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2014-09-22async: aio_context_new(): Handle event_notifier_init failureChrysostomos Nanakos
On a system with a low limit of open files the initialization of the event notifier could fail and QEMU exits without printing any error information to the user. The problem can be easily reproduced by enforcing a low limit of open files and start QEMU with enough I/O threads to hit this limit. The same problem raises, without the creation of I/O threads, while QEMU initializes the main event loop by enforcing an even lower limit of open files. This commit adds an error message on failure: # qemu [...] -object iothread,id=iothread0 -object iothread,id=iothread1 qemu: Failed to initialize event notifier: Too many open files in system Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: vhdx - fix reading beyond pointer during image creationJeff Cody
In vhdx_create_metadata(), we allocate 40 bytes to entry_buffer for the various metadata table entries. However, we write out 64kB from that buffer into the new file. Only write out the correct 40 bytes. Signed-off-by: Jeff Cody <jcody@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: delete cow block driverStefan Hajnoczi
This patch removes support for the cow file format. Normally we do not break backwards compatibility but in this case there is no impact and it is the most logical option. Extraordinary claims require extraordinary evidence so I will show why removing the cow block driver is the right thing to do. The cow file format is the disk image format for Usermode Linux, a way of running a Linux system in userspace. The performance of UML was never great and it was hacky, but it enjoyed some popularity before hardware virtualization support became mainstream. QEMU's block/cow.c is supposed to read this image file format. Unfortunately the file format was underspecified: 1. Earlier Linux versions used the MAXPATHLEN constant for the backing filename field. The value of MAXPATHLEN can change, so Linux switched to a 4096 literal but QEMU has a 1024 literal. 2. Padding was not used on the header struct (both in the Linux kernel and in QEMU) so the struct layout varied across architectures. In particular, i386 and x86_64 were different due to int64_t alignment differences. Linux now uses __attribute__((packed)), QEMU does not. Therefore: 1. QEMU cow images do not conform to the Linux cow image file format. 2. cow images cannot be shared between different host architectures. This means QEMU cow images are useless and QEMU has not had bug reports from users actually hitting these issues. Let's get rid of this thing, it serves no purpose and no one will be affected. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-id: 1410877464-20481-1-git-send-email-stefanha@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block/archipelago: Fix typo in qemu_archipelago_truncate()Chrysostomos Nanakos
Fix a typo introduced by 94c80a438c85f2c19698547fbb115ea46d80c5f1 Signed-off-by: Chrysostomos Nanakos <cnanakos@grnet.gr> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: Add test_identify case to ahci-test.John Snow
Utilizing all of the bring-up code in pci_enable and hba_enable, this test issues a simple IDENTIFY command via the HBA and retrieves the response via the PIO receive mechanisms of the HBA. Bugs: The DPS interrupt (Descriptor Processed Status) does not currently get set. This will need to be adjusted in a future patch series when the AHCI DMA pathways are reworked to allow the feature, which may be utilized by OSX guests. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-9-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: Add test_hba_enable to ahci-test.John Snow
This test engages the HBA functionality and initializes values to sane defaults to allow for minimal HBA functionality. Buffers are allocated and pointers are updated to allow minimal I/O commands to complete as expected. Error registers and responses are sanity checked for specification adherence. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-8-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: Add test_hba_spec to ahci-test.John Snow
Add a test routine that checks the boot-up values of the HBA configuration memory space against the AHCI 1.3 specification and Intel ICH9 data sheet (for Q35 machines) for adherence and sane values. The HBA is not yet engaged or put into the idle state. [Replaced g_assert_false(...) with g_assert(!...) for glib <2.38 compatibility, reported by Peter Maydell <peter.maydell@linaro.org>. --Stefan] Signed-off-by: John Snow <jsnow@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Message-id: 1408643079-30675-7-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: properly shadow the TFD registerJohn Snow
