Commit Graph

654 Commits

Author SHA1 Message Date
Michal Privoznik
4da534c0b9 qemu: Enforce qemuSecurity wrappers
Now that we have some qemuSecurity wrappers over
virSecurityManager APIs, lets make sure everybody sticks with
them. We have them for a reason and calling virSecurityManager
API directly instead of wrapper may lead into accidentally
labelling a file on the host instead of namespace.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-03-06 08:54:28 +01:00
Marc Hartmayer
e22de286b1 qemu: Fix deadlock across fork() in QEMU driver
The functions in virCommand() after fork() must be careful with regard
to accessing any mutexes that may have been locked by other threads in
the parent process. It is possible that another thread in the parent
process holds the lock for the virQEMUDriver while fork() is called.
This leads to a deadlock in the child process when
'virQEMUDriverGetConfig(driver)' is called and therefore the handshake
never completes between the child and the parent process. Ultimately
the virDomainObjectPtr will never be unlocked.

It gets much worse if the other thread of the parent process, that
holds the lock for the virQEMUDriver, tries to lock the already locked
virDomainObject. This leads to a completely unresponsive libvirtd.

It's possible to reproduce this case with calling 'virsh start XXX'
and 'virsh managedsave XXX' in a tight loop for multiple domains.

This commit fixes the deadlock in the same way as it is described in
commit 61b52d2e38.

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
2017-02-21 15:47:32 +01:00
Michal Privoznik
5c74cf1f44 qemu: Allow @rendernode for virgl domains
When enabling virgl, qemu opens /dev/dri/render*. So far, we are
not allowing that in devices CGroup nor creating the file in
domain's namespace and thus requiring users to set the paths in
qemu.conf. This, however, is suboptimal as it allows access to
ALL qemu processes even those which don't have virgl configured.
Now that we have a way to specify render node that qemu will use
we can be more cautious and enable just that.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-20 10:44:22 +01:00
Michal Privoznik
1bb787fdc9 qemuDomainGetHostdevPath: Report /dev/vfio/vfio less frequently
So far, qemuDomainGetHostdevPath has no knowledge of the reasong
it is called and thus reports /dev/vfio/vfio for every VFIO
backed device. This is suboptimal, as we want it to:

a) report /dev/vfio/vfio on every addition or domain startup
b) report /dev/vfio/vfio only on last VFIO device being unplugged

If a domain is being stopped then namespace and CGroup die with
it so no need to worry about that. I mean, even when a domain
that's exiting has more than one VFIO devices assigned to it,
this function does not clean /dev/vfio/vfio in CGroup nor in the
namespace. But that doesn't matter.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-02-20 07:21:59 +01:00
Michal Privoznik
b8e659aa98 qemuDomainGetHostdevPath: Create /dev/vfio/vfio iff needed
So far, we are allowing /dev/vfio/vfio in the devices cgroup
unconditionally (and creating it in the namespace too). Even if
domain has no hostdev assignment configured. This is potential
security hole. Therefore, when starting the domain (or
hotplugging a hostdev) create & allow /dev/vfio/vfio too (if
needed).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-02-20 07:21:58 +01:00
Michal Privoznik
9d92f533f8 qemuSetupHostdevCgroup: Use qemuDomainGetHostdevPath
Since these two functions are nearly identical (with
qemuSetupHostdevCgroup actually calling virCgroupAllowDevicePath)
we can have one function call the other and thus de-duplicate
some code.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
2017-02-20 07:21:58 +01:00
Michal Privoznik
b57bd206b9 qemu_conf: Check for namespaces availability more wisely
The bare fact that mnt namespace is available is not enough for
us to allow/enable qemu namespaces feature. There are other
requirements: we must copy all the ACL & SELinux labels otherwise
we might grant access that is administratively forbidden or vice
versa.
At the same time, the check for namespace prerequisites is moved
from domain startup time to qemu.conf parser as it doesn't make
much sense to allow users to start misconfigured libvirt just to
find out they can't start a single domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-15 12:43:23 +01:00
Andrea Bolognani
ee6ec7824d qemu: Call chmod() after mknod()
mknod() is affected my the current umask, so we're not
guaranteed the newly-created device node will have the
right permissions.

