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  1. 03 4月, 2019 17 次提交
  3. 29 3月, 2019 3 次提交
  5. 28 3月, 2019 4 次提交
  7. 27 3月, 2019 3 次提交
  9. 26 3月, 2019 13 次提交
    • L
      qemu_hotplug: don't shutdown net device until the guest has released it · 34086fc5
      由 Laine Stump 提交于 
      For [some unknown reason, possibly/probably pure chance], Net devices
have been taken offline and their bandwidth tc rules cleared as the
very first operation when detaching the device. This is contrary to
every other type of device, where all hostside teardown is delayed
until we receive the DEVICE_DELETED event back from qemu, indicating
that the guest has finished with the device.

This patch delays these two operations until receipt of
DEVICE_DELETED, which removes an ugly wart from
qemuDomainDetachDeviceLive(), and also seems to be a more correct
sequence of events.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      34086fc5
    • L
      qemu_hotplug: delay sending DEVICE_REMOVED event until after *all* teardown · 78b03a77
      由 Laine Stump 提交于 
      The VIR_DOMAIN_EVENT_ID_DEVICE_REMOVED event is sent after qemu has
responded to a device_del command with a DEVICE_DELETED event. Before
queuing the event, *some* of the final teardown of the device's
trappings in libvirt is done, but not *all* of it. As a result, an
application may receive and process the DEVICE_REMOVED event before
libvirt has really finished with it.

Usually this doesn't cause a problem, but it can - in the case of the
bug report referenced below, vdsm is assigning a PCI device to a guest
with managed='no', using livirt's virNodeDeviceDetachFlags() and
virNodeDeviceReAttach() APIs. Immediately after receiving a
DEVICE_REMOVED event from libvirt signalling that the device had been
successfully unplugged, vdsm would cal virNodeDeviceReAttach() to
unbind the device from vfio-pci and rebind it to the host driverm but
because the event was received before libvirt had completely finished
processing the removal, that device was still on the "activeDevs"
list, and so virNodeDeviceReAttach() failed.

Experimentation with additional debug logs proved that libvirt would
always end up dispatching the DEVICE_REMOVED event before it had
removed the device from activeDevs (with a *much* greater difference
with managed='yes', since in that case the re-binding of the device
occurred after queuing the device).

Although the case of hostdev devices is the most extreme (since there
is so much involved in tearing down the device), *all* device types
suffer from the same problem - the DEVICE_REMOVED event is queued very
early in the qemuDomainRemove*Device() function for all of them,
resulting in a possibility of any application receiving the event
before libvirt has really finished with the device.

The solution is to save the device's alias (which is the only piece of
info from the device object that is needed for the event) at the
beginning of processing the device removal, and then queue the event
as a final act before returning. Since all of the
qemuDomainRemove*Device() functions (except
qemuDomainRemoveChrDevice()) are now called exclusively from
qemuDomainRemoveDevice() (which selects which of the subordinates to
call in a switch statement based on the type of device), the shortest
route to a solution is to doing the saving of alias, and later
queueing of the event, in the higher level qemuDomainRemoveDevice(),
and just completely remove the event-related code from all the
subordinate functions.

The single exception to this, as mentioned before, is
qemuDomainRemoveChrDevice(), which is still called from somewhere
other than qemuDomainRemoveDevice() (and has a separate arg used to
trigger different behavior when the chr device has targetType ==
GUESTFWD), so it must keep its original behavior intact, and must be
treated differently by qemuDomainRemoveDevice() (similar to the way
that qemuDomainDetachDeviceLive() treats chr and lease devices
differently from all the others).

Resolves: https://bugzilla.redhat.com/1658198Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      78b03a77
    • L
      qemu_hotplug: consolidate all common detach code in qemuDomainDetachDeviceLive · dd60bd62
      由 Laine Stump 提交于 
      Now that all the qemuDomainDetachPrep*() functions look nearly
identical at the end, we can put one copy of that identical code in
qemuDomainDetachDeviceLive() at the point after the individual prep
functions have been called, and remove the duplicated code from all
the prep functions. The code to locate the target "detach" device
based on the "match" device remains, as do all device-type-specific
validations.

Unfortunately there are a few things going on at once in this patch,
which makes it a bit more difficult to follow than the others; it was
just impossible to do the changes in stages and still have a
buildable/testable tree at each step.

