Add code to check availability of PCI passhthrough using VFIO and the
legacy KVM passthrough and use it when starting VMs and hotplugging
devices to live machine.
I recently patches the callers to virPCIDeviceReset() to not call it
if the current driver for a device was vfio-pci (since that driver
will always reset the device itself when appropriate. At the time, Dan
Berrange suggested that I could instead modify virPCIDeviceReset
to check the currently bound driver for the device, and decide
for itself whether or not to go ahead with the reset.
This patch removes the previously added checks, and replaces them with
a check down in virPCIDeviceReset(), as suggested.
The functional difference here is that previously we were deciding
based on either the hostdev configuration or the value of
stubDriverName in the virPCIDevice object, but now we are actually
comparing to the "driver" link in the device's sysfs entry
directly. In practice, both should be the same.
Recent changes uncovered a possibility that 'last_processed_hostdev_vf'
was set to -1 in 'qemuPrepareHostdevPCIDevices' and would cause problems
in for loop end condition in the 'resetvfnetconfig' label if the
variable was never set to 'i' due to 'qemuDomainHostdevNetConfigReplace'
failure.
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A loop in qemuPrepareHostdevPCIDevices() intended to cycle through all
the objects on the list pcidevs was doing "while (listcount > 0)", but
nothing in the body of the loop was reducing the size of the list - it
was instead removing items from a *different* list. It has now been
safely changed to a for() loop.
(This isn't as bad as it sounds - it's only a problem in case of an
OOM error.)
qemuGetActivePciHostDeviceList() had been creating a list that
contained pointers to objects that were also on the activePciHostdevs
list. In case of an OOM error, this newly created list would be
virObjectUnref'ed, which would cause everything on the list to be
freed. But all of those objects would still be on the
activePciHostdevs list, which could have very bad consequences if that
list was ever again accessed.
The solution used here is to populate the new list with *copies* of
the objects from the original list. It turns out that on return from
qemuGetActivePciHostDeviceList(), the caller would almost immediately
go through all the device objects and "steal" them (i.e. remove the
pointer from the list but not delete it) all from either one list or
the other; we now instead just *delete* (remove from the list and
free) each device from one list or the other, so in the end we have
the same state.
The driver arg to virPCIDeviceDetach is no longer used (the name of the stub driver is now set in the virPCIDevice object, and virPCIDeviceDetach retrieves it from there). Remove it.
I just learned that VFIO resets PCI devices when they are assigned to
guests / returned to the host, so it is redundant for libvirt to reset
the devices. This patch inhibits calling virPCIDeviceReset to devices
that will be/were assigned using VFIO.
Previously stubDriver was always set from a string literal, so it was
okay to use a const char * that wasn't freed when the virPCIDevice was
freed. This will not be the case in the near future, so it is now a
char* that is allocated in virPCIDeviceSetStubDriver() and freed
during virPCIDeviceFree().
This should resolve:
https://bugzilla.redhat.com/show_bug.cgi?id=959191
The problem was that qemuUpdateActivePciHostdevs was returning 0
(success) when no hostdevs were present, but would otherwise return -1
(failure) even when it completed successfully. It is only called from
qemuProcessReconnect(), and when qemuProcessReconnect got back an
error, it would not only stop reconnecting, but would terminate the
guest qemu process "to remove danger of it ending up running twice if
user tries to start it again later".
(This bug was introduced in commit 011cf7ad, which was pushed between
v1.0.2 and v1.0.3, so all maintenance branches from v1.0.3 up to 1.0.5
will need this one line patch applied.)
This adds the shared device entry when starting domain (more
exactly, when preparing host devices), and remove the entry
when destroying domain (when reattaching host devices).
Although virtio-scsi supports SCSI PR (Persistent Reservations),
the device on host may do not support it. To avoid losing data,
Just like PCI and USB pass through devices, only one live guest
is allowed per SCSI host pass through device."
