:
the result of this assignment/cast is undefined if the float is not
in the open interval (-1, U<type>_MAX+1).
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Bo Tu <tubo@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There is no 'ide-cd' device defined on non-pc platform, so
test_medium_not_found() test should be skipped.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Xiao Guang Chen <chenxg@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch fixes an io test suite issue that was introduced with the
commit c88930a686 'qemu-char: Permit only
a single "stdio" character device'. The option supresses the creation of
default devices such as the floopy and cdrom. Output files for test case
067, 071, 081 and 087 need to be updated to accommodate this change.
Use virtio-blk instead of virtio-blk-pci as the device driver for test
case 067. For virtio-blk-pci is the same with virtio-blk as device
driver but other platform such as s390 may not recognize the virtio-blk-pci.
The default devices differ across machines. As the qemu output often
contains these devices (or events for them, like opening a CD tray on
reset), the reference output currently is rather machine-specific.
All existing qemu tests explicitly configure the devices they're working
with, so just pass -nodefaults to qemu by default to disable the default
devices. Update the reference outputs accordingly.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Xiao Guang Chen <chenxg@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch adds qemu machine type support to the io test suite.
Based on the qemu default machine type and alias of the default machine
type the reference output file can now vary from the default to a
machine specific output file if necessary. When using a machine specific
reference file if the default machine has an alias then use the alias as the output
file name otherwise use the default machine name as the output file name.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Michael Mueller <mimu@linux.vnet.ibm.com>
Reviewed-by: Sascha Silbe <silbe@linux.vnet.ibm.com>
Signed-off-by: Xiao Guang Chen <chenxg@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This checks that VPC is able to successfully fail (without segfault)
on an image file with a max_table_entries that exceeds 0x40000000.
This table entry is within the valid range for VPC (although too large
for this sample image).
Cc: qemu-stable@nongnu.org
Signed-off-by: Jeff Cody <jcody@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Only poll the specific type of event we are interested in, to avoid
stealing events that should be consumed by someone else.
Suggested-by: John Snow <jsnow@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This checks that the discard on mirror source that effectively zeroes
data is also reflected by the data of target.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
If we wish to make differential backups a feature that's easy to access,
it might be pertinent to rename the "dirty-bitmap" mode to "incremental"
to make it clear what /type/ of backup the dirty-bitmap is helping us
perform.
This is an API breaking change, but 2.4 has not yet gone live,
so we have this flexibility.
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1433463642-21840-2-git-send-email-jsnow@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Commit f006cf7fa9 ("qdev-monitor:
Propagate errors through qdev_device_add()") dropped a meaningless error
message. This change in output caused qemu-iotests 051 to fail:
QEMU_PROG: -device ide-drive,drive=disk: Device initialization failed.
-QEMU_PROG: -device ide-drive,drive=disk: Device 'ide-drive' could not be initialized
Update 051.out so the test passes again.
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 1435071369-30936-1-git-send-email-stefanha@redhat.com
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Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging
Block layer core and image format patches
# gpg: Signature made Fri Jun 12 16:08:53 2015 BST using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
* remotes/kevin/tags/for-upstream: (25 commits)
block: Fix reopen flag inheritance
block: Add BlockDriverState.inherits_from
block: Add list of children to BlockDriverState
queue.h: Add QLIST_FIX_HEAD_PTR()
block: Drain requests before swapping nodes in bdrv_swap()
block: Move flag inheritance to bdrv_open_inherit()
block: Use QemuOpts in bdrv_open_common()
block: Use macro for cache option names
vmdk: Use bdrv_open_image()
quorum: Use bdrv_open_image()
check-qdict: Test cases for new functions
qdict: Add qdict_{set,copy}_default()
qdict: Add qdict_array_entries()
iotests: Add tests for overriding BDRV_O_PROTOCOL
block: driver should override flags in bdrv_open()
block: Change bitmap truncate conditional to assertion
block: record new size in bdrv_dirty_bitmap_truncate
raw-posix: Fix .bdrv_co_get_block_status() for unaligned image size
vmdk: Use vmdk_find_index_in_cluster everywhere
vmdk: Fix index_in_cluster calculation in vmdk_co_get_block_status
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This adds tests for overriding the qemu-internal BDRV_O_PROTOCOL flag by
explicitly specifying a block driver. As one test must be run over the
NBD protocol while the other must not, this patch adds two separate
iotests.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The BDRV_O_PROTOCOL flag should have an impact only if no driver is
specified explicitly. Therefore, if bdrv_open() is called with an
explicit block driver argument (either through the options QDict or
through the drv parameter) and that block driver is a protocol block
driver, BDRV_O_PROTOCOL should be set; if it is a format block driver,
BDRV_O_PROTOCOL should be unset.
While there was code to unset the flag in case a format block driver
has been selected, it only followed the bdrv_fill_options() function
call whereas the flag in fact needs to be adjusted before it is used
there.
