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2014-04-29block: Add '--version' option to qemu-imgJeff Cody1-4/+11
This allows qemu-img to print out version information, without needing to print the long help wall of text. While there, perform some minor whitespace cleanup, and remove the unused option_index variable in the call to getopt_long(). Reported-by: Eric Blake <eblake@redhat.com> Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-04-28block: fix qemu-img --help invocationJeff Cody1-2/+13
This fixes a bug introduced in commit ac1307ab, that caused the '--help' option to not be recognized as a valid command, and not print any help. Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-04-25qemu-img: Consistently name Error * objects err, and not errpMarkus Armbruster1-6/+6
Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-04-22qemu-img: Improve error messagesFam Zheng1-28/+46
Previously, when there is a user error in argv parsing, qemu-img prints help text and exits. Add an error_exit function to print a helpful error message and a hint to run 'qemu-img --help' for more information. As a bonus, "qemu-img <cmd> --help" now has a more reasonable exit code 0. In the future the help text should be split by sub command, and only print the information for the specified command. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-04-22qemu-img: Avoid duplicate block device IDsKevin Wolf1-16/+22
qemu-img used to use "image" as ID for all block devices. This means that e.g. img_convert() ended up with potentially multiple source images and one target image, all with the same ID. The next patch will catch this and fail to open the block device. This patch makes sure that qemu-img uses meaningful unique IDs for the block devices it uses. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-04-22block: Add errp to bdrv_new()Kevin Wolf1-3/+3
This patch adds an errp parameter to bdrv_new() and updates all its callers. The next patches will make use of this in order to check for duplicate IDs. Most of the callers know that their ID is fine, so they can simply assert that there is no error. Behaviour doesn't change with this patch yet as bdrv_new() doesn't actually assign errors to errp. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-04-01qemu-img: Release reference to BlockDriverStatePrasad Joshi1-0/+1
Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-25qemu-img: mandate argument to 'qemu-img check --repair'Prasad Joshi1-1/+1
qemu-img check --repair option accepts an argument. The argument to --repair switch can either be 'all' or 'leak'. Fix the long option to mandate argument with --repair switch. The patch fixes following segmentation fault Core was generated by `qemu-img check -f qcow2 --repair all t.qcow2'. Program terminated with signal 11, Segmentation fault. 0 in img_check (argc=6, argv=0x7fffab9b8a10) at qemu-img.c:588 588 if (!strcmp(optarg, "leaks")) { (gdb) bt 0 img_check (argc=6, argv=0x7fffab9b8a10) at qemu-img.c:588 1 __libc_start_main () from /lib/x86_64-linux-gnu/libc.so.6 2 _start () (gdb) Signed-off-by: Prasad Joshi <prasadjoshi.linux@gmail.com> Reviewed-by: Leandro Dorileo <l@dorileo.org> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-03-05qemu-img convert: Fix progress outputKevin Wolf1-9/+11
Initialise progress output only when the -p and -q options have already been parsed, otherwise it's always disabled. Reported-by: Peter Lieven <pl@kamp.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-03-03qemu-img: Remove unneeded include filesStefan Weil1-6/+0
There is no dependency on windows.h, and the standard include files are already included by qemu-common.h. Signed-off-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-02-25Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into stagingPeter Maydell1-45/+100
Block patches # gpg: Signature made Fri 21 Feb 2014 21:42:24 GMT using RSA key ID C88F2FD6 # gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" * remotes/kevin/tags/for-upstream: (54 commits) iotests: Mixed quorum child device specifications quorum: Simplify quorum_open() quorum: Add unit test. quorum: Add quorum_open() and quorum_close(). quorum: Implement recursive .bdrv_recurse_is_first_non_filter in quorum. quorum: Add quorum_co_flush(). quorum: Add quorum_invalidate_cache(). quorum: Add quorum_getlength(). quorum: Add quorum mechanism. quorum: Add quorum_aio_readv. blkverify: Extract qemu_iovec_clone() and qemu_iovec_compare() from blkverify. quorum: Add quorum_aio_writev and its dependencies. quorum: Create BDRVQuorumState and BlkDriver and do init. quorum: Create quorum.c, add QuorumChildRequest and QuorumAIOCB. check-qdict: Test termination of qdict_array_split() check-qdict: Adjust test for qdict_array_split() qdict: Extract non-QDicts in qdict_array_split() qemu-config: Sections must consist of keys qemu-iotests: Check qemu-img command line parsing qemu-img: Allow -o help with incomplete argument list ... Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-24Merge remote-tracking branch 'remotes/bonzini/configure' into stagingPeter Maydell1-0/+1