Signed-off-by: Han Cheng <hanc.fnst@cn.fujitsu.com>
virPCIDeviceReattach and virPCIDeviceUnbindFromStub (called by
virPCIDeviceReattach) had previously required the name of the stub
driver as input. This is unnecessary, because the name of the driver
the device is currently bound to can be found by looking at the link:
/sys/bus/pci/dddd:bb:ss.ff/driver
Instead of requiring that the name of the expected stub driver name
and only unbinding if that one name is matched, we no longer take a
driver name in the arglist for either of these
functions. virPCIDeviceUnbindFromStub just compares the name of the
currently bound driver to a list of "well known" stubs (right now
contains "pci-stub" and "vfio-pci" for qemu, and "pciback" for xen),
and only performs the unbind if it's one of those devices.
This allows virsh nodedevice-reattach to work properly across a
libvirtd restart, and fixes a couple of cases where we were
erroneously still hard-coding "pci-stub" as the drive name.
For some unknown reason, virPCIDeviceReattach had been calling
modprobe on the stub driver prior to unbinding the device. This was
problematic because we no longer know the name of the stub driver in
that function. However, it is pointless to probe for the stub driver
at that time anyway - because the device is bound to the stub driver,
we are guaranteed that it is already loaded, and so that call to
modprobe has been removed.
This isn't strictly speaking a bugfix, but I realized I'd gotten a bit
too verbose when I chose the names for
VIR_DOMAIN_HOSTDEV_PCI_BACKEND_TYPE_*. This shortens them all a bit.
If the config for a device has specified <driver name='vfio'/>,
"backend" in the pci part of the hostdev object will be set to
..._VFIO. In this case, when creating a virPCIDevice set the
stubDriver to "vfio-pci", otherwise set it to "pci-stub". We will rely
on the lower levels to report an error if the vfio driver isn't
loaded.
The detach/attach functions in virpci.c will pay attention to the
stubDriver setting in the device, and bind/unbind the appropriate
driver when preparing hostdevs for the domain.
Note that we don't yet attempt to do anything to mark active any other
devices in the same vfio "group" as a single device that is being
marked active. We do need to do that, but in order to get basic VFIO
functionality testing sooner rather than later, initially we'll just
live with more cryptic errors when someone tries to do that.
There will soon be other items related to pci hostdevs that need to be
in the same part of the hostdevsubsys union as the pci address (which
is currently a single member called "pci". This patch replaces the
single member named pci with a struct named pci that contains a single
member named "addr".
Currently the activePciHostdevs, inactivePciHostdevsd and
activeUsbHostdevs lists are all implicitly protected by the
QEMU driver lock. Now that the lists all inherit from the
virObjectLockable, we can make the locking explicit, removing
the dependency on the QEMU driver lock for correctness.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
To allow modifications to the lists to be synchronized, convert
virPCIDeviceList and virUSBDeviceList into virObjectLockable
classes. The locking, however, will not be self-contained. The
users of these classes will have to call virObjectLock/Unlock
in the critical regions.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently the virQEMUDriverPtr struct contains an wide variety
of data with varying access needs. Move all the static config
data into a dedicated virQEMUDriverConfigPtr object. The only
locking requirement is to hold the driver lock, while obtaining
an instance of virQEMUDriverConfigPtr. Once a reference is held
on the config object, it can be used completely lockless since
it is immutable.
NB, not all APIs correctly hold the driver lock while getting
a reference to the config object in this patch. This is safe
for now since the config is never updated on the fly. Later
patches will address this fully.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Pass stub driver name directly to pciDettachDevice and pciReAttachDevice to fit
for different libvirt drivers. For example, qemu driver prefers pci-stub, but
Xen prefers pciback.
Signed-off-by: Chunyan Liu <cyliu@suse.com>
When LXC labels USB devices during hotplug, it is running in
host context, so it needs to pass in a vroot path to the
container root.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Unmanaged PCI devices were only leaked if pciDeviceListAdd failed but
managed devices were always leaked. And leaking PCI device is likely to
leave PCI config file descriptor open. This patch fixes
qemuReattachPciDevice to either free the PCI device or add it to the
inactivePciHostdevs list.