With that change, BDRV_O_PROTOCOL will always be set if the BDS should
be a protocol driver; if the driver has been specified explicitly, the
new code will set it; and bdrv_fill_options() will only "probe" a
protocol driver if BDRV_O_PROTOCOL is set. The probing after
bdrv_fill_options() cannot select a protocol driver.
Thus, bdrv_open_image() to open BDS.file is never called if a protocol
BDS is about to be created. With that change in turn it is impossible to
call bdrv_open_common() with a protocol drv and file != NULL, which
allows us to remove the bdrv_swap() call.
This change breaks a test case in qemu-iotest 051:
"-drive file=t.qcow2,file.driver=qcow2" now works because the explicitly
specified "qcow2" overrides the BDRV_O_PROTOCOL which is automatically
set for the "file" BDS (and the filename is just passed down).
Therefore, this patch removes that test case.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds a test case to test 103 for performing a COW operation in a
qcow2 image using an L2 cache with minimal size (which should be at
least two clusters so the COW can access both source and destination
simultaneously).
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
If passwordless "sudo" works, use it in the qemu-io cmd.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
RHEL6 doesn't have Python 2.7, so replace this call with
assertNotEqual(x, None) which will work just as well.
Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch improves the test by attaching a different number of drives
to the VM and putting them in the same throttling group. The test
verifies that the I/O is evenly distributed among all members of the
group, and that the limits are enforced.
By default the test is repeated 3 times with 1, 2 and 3 drives, but
the maximum number of simultaneous drives is configurable.
Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 513df1da5c658878191b579ebcddd985adcd4122.1433779731.git.berto@igalia.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Add a simple test case for qemu-iotests that covers read/write
with encrypted qcow2 files.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Adding "-d" option. The output goes to "tee" so it appears in your
console. Also, raise the verbosity of unnitest runner.
When testing a topic branch, it's possible that a bug introduced by a
code change makes the python test case hang, with debug output, it is
much easier to locate the problem.
This can also be helpful if you want to watch the progress of a python
test, it offers you a way to sense the speed of each test case method
you're writing.
Note: because there is no easy way to get *both* the verbose output and
the output expected by ./check comparison, the case would always fail
with an "output mismatch". The sole purpose of using this option is
giving developers a quick way to debug when things go wrong.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The image is contributed by Richard W.M. Jones.
Cc: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Test zero write in byte range 512~1024 for 4k alignment.
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 1431522721-3266-4-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-22-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-13-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Roman Kagan <rkagan@parallels.com>
Message-id: 1430207220-24458-11-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
suggested by Jeff Cody
Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Roman Kagan <rkagan@parallels.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1430207220-24458-2-git-send-email-den@openvz.org
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Test what happens if you fiddle with the granularity.
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-22-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Test the failure case for incremental backups.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-21-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-20-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
A filter is added to allow callers to request very specific
events to be pulled from the event queue, while leaving undesired
events still in the stream.
This allows us to poll for completion data for multiple asynchronous
events in any arbitrary order.
A new timeout context is added to the qmp pull_event method's
wait parameter to allow tests to fail if they do not complete
within some expected period of time.
Also fixed is a bug in qmp.pull_event where we try to retrieve an event
from an empty list if we attempt to retrieve an event with wait=False
but no events have occurred.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-19-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1429314609-29776-18-git-send-email-jsnow@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1428069921-2957-4-git-send-email-famz@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds a regression test for some problems that the qemu-img convert
rewrite just fixed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
In recent qemu versions, it is possible to override the backing file
name and format that is stored in the image file with values given at
runtime. In such cases, the temporary override could end up in the
image header if the qcow2 header was updated, while obviously correct
behaviour would be to leave the on-disk backing file path/format
unchanged.
Fix this and add a test case for it.
Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1428411796-2852-1-git-send-email-kwolf@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Error classes are a leftover from the days of "rich" error objects.
New code should always use ERROR_CLASS_GENERIC_ERROR. Commit
b7b9d39..7c6a4ab added uses of ERROR_CLASS_DEVICE_NOT_FOUND. Replace
them.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is easy to create only self-referential refblocks, but there are
cases where that is impossible. This adds a test for two of those cases
(combined in a single test case).
Suggested-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 1417798412-15330-1-git-send-email-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 1423598552-24301-3-git-send-email-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
We've steered users away from QCOW/QCOW2 encryption for a while,
because it's a flawed design (commit 136cd19 Describe flaws in
qcow/qcow2 encryption in the docs).
In addition to flawed crypto, we have comically bad usability, and
plain old bugs. Let me show you.