* remotes/bonzini/configure: build: softmmu targets do not have a "main.o" file configure: Disable libtool if -fPIE does not work with it (bug #1257099) block: convert block drivers linked with libs to modules Makefile: introduce common-obj-m and block-obj-m for DSO Makefile: install modules with "make install" module: implement module loading rules.mak: introduce DSO rules darwin: do not use -mdynamic-no-pic block: use per-object cflags and libs rules.mak: allow per object cflags and libs rules.mak: fix $(obj) to a real relative path util: Split out exec_dir from os_find_datadir Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-02-21qemu-img: Allow -o help with incomplete argument listKevin Wolf1-23/+35
This patch allows using 'qemu-img $subcmd -o help' for the create, convert and amend subcommands, without specifying the previously required filename arguments. Note that it's still allowed and meaningful to specify a filename: An invocation like 'qemu-img create -o help sheepdog:foo' will also display options that are provided by the Sheepdog driver. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-02-21qemu-img amend: Support multiple -o optionsKevin Wolf1-2/+15
Instead of ignoring all option values but the last one, multiple -o options now have the same meaning as having a single option with all settings in the order of their respective -o options. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-02-21qemu-img convert: Support multiple -o optionsKevin Wolf1-9/+25
Instead of ignoring all option values but the last one, multiple -o options now have the same meaning as having a single option with all settings in the order of their respective -o options. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-02-21qemu-img create: Support multiple -o optionsKevin Wolf1-6/+22
If you specified multiple -o options for qemu-img create, it would silently ignore all but the last one. This patch fixes the problem. Now multiple -o options has the same meaning as having a single option with all settings in the order of their respective -o options. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2014-02-21block: Add reference parameter to bdrv_open()Max Reitz1-4/+4
Allow bdrv_open() to handle references to existing block devices just as bdrv_file_open() is already capable of. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-21block: Change BDS parameter of bdrv_open() to **Max Reitz1-6/+4
Make bdrv_open() take a pointer to a BDS pointer, similarly to bdrv_file_open(). If a pointer to a NULL pointer is given, bdrv_open() will create a new BDS with an empty name; if the BDS pointer is not NULL, that existing BDS will be reused (in the same way as bdrv_open() already did). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2014-02-20util: Split out exec_dir from os_find_datadirFam Zheng1-0/+1
With this change, main() calls qemu_init_exec_dir and uses argv[0] to init exec_dir. The saved value can be retrieved with qemu_get_exec_dir later. It will be reused by module loading. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-02-17Use error_is_set() only when necessaryMarkus Armbruster1-4/+4
error_is_set(&var) is the same as var != NULL, but it takes whole-program analysis to figure that out. Unnecessarily hard for optimizers, static checkers, and human readers. Dumb it down to obvious. Gets rid of several dozen Coverity false positives. Note that the obvious form is already used in many places. Signed-off-by: Markus Armbruster <armbru@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Andreas Färber <afaerber@suse.de> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-01-06qemu-option: Remove qemu_opts_create_nofailPeter Crosthwaite1-1/+1
This is a boiler-plate _nofail variant of qemu_opts_create. Remove and use error_abort in call sites. null/0 arguments needs to be added for the id and fail_if_exists fields in affected callsites due to argument inconsistency between the normal and no_fail variants. Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2013-12-13qemu-img: make progress output more accurate during convertPeter Lieven1-5/+21
the progress output is very bumpy if the input images contains a significant portion of unallocated sectors. This patch checks how much sectors are allocated a priori if progress output is selected. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-12-06qemu-img: decrease progress update interval on convertPeter Lieven1-1/+1
when doing very large jobs updating the progress only every 2% is too rare. Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-06qemu-img: round down request length to an aligned sectorPeter Lieven1-8/+24
this patch shortens requests to end at an aligned sector so that the next request starts aligned. [Squashed Peter's fix for bdrv_get_info() failure discussed on the mailing list. --Stefan] Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-05qemu-img: dynamically adjust iobuffer size during convertPeter Lieven1-3/+13