In a real AHCI device, several S/ATA registers are mirrored or shadowed within the AHCI register set. These registers are not updated synchronously for each read access, but are instead updated after a Device-to-Host Register FIS packet is received. The D2H FIS contains the values from these registers on the device. In QEMU, by reaching directly into the device to grab these bits before they are "sent," we may introduce race conditions where unexpected values are present "before they are sent" which could cause issues for some guests, particularly if an attempt is made to read the PxTFD register prior to enabling the port, where incorrect values will be read. This patch also addresses the boot-time values for the PxTFD and PxSIG registers to bring them in line with the AHCI 1.3 specification. Lastly, several fields (PxTFD, PxSIG and PxSACT) are read-only, and any attempts to write to them should be ignored. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-6-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: add test_pci_enable to ahci-test.John Snow
This adds a test wherein we engage the PCI AHCI device and ensure that the memory region for the HBA functionality is now accessible. Under Q35 environments, additional PCI configuration is performed to ensure that the HBA functionality will become usable. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-5-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: Add test_pci_spec to ahci-test.John Snow
Adds a specification adherence test for AHCI where the boot-up values for the PCI configuration space are compared against the AHCI 1.3 specification. This test does not itself attempt to engage the device. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-4-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: MSI capability should be at 0x80, not 0x50.John Snow
In the Intel ICH9 data sheet, the MSI capability offset in the PCI configuration space for ICH9 AHCI devices is specified to be 0x80. Further, the PCI capability pointer should always point to 0x80 in ICH9 devices, despite the fact that AHCI 1.3 specifies that it should be pointing to PMCAP (Which in this instance would be 0x70) to maintain adherence to the Intel data sheet specifications and real observed behavior. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-3-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ahci: Adding basic functionality qtest.John Snow
Currently, there is no qtest to test the functionality of the AHCI functionality present within the Q35 machine type. This patch adds a skeleton for an AHCI test suite, and adds a simple sanity-check test case where we identify that the AHCI device is present, then disengage the virtual machine. Signed-off-by: John Snow <jsnow@redhat.com> Message-id: 1408643079-30675-2-git-send-email-jsnow@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22layout: Add generators for refcount table and blocksMaria Kustova
Refcount structures are placed in clusters randomly selected from all unallocated host clusters. Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Maria Kustova <maria.k@catit.be> Reviewed-by: Fam Zheng <famz@redhat.com> Message-id: 7e2f38608db6fba2da53997390b19400d445c45d.1408450493.git.maria.k@catit.be Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22fuzz: Add fuzzing functions for entries of refcount table and blocksMaria Kustova
Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Maria Kustova <maria.k@catit.be> Message-id: c9f4027b6f401c67e9d18f94aed29be445e81d48.1408450493.git.maria.k@catit.be Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22docs: List all image elements currently supported by the fuzzerMaria Kustova
Reviewed-by: Fam Zheng <famz@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Maria Kustova <maria.k@catit.be> Message-id: cb71485d0f55d1d8401eebaead8324eb78673060.1408450493.git.maria.k@catit.be Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qapi/block-core: Add "new" qcow2 optionsMax Reitz
qcow2 supports more than four options by now, add the new options (overlap check mode and metadata cache size) Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1408557576-14574-5-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qcow2: Add overlap-check.template optionMax Reitz
Being able to set the overlap-check option to a string and then refine it via the overlap-check.* options is a nice idea for the command line but does not work so well for non-flattened dicts. In that case, one can only specify either but not both, so add a field to overlap-check.* which does the same as directly specifying overlap-check but can be used in conjunction with the other fields in non-flattened dicts. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1408557576-14574-4-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qapi: Allow enums in anonymous unionsMax Reitz
Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1408557576-14574-3-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qcow2: Fix leak of QemuOpts in qcow2_open()Max Reitz