The other changes of note:

* The individual prep functions no longer need their driver or async
  args, so those are removed, as are the local "ret" variables, since
  in all cases the functions just directly return -1 or 0.

* Some of the prep functions were checking for a valid alias and/or
  for attempts to detach a multifunction PCI device, but not all. In
  fact, both checks are valid (or at least harmless) for *all* device
  types, so they are removed from the prep functions, and done a
  single time in the common function.

  (any attempts to *create* an alias when there isn't one has been
  removed, since that is doomed to failure anyway; the only way the
  device wouldn't have an alias is if 1) the domain was created by
  calling virsh qemu-attach to attach an existing qemu process to
  libvirt, and 2) the qemu command that started said process used "old
  style" arguments for creating devices that didn't have any device
  ids. Even if we constructed a device id for one of these devices,
  qemu wouldn't recognize it in the device_del command anyway, so we
  may as well fail earlier with "device missing alias" rather than
  failing later with "couldn't delete device net0".)

* Only one type of device has shutdown code that must not be called
  until after *all* validation of the device is done (including
  checking for multifunction PCI and valid alias, which is done in the
  toplevel common code). For this reason, the Net function has been
  split in two, with the 2nd half (qemuDomainDetachShutdownNet())
  called from the common function, right before sending the delete
  command to qemu.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      dd60bd62
    • L
      qemu_hotplug: audit *all* auditable device types in qemuDomainRemoveAuditDevice · 444c5e7c
      由 Laine Stump 提交于 
      Although all hotpluggable devices other than lease, controller,
watchdof, and vsock can be audited, and *are* audited when an unplug
is successful, only disk, net, and hostdev were actually being audited
on failure.

This patch corrects that omission.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      444c5e7c
    • L
      qemu_hotplug: new function qemuDomainRemoveAuditDevice() · b914e0ec
      由 Laine Stump 提交于 
      This function can be called with a virDomainDevicePtr and whether or
not the removal was successful, and it will call the appropriate
virDomainAudit*() function with the appropriate args for whatever type
of device it's given (or do nothing, if that's appropriate). This
permits generalizing some code that currently has a separate copy for
each type of device.

NB: Although the function initially will be called only with
success=false, that has been made an argument so that in the future
(when the qemuDomainRemove*Device() functions have had their common
functionality consolidated into qemuDomainRemoveDevice()), this new
common code can call qemuDomainRemoveAuditDevice() for all types.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      b914e0ec
    • L
      qemu_hotplug: rename Chr and Lease Detach functions · e1949c70
      由 Laine Stump 提交于 
      qemuDomainDetachDeviceChr and qemuDomainDetachDeviceLease are more
consistent with each other.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      e1949c70
    • L
      qemu_hotplug: standardize the names/args/calling of qemuDomainDetach*() · b6a53bf9
      由 Laine Stump 提交于 
      Most of these functions will soon contain only some setup for
detaching the device, not the detach code proper (since that code is
identical for these devices). Their device specific functions are all
being renamed to qemuDomainDetachPrep*(), where * is the
name of that device's data member in the virDomainDeviceDef
object.

Since there will be other code in qemuDomainDetachDeviceLive() after
the calls to qemuDomainDetachPrep*() that could still fail, we no
longer directly set "ret" with the return code from
qemuDomainDetachPrep*() functions, but simply return -1 on
failure, and wait until the end of qemuDomainDetachDeviceLive() to set
ret = 0.

Along with the rename, qemuDomainDetachPrep*() functions are also
given similar arglists, including an arg called "match" that points to
the proto-object of the device we want to delete, and another arg
"detach" that is used to return a pointer to the actual object that
will be (for now *has been*) detached. To make sure these new args
aren't confused with existing local pointers that sometimes had the
same name (detach), the local pointer to the device is now named after
the device type ("controller", "disk", etc). These point to the same
place as (*detach)->data.blah, it's just easier on the eyes to have,
e.g., "disk->dst" rather than "(*detach)->data.disk-dst".
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      b6a53bf9
    • L
      qemu_hotplug: separate Chr|Lease from other devices in DetachDevice switch · 2ec6faea
      由 Laine Stump 提交于 
      The Chr and Lease devices have detach code that is too different from
the other device types to handle with common functionality (which will
soon be added at the end of qemuDomainDetachDeviceLive(). In order to
make this difference obvious, move the cases for those two device
types to the top of the switch statement in
qemuDomainDetachDeviceLive(), have the cases return immediately so the
future common code at the end of the function will be skipped, and
also include some hopefully helpful comments to remind future
maintainers why these two device types are treated differently.