since the convert process is basically a sync operation it might be benificial in some case to change the hardcoded I/O buffer size to a greater value. This patch increases the I/O buffer size if the output driver advertises an optimal transfer length or discard alignment that is greater than the default buffer size of 2M. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-05qemu-img: fix usage instruction for qemu-img convertPeter Lieven1-1/+0
Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-05qemu-img: add support for skipping zeroes in input during convertPeter Lieven1-38/+42
we currently do not check if a sector is allocated during convert. This means if a sector is unallocated that we allocate a bounce buffer of zeroes, find out its zero later and do not write it in the best case. In the worst case this can lead to reading blocks from a raw device (like iSCSI) altough we could easily know via get_block_status that they are zero and simply skip them. This patch also fixes the progress output not being at 100% after a successful conversion. Signed-off-by: Peter Lieven <pl@kamp.de> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-04qemu-img: add -l for snapshot in convertWenchao Xia1-9/+35
Now qemu-img convert have similar options as qemu-nbd for internal snapshot. Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-12-04snapshot: distinguish id and name in load_tmpWenchao Xia1-2/+6
Since later this function will be used so improve it. The only caller of it now is qemu-img, and it is not impacted by introduce function bdrv_snapshot_load_tmp_by_id_or_name() that call bdrv_snapshot_load_tmp() twice to keep old search logic. bdrv_snapshot_load_tmp_by_id_or_name() return int to let caller know the errno, and errno will be used later. Also fix a typo in comments of bdrv_snapshot_delete(). Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28qemu-img: conditionally zero out target on convertPeter Lieven1-1/+9
If the target has_zero_init = 0, but supports efficiently writing zeroes by unmapping we call bdrv_make_zero to avoid fully allocating the target. This currently works only for iscsi. It can be extended to raw with BLKDISCARDZEROES for example. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-28qemu-img: add support for fully allocated imagesPeter Lieven1-3/+7
Signed-off-by: Peter Lieven <pl@kamp.de> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-11-15qemu-img: Fix overwriting 'ret' before usingFam Zheng1-3/+3
This patch moves ret assignment after reporting original error. We were lucky to pass qemu-iotests 048 (qemu-img compare case) but when I tried to run with TEST_DIR=/tmp (tmpfs), it fails with a "wrong" mismatch offset. This fixes two bugs. In the first if branch, setting ret to 1 before using it makes dead code in the next line: pnum is never added to mismatch offset even if ret was 0. In the other if branch, currently the output error is always -4: strerror(-4) -> Unknown error -4 Added regression test in case 048. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Amos Kong <akong@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Fam Zheng <famz@redhat.com>
2013-10-24qemu-img: add special exit code if bdrv_check is not supportedPeter Lieven1-1/+1
currently it is not possible to distinguish by exitcode if there has been an error or if bdrv_check is not supported by the image format. Change the exitcode from 1 to 63 for the latter case. Signed-off-by: Peter Lieven <pl@kamp.de> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12qemu-img: fix invalid JSONPaolo Bonzini1-1/+1
Single quotes for JSON are a QMP-ism, use real JSON in qemu-img output. Reported-by: Kevin Wolf <kwolf@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12qemu-img create: Emit filename on errorMax Reitz1-1/+1
bdrv_img_create generally does not emit the target filename, although this is pretty important information. Therefore, prepend its error message with the output filename (if an error occurs). Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12block: Error parameter for create functionsMax Reitz1-11/+5
Add an Error ** parameter to bdrv_create and its associated functions to allow more specific error messages. Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12block: Error parameter for open functionsMax Reitz1-7/+14
Add an Error ** parameter to bdrv_open, bdrv_file_open and associated functions to allow more specific error messages. Signed-off-by: Max Reitz <mreitz@redhat.com>
2013-09-12snapshot: distinguish id and name in snapshot deleteWenchao Xia1-4/+7
Snapshot creation actually already distinguish id and name since it take a structured parameter *sn, but delete can't. Later an accurate delete is needed in qmp_transaction abort and blockdev-snapshot-delete-sync, so change its prototype. Also *errp is added to tip error, but return value is kepted to let caller check what kind of error happens. Existing caller for it are savevm, delvm and qemu-img, they are not impacted by introducing a new function bdrv_snapshot_delete_by_id_or_name(), which check the return value and do the operation again. Before this patch: For qcow2, it search id first then name to find the one to delete. For rbd, it search name. For sheepdog, it does nothing. After this patch: For qcow2, logic is the same by call it twice in caller. For rbd, it always fails in delete with id, but still search for name in second try, no change to user. Some code for *errp is based on Pavel's patch. Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Signed-off-by: Pavel Hrdina <phrdina@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-12block: Image file option amendmentMax Reitz1-0/+84