Call chmod(), which is not affected by the current umask,
immediately afterwards to solve the issue.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1421036
2017-02-14 19:23:05 +01:00
Ján Tomko
723fef99c0 qemu: enforce maximum ports value for nec-xhci
This controller only allows up to 15 ports.

https://bugzilla.redhat.com/show_bug.cgi?id=1375417
2017-02-13 16:34:09 +01:00
Michal Privoznik
c2130c0d47 qemu_security: Introduce ImageLabel APIs
Just like we need wrappers over other virSecurityManager APIs, we
need one for virSecurityManagerSetImageLabel and
virSecurityManagerRestoreImageLabel. Otherwise we might end up
relabelling device in wrong namespace.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-09 08:04:57 +01:00
Michal Privoznik
b7feabbfdc qemuDomainNamespaceSetupDisk: Simplify disk check
Firstly, instead of checking for next->path the
virStorageSourceIsEmpty() function should be used which also
takes disk type into account.
Secondly, not every disk source passed has the correct type set
(due to our laziness). Therefore, instead of checking for
virStorageSourceIsBlockLocal() and also S_ISBLK() the former can
be refined to just virStorageSourceIsLocalStorage().

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-08 15:56:21 +01:00
Michal Privoznik
786d8d91b4 qemuDomainDiskChainElement{Prepare,Revoke}: manage /dev entry
Again, one missed bit. This time without this commit there is no
/dev entry  in the namespace of the qemu process when doing disk
snapshots or block-copy.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-08 15:56:13 +01:00
Michal Privoznik
18ce9d139d qemuDomainNamespace{Setup,Teardown}Disk: Don't pass pointer to full disk
These functions do not need to see the whole virDomainDiskDef.
Moreover, they are going to be called from places where we don't
have access to the full disk definition. Sticking with
virStorageSource is more than enough.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-08 15:56:05 +01:00
Michal Privoznik
76d491ef14 qemuDomainNamespaceSetupDisk: Drop useless @src variable
Since its introduction in 81df21507b this variable was never
used.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-08 15:55:56 +01:00
Michal Privoznik
8dc867e978 qemu_domain: Don't pass virDomainDeviceDefPtr to ns helpers
There is no need for this. None of the namespace helpers uses it.
Historically it was used when calling secdriver APIs, but we
don't to that anymore.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-08 15:55:52 +01:00
Andrea Bolognani
c2e60ad0e5 qemu: Forbid <memoryBacking><locked> without <memtune><hard_limit>
In order for memory locking to work, the hard limit on memory
locking (and usage) has to be set appropriately by the user.

The documentation mentions the requirement already: with this
patch, it's going to be enforced by runtime checks as well,
by forbidding a non-compliant guest from being defined as well
as edited and started.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1316774
2017-02-07 18:43:10 +01:00
Michal Privoznik
7f0b382522 qemuDomainAttachDeviceMknod: Don't loop endlessly
When working with symlinks it is fairly easy to get into a loop.
Don't.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-07 13:20:19 +01:00
Michal Privoznik
3f5fcacf89 qemuDomainAttachDeviceMknod: Deal with symlinks
Similarly to one of the previous commits, we need to deal
properly with symlinks in hotplug case too.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-07 13:20:17 +01:00
Michal Privoznik
4ac847f93b qemuDomainCreateDevice: Don't loop endlessly
When working with symlinks it is fairly easy to get into a loop.
Don't.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-07 13:18:32 +01:00
Michal Privoznik
54ed672214 qemuDomainCreateDevice: Properly deal with symlinks
Imagine you have a disk with the following source set up:

/dev/disk/by-uuid/$uuid (symlink to) -> /dev/sda

After cbc45525cb the transitive end of the symlink chain is
created (/dev/sda), but we need to create any item in chain too.
Others might rely on that.
In this case, /dev/disk/by-uuid/$uuid comes from domain XML thus
it is this path that secdriver tries to relabel. Not the resolved
one.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-07 13:18:10 +01:00
Michal Privoznik
b621291f5c qemuDomain{Attach,Detach}Device NS helpers: Don't relabel devices
After previous commit this has become redundant step.
Also setting up devices in namespace and setting their label
later on are two different steps and should be not done at once.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-02-07 10:40:53 +01:00
Michal Privoznik
572eda12ad qemu: Implement mtu on interface
Not only we should set the MTU on the host end of the device but
also let qemu know what MTU did we set.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-26 10:00:01 +01:00
Michal Privoznik
b020cf73fe domain_conf: Introduce <mtu/> to <interface/>
So far we allow to set MTU for libvirt networks. However, not all
domain interfaces have to be plugged into a libvirt network and
even if they are, they might want to have a different MTU (e.g.
for testing purposes).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-26 09:59:56 +01:00
Chen Hanxiao
980f2a35c7 qemu_domain: add timestamp in tainting of guests log
We lacked of timestamp in tainting of guests log,
which bring troubles for finding guest issues:
such as whether a guest powerdown caused by qemu-monitor-command
or others issues inside guests.
If we had timestamp in tainting of guests log,
it would be helpful when checking guest's /var/log/messages.