Remove the obsolete 'qemud' naming prefix and underscore
based type name. Introduce virQEMUDriverPtr as the replacement,
in common with LXC driver naming style
The libvirt coding standard is to use 'function(...args...)'
instead of 'function (...args...)'. A non-trivial number of
places did not follow this rule and are fixed in this patch.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Save/restore with passed through USB devices currently only works if the
USB device can be found at the same USB address where it used to be
before saving a domain. This makes sense in case a user explicitly
configure the USB address in domain XML. However, if the device was
found automatically by vendor/product identification, we should try to
search for that device when restoring the domain and use any device we
find as long as there is only one available. In other words, the USB
device can now be removed and plugged again or the host can be rebooted
between saving and restoring the domain.
All USB device lookup functions emit an error when they cannot find the
requested device. With this patch, their caller can choose if a missing
device is an error or normal condition.
The code which looks up a USB device specified by hostdev is duplicated
in two places. This patch creates a dedicated function that can be
called in both places.
https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.
* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/; If/. If/
The underlying function to set the vlan tag of an SR-IOV network
device was already in place (although an extra patch to save/restore
the original vlan tag was needed), and recent patches added the
ability to configure a vlan tag. This patch just ties those two
together.
An SR-IOV device doesn't support vlan trunking, so if anyone tries to
configure more than a single tag, or set the trunk flag, and error is
logged.
Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)
You should have received a copy of the GNU General Public License
along with Foobar. If not, see <http://www.gnu.org/licenses/>.
This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').
Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:
src/security/security_selinux.h
src/security/security_driver.h
src/security/security_selinux.c
src/security/security_apparmor.h
src/security/security_apparmor.c
src/security/security_driver.c
Introduce new members in the virMacAddr 'class'
- virMacAddrSet: set virMacAddr from a virMacAddr
- virMacAddrSetRaw: setting virMacAddr from raw 6 byte MAC address buffer
- virMacAddrGetRaw: writing virMacAddr into raw 6 byte MAC address buffer
- virMacAddrCmp: comparing two virMacAddr
- virMacAddrCmpRaw: comparing a virMacAddr with a raw 6 byte MAC address buffer
then replace raw MAC addresses by replacing
- 'unsigned char *' with virMacAddrPtr
- 'unsigned char ... [VIR_MAC_BUFLEN]' with virMacAddr
and introduce usage of above functions where necessary.
One of our latest USB device handling patches
05abd1507d introduced a regression.
That is, we first create a temporary list of all USB devices that
are to be used by domain just starting up. Then we iterate over and
check if a device from the list is in the global list of currently
assigned devices (activeUsbHostdevs). If not, we add it there and
continue with next iteration then. But if a device from temporary
list is either taken already or adding to the activeUsbHostdevs fails,
we remove all devices in temp list from the activeUsbHostdevs list.
Therefore, if a device is already taken we remove it from
activeUsbHostdevs even if we should not. Thus, next time we allow
the device to be assigned to another domain.
src/qemu/qemu_hostdev.c:
refactor qemuPrepareHostdevUSBDevices function, make it focus on
adding usb device to activeUsbHostdevs after check. After that,
the usb hotplug function qemuDomainAttachHostDevice also could use
it.
expand qemuPrepareHostUSBDevices to perform the usb search,
rollback on failure.
src/qemu/qemu_hotplug.c:
If there are multiple usb devices available with same vendorID and productID,
but with different value of "bus, device", we give an error to let user
use <address> to specify the desired one.
usbFindDevice():get usb device according to
idVendor, idProduct, bus, device
it is the exact match of the four parameters
usbFindDeviceByBus():get usb device according to bus, device
it returns only one usb device same as usbFindDevice
usbFindDeviceByVendor():get usb device according to idVendor,idProduct
it probably returns multiple usb devices.
usbDeviceSearch(): a helper function to do the actual search
If the daemon is restarted it will lose list of active
USB devices assigned to active domains. Therefore we need
to rebuild this list on qemuProcessReconnect().
To prevent assigning one USB device to two domains,
we keep a list of assigned USB devices. On domain
startup - qemuProcessStart() - we insert devices
used by domain into the list but remove them only
on detach-device. Devices are, however, released
on qemuProcessStop() as well.
These changes are applied only if the hostdev has a parent net device
(i.e. if it was defined as "<interface type='hostdev'>" rather than
just "<hostdev>"). If the parent netdevice has virtual port
information, the original virtualport associate functions are called
(these set and restore both mac and port profile on an
interface). Otherwise, only mac address is set on the device.