Currently, the QemuOpts object opts is leaked if anything fails from its creation up to and including the image repair block. Fix this by freeing that object in the fail path. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Message-id: 1408557576-14574-2-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22hmp: fix memory leak at hmp_info_block_jobs()Gonglei
Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Message-id: 1410874615-14292-1-git-send-email-arei.gonglei@huawei.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22image-fuzzer: Trivial readability and formatting improvementsMaria Kustova
Signed-off-by: Maria Kustova <maria.k@catit.be> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22iotests: Add more tests for qcow2 corruptionMax Reitz
Add tests for unaligned L1/L2/reftable entries and non-fatal corruption reports. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1409926039-29044-6-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qcow2: Check L1/L2/reftable entries for alignmentMax Reitz
Offsets taken from the L1, L2 and refcount tables are generally assumed to be correctly aligned. However, this cannot be guaranteed if the image has been written to by something different than qemu, thus check all offsets taken from these tables for correct cluster alignment. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1409926039-29044-5-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qcow2: Use qcow2_signal_corruption() for overlapsMax Reitz
Use the new function in case of a failed overlap check. This changes output in case of corruption, so adapt iotest 060's reference output accordingly. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Message-id: 1409926039-29044-4-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qcow2: Add qcow2_signal_corruption()Max Reitz
Add a helper function for easily marking an image corrupt (on fatal corruptions) while outputting an informative message to stderr and via QAPI. Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Message-id: 1409926039-29044-3-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qapi/block: Add "fatal" to BLOCK_IMAGE_CORRUPTEDMax Reitz
Not every BLOCK_IMAGE_CORRUPTED event must be fatal; for example, when reading from an image, they should generally not be. Nonetheless, even an image only read from may of course be corrupted and this can be detected during normal operation. In this case, a non-fatal event should be emitted, but the image should not be marked corrupt (in accordance to "fatal" set to false). Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1409926039-29044-2-git-send-email-mreitz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qapi: Sort items in BlockdevOptions definitionFam Zheng
Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1410415798-20673-4-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qapi: Sort BlockdevDriver enum data listFam Zheng
Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1410415798-20673-3-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Introduce "null" driversFam Zheng
This is an analogue to Linux null_blk. It can be used for testing or benchmarking block device emulation and general block layer functionalities such as coroutines and throttling, where disk IO is not necessary or wanted. Use null-aio:// for AIO version, and null-co:// for coroutine version. [Resolved conflict with Fam's async bdrv_aio_cancel() series: 1. Drop .bdrv_aio_cancel() since it is now done by block.c 2. Rename qemu_aio_release() to qemu_aio_unref() --Stefan] Signed-off-by: Fam Zheng <famz@redhat.com> Reviewed-by: Benoît Canet <benoit.canet@nodalink.com> Reviewed-by: Eric Blake <eblake@redhat.com> Message-id: 1410415798-20673-2-git-send-email-famz@redhat.com Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22aio-win32: avoid out-of-bounds access to the events arrayPaolo Bonzini
If ret is WAIT_TIMEOUT and there was an event returned by select(), we can write to a location after the end of the array. But in that case we can retry the WaitForMultipleObjects call with the same set of events, so just move the event[ret - WAIT_OBJECT_0] assignment inside the existin conditional. Reported-by: TeLeMan <geleman@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: TeLeMan <geleman@gmail.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qdev-monitor: fix segmentation fault on qdev_device_help()Gonglei
Normally, qmp_device_list_properties() may return NULL when a device haven't special properties excpet Object and DeviceState properties, such as virtio-balloon-device. We just need check local_err instead of prop_list. Example: Segmentation fault (core dumped) The backtrace as below: Program received signal SIGSEGV, Segmentation fault. 0x00005555559af1a8 in error_get_pretty (err=0x0) at util/error.c:152 152 return err->msg; (gdb) bt func=0x55555574a6ca <device_help_func>, opaque=0x0, abort_on_failure=0) at util/qemu-option.c:1072 Signed-off-by: Gonglei <arei.gonglei@huawei.com> Reviewed-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Rename qemu_aio_release -> qemu_aio_unrefFam Zheng