Signed-off-by: Chen Hanxiao <chenhanxiao@gmail.com>
2017-01-21 12:34:19 -05:00
Michal Privoznik
57b5e27d3d qemu: set default vhost-user ifname
Based on work of Mehdi Abaakouk <sileht@sileht.net>.

When parsing vhost-user interface XML and no ifname is found we
can try to fill it in in post parse callback. The way this works
is we try to make up interface name from given socket path and
then ask openvswitch whether it knows the interface.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-20 15:42:12 +01:00
Michal Privoznik
d0baf54e53 qemu: Actually unshare() iff running as root
https://bugzilla.redhat.com/show_bug.cgi?id=1413922

While all the code that deals with qemu namespaces correctly
detects whether we are running as root (and turn into NO-OP for
qemu:///session) the actual unshare() call is not guarded with
such check. Therefore any attempt to start a domain under
qemu:///session shall fail as unshare() is reserved for root.

The fix consists of moving unshare() call (for which we have a
wrapper called virProcessSetupPrivateMountNS) into
qemuDomainBuildNamespace() where the proper check is performed.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
2017-01-17 13:23:56 +01:00
Michal Privoznik
93a062c3b2 qemu: Copy SELinux labels for namespace too
When creating new /dev/* for qemu, we do chown() and copy ACLs to
create the exact copy from the original /dev. I though that
copying SELinux labels is not necessary as SELinux will chose the
sane defaults. Surprisingly, it does not leaving namespace with
the following labels:

crw-rw-rw-. root root system_u:object_r:tmpfs_t:s0     random
crw-------. root root system_u:object_r:tmpfs_t:s0     rtc0
drwxrwxrwt. root root system_u:object_r:tmpfs_t:s0     shm
crw-rw-rw-. root root system_u:object_r:tmpfs_t:s0     urandom

As a result, domain is unable to start:

error: internal error: process exited while connecting to monitor: Error in GnuTLS initialization: Failed to acquire random data.
qemu-kvm: cannot initialize crypto: Unable to initialize GNUTLS library: Failed to acquire random data.

The solution is to copy the SELinux labels as well.

Reported-by: Andrea Bolognani <abologna@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-13 14:45:52 +01:00
Michal Privoznik
cbc45525cb qemuDomainCreateDevice: Canonicalize paths
So far the decision whether /dev/* entry is created in the qemu
namespace is really simple: does the path starts with "/dev/"?
This can be easily fooled by providing path like the following
(for any considered device like disk, rng, chardev, ..):

  /dev/../var/lib/libvirt/images/disk.qcow2

Therefore, before making the decision the path should be
canonicalized.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-11 18:08:13 +01:00
Michal Privoznik
49f326edc0 qemu: Use namespaces iff available on the host kernel
So far the namespaces were turned on by default unconditionally.
For all non-Linux platforms we provided stub functions that just
ignored whatever namespaces setting there was in qemu.conf and
returned 0 to indicate success. Moreover, we didn't really check
if namespaces are available on the host kernel.

This is suboptimal as we might have ignored user setting.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-11 18:07:43 +01:00
Michal Privoznik
41816751a7 util: Introduce virFileMoveMount
This is a simple wrapper over mount(). However, not every system
out there is capable of moving a mount point. Therefore, instead
of having to deal with this fact in all the places of our code we
can have a simple wrapper and deal with this fact at just one
place.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-11 18:06:30 +01:00
Michal Privoznik
2ff8c30548 qemuDomainSetupAllInputs: Update debug message
Due to a copy-paste error, the debug message reads:

  Setting up disks

It should have been:

  Setting up inputs.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-11 17:39:24 +01:00
Michal Privoznik
269589146c qemu_domain: Move qemuDomainGetPreservedMounts
This function is used only from code compiled on Linux. Therefore
on non-Linux platforms it triggers compilation error:

../../src/qemu/qemu_domain.c:209:1: error: unused function 'qemuDomainGetPreservedMounts' [-Werror,-Wunused-function]