This patch adds the "amend" option to qemu-img which allows changing image options on existing image files. It also adds the generic bdrv implementation which is basically just a wrapper for the image format specific function. Signed-off-by: Max Reitz <mreitz@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-09-06qemu-img: add a "map" subcommandPaolo Bonzini1-0/+191
This command dumps the metadata of an entire chain, in either tabular or JSON format. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06block: make bdrv_has_zero_init return false for copy-on-write-imagesPaolo Bonzini1-8/+1
This helps implementing is_allocated on top of get_block_status. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06qemu-img: always probe the input image for allocated sectorsPaolo Bonzini1-21/+19
qemu-img convert can assume "that sectors which are unallocated in the input image are present in both the output's and input's base images". However it is only doing this if the output image returns true for bdrv_has_zero_init(). Testing bdrv_has_zero_init() does not make much sense if the output image is copy-on-write, because a copy-on-write image is never initialized to zero (it is initialized to the content of the backing file). There is nothing here that makes has_zero_init images special. The input and output must be equal for the operation to make sense, and that's it. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06block: expect errors from bdrv_co_is_allocatedPaolo Bonzini1-2/+14
Some bdrv_is_allocated callers do not expect errors, but the fallback in qcow2.c might make other callers trip on assertion failures or infinite loops. Fix the callers to always look for errors. Cc: qemu-stable@nongnu.org Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06block: make bdrv_delete() staticFam Zheng1-13/+13
Manage BlockDriverState lifecycle with refcnt, so bdrv_delete() is no longer public and should be called by bdrv_unref() if refcnt is decreased to 0. This is an identical change because effectively, there's no multiple reference of BDS now: no caller of bdrv_ref() yet, only bdrv_new() sets bs->refcnt to 1, so all bdrv_unref() now actually delete the BDS. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-09-06add qemu-img convert -n option (skip target volume creation)Alexandre Derumier1-15/+38
Add a -n option to skip volume creation on qemu-img convert. This is useful for targets such as rbd / ceph, where the target volume may already exist; we cannot always rely on qemu-img convert to create the image, as dependent on the output format, there may be parameters which are not possible to specify through the qemu-img convert command line. Reviewed-by: Eric Blake <eblake@redhat.com> Signed-off-by: Alexandre Derumier <aderumier@odiso.com> Signed-off-by: Alex Bligh <alex@alex.org.uk> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-06ignore SIGPIPE in qemu-img and qemu-ioMORITA Kazutaka1-0/+4
This prevents the tools from being stopped when they write data to a closed connection in the other side. Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2013-08-06qemu-img: Error out for excess argumentsKevin Wolf1-7/+10
Don't silently ignore excess arguments at the end of the command line, but error out instead. This can catch typos like 'resize test.img + 1G', which doesn't increase the image size by 1G as intended, but truncates the image to 1G. Even for less dangerous commands, the old behaviour is confusing. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Laszlo Ersek <lersek@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-07-15block: Don't parse protocol from file.filenameKevin Wolf1-2/+2
One of the major reasons for doing something new for -blockdev and blockdev-add was that the old block layer code parses filenames instead of just taking them literally. So we should really leave it untouched when it's passing using the new interfaces (like -drive file.filename=...). This allows opening relative file names that contain a colon. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com>
2013-06-21qemu-img: Add missing GCC_FMT_ATTRStefan Weil1-1/+1
Signed-off-by: Stefan Weil <sw@weilnetz.de> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-06-07block: add image info query function bdrv_query_image_info()Wenchao Xia1-5/+6
This patch adds function bdrv_query_image_info(), which will retrieve image info in qmp object format. The implementation is based on the code moved from qemu-img.c, but uses block layer function to get snapshot info. Signed-off-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>