Note that This is only supported for SR-IOV Virtual Functions (not for
standard PCI or USB netdevs), and virtualport association is only
supported for 802.1Qbh. For all other types of cards and types of
virtualport, a "Config Unsupported" error is returned and the
operation fails.
Signed-off-by: Roopa Prabhu <roprabhu@cisco.com>
pciTrySecondaryBusReset checks if there is active device on the
same bus, however, qemu driver doesn't maintain an effective
list for the inactive devices, and it passes meaningless argument
for parameter "inactiveDevs". e.g. (qemuPrepareHostdevPCIDevices)
if (!(pcidevs = qemuGetPciHostDeviceList(hostdevs, nhostdevs)))
return -1;
..skipped...
if (pciResetDevice(dev, driver->activePciHostdevs, pcidevs) < 0)
goto reattachdevs;
NB, the "pcidevs" used above are extracted from domain def, and
thus one won't be able to attach a device of which bus has other
device even detached from host (nodedev-detach). To see more
details of the problem:
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=773667
This patch is to resolve the problem by introducing an inactive
PCI device list (just like qemu_driver->activePciHostdevs), and
the whole logic is:
* Add the device to inactive list during nodedev-dettach
* Remove the device from inactive list during nodedev-reattach
* Remove the device from inactive list during attach-device
(for non-managed device)
* Add the device to inactive list after detach-device, only
if the device is not managed
With the above, we have a sufficient inactive PCI device list, and thus
we can use it for pciResetDevice. e.g.(qemuPrepareHostdevPCIDevices)
if (pciResetDevice(dev, driver->activePciHostdevs,
driver->inactivePciHostdevs) < 0)
goto reattachdevs;
* src/qemu/qemu_hostdev.c (qemuDomainReAttachHostdevDevices):
pciDeviceListFree(pcidevs) in the end free()s the device even if
it's in use by other domain, which can cause a race.
How to reproduce:
<script>
virsh nodedev-dettach pci_0000_00_19_0
virsh start test
virsh attach-device test hostdev.xml
virsh start test2
for i in {1..5}; do
echo "[ -- ${i}th time --]"
virsh nodedev-reattach pci_0000_00_19_0
done
echo "clean up"
virsh destroy test
virsh nodedev-reattach pci_0000_00_19_0
</script>
Device pci_0000_00_19_0 dettached
Domain test started
Device attached successfully
error: Failed to start domain test2
error: Requested operation is not valid: PCI device 0000:00:19.0 is in use by domain test
[ -- 1th time --]
Device pci_0000_00_19_0 re-attached
[ -- 2th time --]
Device pci_0000_00_19_0 re-attached
[ -- 3th time --]
Device pci_0000_00_19_0 re-attached
[ -- 4th time --]
Device pci_0000_00_19_0 re-attached
[ -- 5th time --]
Device pci_0000_00_19_0 re-attached
clean up
Domain test destroyed
Device pci_0000_00_19_0 re-attached
The patch also fixes another problem, there won't be error like
"qemuDomainReAttachHostdevDevices: Not reattaching active
device 0000:00:19.0" in daemon log if some device is in active.
As pciResetDevice and pciReattachDevice won't be called for
the device anymore. This is sensible as we already reported
error when preparing the device if it's active. Blindly trying
to pciResetDevice & pciReattachDevice on the device and getting
an error is just redundant.
To support "managed" mode of host PCI device, we record the original
states (unbind_from_stub, remove_slot, and reprobe) so that could
reattach the device to host with original driver. But there is no XML
for theses attrs, and thus after daemon is restarted, we lose the
original states. It's easy to reproduce:
1) virsh start domain
2) virsh attach-device dom hostpci.xml (in 'managed' mode)
3) service libvirtd restart
4) virsh destroy domain
You will see the device won't be bound to the original driver
if there was one.
This patch is to solve the problem by introducing internal XML
(won't be dumped to user, only dumped to status XML). The XML is:
<origstates>
<unbind/>
<remove_slot/>
<reprobe/>
</origstates>
Which will be child node of <hostdev><source>...</souce></hostdev>.
