Report from valgrind:
==19521== Source and destination overlap in memcpy(0x31d38938, 0x31d38938, 64)
==19521== at 0x4A0A343: memcpy@@GLIBC_2.14 (in
/usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==19521== by 0x42774E: virtio_blk_device_init (virtio-blk.c:686)
==19521== by 0x46EE9E: virtio_device_init (virtio.c:1158)
==19521== by 0x25405E: device_realize (qdev.c:178)
==19521== by 0x2559B5: device_set_realized (qdev.c:699)
==19521== by 0x3A819B: property_set_bool (object.c:1315)
==19521== by 0x3A6CE0: object_property_set (object.c:803)
Valgrind is right: blk == &s->blks, so it is a memcpy of 64 byte with
source == destination which can be removed.
Reported-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The following sequence happens:
- the SeaBIOS virtio-blk driver does not support the WCE feature, which
causes QEMU to disable writeback caching
- the Linux virtio-blk driver resets the device, finds WCE is available
but writeback caching is disabled; tells block layer to not send cache
flush commands
- the Linux virtio-blk driver sets the DRIVER_OK bit, which causes
writeback caching to be re-enabled, but the Linux virtio-blk driver does
not know of this side effect and cache flushes remain disabled
The bug is at the third step. If the guest does know about CONFIG_WCE,
QEMU should ignore the WCE feature's state. The guest will control the
cache mode solely using configuration space. This change makes Linux
do flushes correctly, but Linux will keep SeaBIOS's writethrough mode.
Hence, whenever the guest is reset, the cache mode of the disk should
be reset to whatever was specified in the "-drive" option. With this
change, the Linux virtio-blk driver finds that writeback caching is
enabled, and tells the block layer to send cache flush commands
appropriately.
Reported-by: Rusty Russell <rusty@au1.ibm.com
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
# By Stefan Hajnoczi (4) and others
# Via Stefan Hajnoczi
* stefanha/block:
dataplane: refuse to start if device is already in use
dataplane: enable virtio-blk x-data-plane=on live migration
migration: fix spice migration
migration: notify migration state before starting thread
block: Repair the throttling code.
gluster: Add image resize support
Message-id: 1375112172-24863-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
The category will be used to sort the devices displayed in
the command line help.
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Message-id: 1375107465-25767-4-git-send-email-marcel.a@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Although the dataplane thread does not cooperate with dirty memory
logging yet it's fairly easy to temporarily disable dataplane during
live migration. This way virtio-blk can live migrate when
x-data-plane=on.
The dataplane thread will restart after migration is cancelled or if the
guest resuming virtio-blk operation after migration completes.
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This clean the init and the exit functions and rename virtio_common_cleanup
to virtio_cleanup.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This remove the function pointer in VirtIODevice, and use only
VirtioDeviceClass function pointer.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-5-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Minor fixes to documentation and code comments.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