= Example images =
I'm going to use a raw image as backing file, and two QCOW2 images,
one encrypted, and one not:
$ qemu-img create -f raw backing.img 4m
Formatting 'backing.img', fmt=raw size=4194304
$ qemu-img create -f qcow2 -o encryption,backing_file=backing.img,backing_fmt=raw geheim.qcow2 4m
Formatting 'geheim.qcow2', fmt=qcow2 size=4194304 backing_file='backing.img' backing_fmt='raw' encryption=on cluster_size=65536 lazy_refcounts=off
$ qemu-img create -f qcow2 -o backing_file=backing.img,backing_fmt=raw normal.qcow2 4m
Formatting 'normal.qcow2', fmt=qcow2 size=4194304 backing_file='backing.img' backing_fmt='raw' encryption=off cluster_size=65536 lazy_refcounts=off
= Usability issues =
== Confusing startup ==
When no image is encrypted, and you don't give -S, QEMU starts the
guest immediately:
$ qemu-system-x86_64 -nodefaults -display none -monitor stdio normal.qcow2
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) info status
VM status: running
But as soon as there's an encrypted image in play, the guest is *not*
started, with no notification whatsoever:
$ qemu-system-x86_64 -nodefaults -display none -monitor stdio geheim.qcow2
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) info status
VM status: paused (prelaunch)
If the user figured out that he needs to type "cont" to enter his
keys, the confusion enters the next level: "cont" asks for at most
*one* key. If more are needed, it then silently does nothing. The
user has to type "cont" once per encrypted image:
$ qemu-system-x86_64 -nodefaults -display none -monitor stdio -drive if=none,file=geheim.qcow2 -drive if=none,file=geheim.qcow2
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) info status
VM status: paused (prelaunch)
(qemu) c
none0 (geheim.qcow2) is encrypted.
Password: ******
(qemu) info status
VM status: paused (prelaunch)
(qemu) c
none1 (geheim.qcow2) is encrypted.
Password: ******
(qemu) info status
VM status: running
== Incorrect passwords not caught ==
All existing encryption schemes give you the GIGO treatment: garbage
password in, garbage data out. Guests usually refuse to mount
garbage, but other usage is prone to data loss.
== Need to stop the guest to add an encrypted image ==
$ qemu-system-x86_64 -nodefaults -display none -monitor stdio
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) info status
VM status: running
(qemu) drive_add "" if=none,file=geheim.qcow2
Guest must be stopped for opening of encrypted image
(qemu) stop
(qemu) drive_add "" if=none,file=geheim.qcow2
OK
Commit c3adb58 added this restriction. Before, we could expose images
lacking an encryption key to guests, with potentially catastrophic
results. See also "Use without key is not always caught".
= Bugs =
== Use without key is not always caught ==
Encrypted images can be in an intermediate state "opened, but no key".
The weird startup behavior and the need to stop the guest are there to
ensure the guest isn't exposed to that state. But other things still
are!
* drive_backup
$ qemu-system-x86_64 -nodefaults -display none -monitor stdio geheim.qcow2
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) drive_backup -f ide0-hd0 out.img raw
Formatting 'out.img', fmt=raw size=4194304
I guess this writes encrypted data to raw image out.img. Good luck
with figuring out how to decrypt that again.
* commit
$ qemu-system-x86_64 -nodefaults -display none -monitor stdio geheim.qcow2
QEMU 2.2.50 monitor - type 'help' for more information
(qemu) commit ide0-hd0
I guess this writes encrypted data into the unencrypted raw backing
image, effectively destroying it.
== QMP device_add of usb-storage fails when it shouldn't ==
When the image is encrypted, device_add creates the device, defers
actually attaching it to when the key becomes available, then fails.
This is wrong. device_add must either create the device and succeed,
or do nothing and fail.
$ qemu-system-x86_64 -nodefaults -display none -usb -qmp stdio -drive if=none,id=foo,file=geheim.qcow2
{"QMP": {"version": {"qemu": {"micro": 50, "minor": 2, "major": 2}, "package": ""}, "capabilities": []}}
{ "execute": "qmp_capabilities" }
{"return": {}}
{ "execute": "device_add", "arguments": { "driver": "usb-storage", "id": "bar", "drive": "foo" } }
{"error": {"class": "DeviceEncrypted", "desc": "'foo' (geheim.qcow2) is encrypted"}}
{"execute":"device_del","arguments": { "id": "bar" } }
{"timestamp": {"seconds": 1426003440, "microseconds": 237181}, "event": "DEVICE_DELETED", "data": {"path": "/machine/peripheral/bar/bar.0/legacy[0]"}}
{"timestamp": {"seconds": 1426003440, "microseconds": 238231}, "event": "DEVICE_DELETED", "data": {"device": "bar", "path": "/machine/peripheral/bar"}}
{"return": {}}
This stuff is worse than useless, it's a trap for users.
If people become sufficiently interested in encrypted images to
contribute a cryptographically sane implementation for QCOW2 (or
whatever other format), then rewriting the necessary support around it
from scratch will likely be easier and yield better results than
fixing up the existing mess.
Let's deprecate the mess now, drop it after a grace period, and move
on.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit c4bacaf improved error reporting, but neglected to update
051.out. Commit 2726958 tried to redress, but didn't get it quite
right (punctuation difference), and shortly after commit
ae071cc..master improved error reporting some more, neglecting 051.out
some more. Sorry!
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