(only for PCI device).
A new struct "virDomainHostdevOrigStates" is introduced for the XML,
and the according members are updated when preparing the PCI device.
And function "qemuUpdateActivePciHostdevs" is modified to honor
the original states. Use of qemuGetPciHostDeviceList is removed
in function "qemuUpdateActivePciHostdevs", and the "managed" value of
the device config is honored by the change. This fixes another problem
alongside:
qemuGetPciHostDeviceList set the device as "managed" force
regardless of whether the device is configured as "managed='yes'"
or not in XML, which is not right.
BZ# https://bugzilla.redhat.com/show_bug.cgi?id=736214
The problem is caused by the original info of domain's PCI dev is
maintained by qemu_driver->activePciHostdevs list, (E.g. dev->reprobe,
which stands for whether need to reprobe driver for the dev when do
reattachment). The fields (dev->reprobe, dev->unbind_from_stub, and
dev->remove_slot) are initialized properly when preparing the PCI
device for managed attachment. However, when do reattachment, it
construct a complete new "pciDevice" without honoring the original
dev info, and thus the dev won't get the original driver or can get
other problem.
This patch is to fix the problem by get the devs from list
driver->activePciHostdevs.
Tested with following 3 scenarios:
* the PCI was bound to some driver not pci-stub before attaching
result: the device will be bound to the original driver
* the PCI was bound to pci-stub before attaching
result: no driver reprobing, and still bound to pci-stub
* The PCI was not bound to any driver
result: no driver reprobing, and still not bound to any driver.
When failing on starting a domain, it tries to reattach all the PCI
devices defined in the domain conf, regardless of whether the devices
are still used by other domain. This will cause the devices to be deleted
from the list qemu_driver->activePciHostdevs, thus the devices will be
thought as usable even if it's not true. And following commands
nodedev-{reattach,reset} will be successful.
How to reproduce:
1) Define two domains with same PCI device defined in the confs.
2) # virsh start domain1
3) # virsh start domain2
4) # virsh nodedev-reattach $pci_device
You will see the device will be reattached to host successfully.
As pciDeviceReattach just check if the device is still used by
other domain via checking if the device is in list driver->activePciHostdevs,
however, the device is deleted from the list by step 2).
This patch is to prohibit the bug by:
1) Prohibit a domain starting or device attachment right at
preparation period (qemuPrepareHostdevPCIDevices) if the
device is in list driver->activePciHostdevs, which means
it's used by other domain.
2) Introduces a new field for struct _pciDevice, (const char *used_by),
it will be set as the domain name at preparation period,
(qemuPrepareHostdevPCIDevices). Thus we can prohibit deleting
the device from driver->activePciHostdevs if it's still used by
other domain when stopping the domain process.
* src/pci.h (define two internal functions, pciDeviceSetUsedBy and
pciDevceGetUsedBy)
* src/pci.c (new field "const char *used_by" for struct _pciDevice,
implementations for the two new functions)
* src/libvirt_private.syms (Add the two new internal functions)
* src/qemu_hostdev.h (Modify the definition of functions
qemuPrepareHostdevPCIDevices, and qemuDomainReAttachHostdevDevices)
* src/qemu_hostdev.c (Prohibit preparation and don't delete the
device from activePciHostdevs list if it's still used by other domain)
* src/qemu_hotplug.c (Update function usage, as the definitions are
changed)
Signed-off-by: Eric Blake <eblake@redhat.com>
pciDeviceListSteal(pcidevs, dev) removes dev from pcidevs reducing
the length of pcidevs, so moving onto what was the next dev is wrong.
Instead callers should pop entry 0 repeatedly until pcidevs is empty.
Signed-off-by: Steve Hodgson <shodgson@solarflare.com>
Signed-off-by: Shradha Shah <sshah@solarflare.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
The QEMU driver file is far too large. Move all the hostdev
helper code out into a separate file. No functional change.
* src/qemu/qemu_hostdev.c, src/qemu/qemu_hostdev.h,
src/Makefile.am: Add hostdev helper file
* src/qemu/qemu_driver.c: Delete hostdev code