Suggested-by: Benoît Canet <benoit.canet@irqsave.net> Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Drop AIOCBInfo.cancelFam Zheng
Now that all the implementations are converted to asynchronous version and we can emulate synchronous cancellation with it. Let's drop the unused member. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22ide: Convert trim_aiocb_info.cancel to .cancel_asyncFam Zheng
We know that either bh is scheduled or ide_issue_trim_cb will be called again, so we just set i, j and ret to the right values. In both cases, ide_trim_bh_cb will be called. Also forward the cancellation to the iocb->aiocb which we get from bdrv_aio_discard. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22win32-aio: Drop win32_aiocb_info.cancelFam Zheng
Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22sheepdog: Convert sd_aiocb_info.cancel to .cancel_asyncFam Zheng
Also drop the now unused SheepdogAIOCB.finished field. Note that this aio is internal to sheepdog driver and has NULL cb and opaque, and should be unused at all. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22rbd: Drop rbd_aiocb_info.cancelFam Zheng
And also drop the now unused "cancelled" field. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22quorum: Convert quorum_aiocb_info.cancel to .cancel_asyncFam Zheng
Before, we cancel all the child requests with bdrv_aio_cancel, then free the acb.. Now we just kick off asynchronous cancellation of child requests and return, we know quorum_aio_cb will be called later, so in the end quorum_aio_finalize will take care of calling the caller's cb. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22quorum: fix quorum_aio_cancel()Liu Yuan
For a fifo read pattern, we only have one running aio (possible other cases that has less number than num_children in the future), so we need to check if .acb is NULL against bdrv_aio_cancel() to avoid segfault. Cc: Eric Blake <eblake@redhat.com> Cc: Benoit Canet <benoit@irqsave.net> Cc: Kevin Wolf <kwolf@redhat.com> Cc: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Liu Yuan <namei.unix@gmail.com> Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22qed: Drop qed_aiocb_info.cancelFam Zheng
Also drop the now unused ->finished field. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22curl: Drop curl_aiocb_info.cancelFam Zheng
Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22blkverify: Drop blkverify_aiocb_info.cancelFam Zheng
Also the finished pointer is not used any more. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22blkdebug: Drop blkdebug_aiocb_info.cancelFam Zheng
Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22archipelago: Drop archipelago_aiocb_info.cancelFam Zheng
The cancelled flag is no longer useful. Later the request will complete as before, and cb will be called. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22iscsi: Convert iscsi_aiocb_info.cancel to .cancel_asyncFam Zheng
Also drop the unused field "canceled". Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22dma: Convert dma_aiocb_info.cancel to .cancel_asyncFam Zheng
Just forward the request to bdrv_aio_cancel_async. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22linux-aio: Convert laio_aiocb_info.cancel to .cancel_asyncFam Zheng
Just call io_cancel (2), if it fails, it means the request is not canceled, so the event loop will eventually call qemu_laio_process_completion. In qemu_laio_process_completion, change to call the cb unconditionally. It is required by bdrv_aio_cancel_async. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22thread-pool: Convert thread_pool_aiocb_info.cancel to cancel_asyncFam Zheng
The .cancel_async shares the same the first half with .cancel: try to steal the request if not submitted yet. In this case set the elem to THREAD_DONE status and ret to -ECANCELED, which means thread_pool_completion_bh will call the cb with -ECANCELED. If the request is already submitted, do nothing, as we know the normal completion will happen in the future. Testing code update: Before, done_cb is only called if the request is already submitted by thread pool. Now done_cb is always called, even before it is submitted, because we emulate bdrv_aio_cancel with bdrv_aio_cancel_async. So also update the test criteria accordingly. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Drop bdrv_em_aiocb_info.cancelFam Zheng
Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2014-09-22block: Drop bdrv_em_co_aiocb_info.cancelFam Zheng
Also drop the now unused ->done pointer. Signed-off-by: Fam Zheng <famz@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>