Any attempt to detach an unsupported device type should also skip the
future common code at the end of the function, so the case for
unsupported types is similarly changed from a simple break to a return
-1.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      2ec6faea
    • L
      qemu_hotplug: rename dev to match in qemuDomainDetachDeviceLive · c4d6a121
      由 Laine Stump 提交于 
      I'm about to add a second virDomainDeviceDef to this function that
will point to the actual device in the domain object. while this is
just a partially filled-in example of what to look for. Naming it
match will make the code easier to follow.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      c4d6a121
    • L
      qemu_hotplug: make Detach functions called only from qemu_hotplug.c static · 637d72f9
      由 Laine Stump 提交于 
      These are no longer called from qemu_driver.c, since the function that
called them (qemuDomainDetachDeviceLive()) has been moved to
qemu_hotplug.c, and they are no longer called from testqemuhotplug.c
because it now just called qemuDomainDetachDeviceLive() instead of all
the subordinate functions.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      637d72f9
    • L
      qemu_hotplug: pull qemuDomainUpdateDeviceList out of qemuDomainDetachDeviceLive · b2049418
      由 Laine Stump 提交于 
      qemuDomainDetachDeviceLive() is called from two places in
qemu_driver.c, and qemuDomainUpdateDeviceList() is called from the
end of qemuDomainDetachDeviceLive(), which is now in qemu_hotplug.c

This patch replaces the single call to qemuDomainUpdateDeviceList()
with two calls to it immediately after return from
qemuDomainDetachDeviceLive(). This is only done if the return from
that function is exactly 0, in order to exactly preserve previous
behavior.

Removing that one call from qemuDomainDetachDeviceList() will permit
us to call it from the test driver hotplug test, replacing the
separate calls to qemuDomainDetachDeviceDiskLive(),
qemuDomainDetachChrDevice(), qemuDomainDetachShmemDevice() and
qemuDomainDetachWatchdog(). We want to do this so that part of the
common functionality of those three functions (and the rest of the
device-specific Detach functions) can be pulled up into
qemuDomainDetachDeviceLive() without breaking the test. (This is done
in the next patch).

NB: Almost certainly this is "not the best place" to call
qemuDomainUpdateDeviceList() (actually, it is provably the *wrong*
place), since it's purpose is to retrieve an "up to date" list of
aliases for all devices from qemu, and if the guest OS hasn't yet
processed the detach request, the now-being-removed device may still
be on that list. It would arguably be better to instead call
qemuDomainUpdateDevicesList() later during the response to the
DEVICE_DELETED event for the device. But removing the call from the
current point in the detach could have some unforeseen ill effect due
to changed timing, so the change to move it into
qemuDomainRemove*Device() will be done in a separate patch (in order
to make it easily revertible in case it causes a regression).
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      b2049418
    • L
      qemu_hotplug: remove extra function in middle of DetachController call chain · e4d96324
      由 Laine Stump 提交于 
      qemuDomainDetachDeviceControllerLive() just checks if the controller
type is SCSI, and then either returns failure, or calls
qemuDomainDetachControllerDevice().

Instead, lets just check for type != SCSI at the top of the latter
function, and call it directly.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      e4d96324
    • L
      qemu_hotplug: move qemuDomainDetachDeviceLive() to qemu_hotplug.c · 6a9c3fba
      由 Laine Stump 提交于 
      This function is going to take on some of the functionality of its
subordinate functions, which all live in qemu_hotplug.c.

qemuDomainDetachDeviceControllerLive() is only called from
qemuDomainDetachDeviceLive() (and will soon be merged into
qemuDomainDetachControllerDevice(), which is in qemu_hotplug.c), so
it is also moved.
Signed-off-by: NLaine Stump <laine@laine.org>
ACKed-by: NPeter Krempa <pkrempa@redhat.com>
      6a9c3fba