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-10 19:23:49 +01:00
Michal Privoznik
406e390962 qemu: Drop qemuDomainDeleteNamespace
After previous commits, this function is no longer needed.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-10 13:04:57 +01:00
Michal Privoznik
5d198c2b2c qemuDomainCreateNamespace: move mkdir to qemuDomainBuildNamespace
Again, there is no need to create /var/lib/libvirt/$domain.*
directories in CreateNamespace(). It is sufficient to create them
as soon as we need them which is in BuildNamespace. This way we
don't leave them around for the whole lifetime of domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-10 13:04:57 +01:00
Michal Privoznik
5d30057695 qemuDomainGetPreservedMounts: Do not special case /dev
The c1140eb9e got me thinking. We don't want to special case /dev
in qemuDomainGetPreservedMounts(), but in all other places in the
code we special case it anyway. I mean,
/var/run/libvirt/$domain.dev path is constructed separately just
so that it is not constructed here. It makes only a little sense
(if any at all).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-10 13:04:57 +01:00
Michal Privoznik
40ebbf72d5 qemuDomainCreateNamespace: s/unlink/rmdir/
If something goes wrong in this function we try a rollback. That
is unlink all the directories we created earlier. For some weird
reason unlink() was called instead of rmdir().

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-10 13:04:57 +01:00
Martin Kletzander
c1140eb9ed qemu: Remove /dev mount info properly
Just so it doesn't bite us in the future, even though it's unlikely.

And fix the comment above it as well.  Commit e08ee7cd34 took the
info from the function it's calling, but that was lie itself in the
first place.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2017-01-05 16:24:55 +01:00
Michal Privoznik
e08ee7cd34 qemuDomainGetPreservedMounts: Fetch list of /dev/* mounts dynamically
With my namespace patches, we are spawning qemu in its own
namespace so that we can manage /dev entries ourselves. However,
some filesystems mounted under /dev needs to be preserved in
order to be shared with the parent namespace (e.g. /dev/pts).
Currently, the list of mount points to preserve is hardcoded
which ain't right - on some systems there might be less or more
items under real /dev that on our list. The solution is to parse
/proc/mounts and fetch the list from there.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-05 16:00:20 +01:00
Michal Privoznik
dd78da09b0 qemuDomainCreateDevice: Be more careful about device path
Again, not something that I'd hit, but there is a chance in
theory that this might bite us. Currently the way we decide
whether or not to create /dev entry for a device is by marching
first four characters of path with "/dev". This might be not
enough. Just imagine somebody has a disk image stored under
"/devil/path/to/disk". We ought to be matching against "/dev/".

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-04 15:36:42 +01:00
Michal Privoznik
ce01a2b11c qemuDomainAttachDeviceMknodHelper: Don't unlink() so often
Not that I'd encounter any bug here, but the code doesn't look
100% correct. Imagine, somebody is trying to attach a device to a
domain, and the device's /dev entry already exists in the qemu
namespace. This is handled gracefully and the control continues
with setting up ACLs and calling security manager to set up
labels. Now, if any of these steps fail, control jump on the
'cleanup' label and unlink() the file straight away. Even when it
was not us who created the file in the first place. This can be
possibly dangerous.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-04 15:36:42 +01:00
Michal Privoznik
3aae99fe71 qemu: Handle EEXIST gracefully in qemuDomainCreateDevice
https://bugzilla.redhat.com/show_bug.cgi?id=1406837

Imagine you have a domain configured in such way that you are
assigning two PCI devices that fall into the same IOMMU group.
With mount namespace enabled what happens is that for the first
PCI device corresponding /dev/vfio/X entry is created and when
the code tries to do the same for the second mknod() fails as
/dev/vfio/X already exists:

2016-12-21 14:40:45.648+0000: 24681: error :
qemuProcessReportLogError:1792 : internal error: Process exited
prior to exec: libvirt: QEMU Driver error : Failed to make device
/var/run/libvirt/qemu/windoze.dev//vfio/22: File exists

Worse, by default there are some devices that are created in the
namespace regardless of domain configuration (e.g. /dev/null,
/dev/urandom, etc.). If one of them is set as backend for some
guest device (e.g. rng, chardev, etc.) it's the same story as
described above.

Weirdly, in attach code this is already handled.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2017-01-04 15:36:42 +01:00
John Ferlan
7f7d990483 qemu: Don't assume secret provided for LUKS encryption
https://bugzilla.redhat.com/show_bug.cgi?id=1405269

If a secret was not provided for what was determined to be a LUKS
encrypted disk (during virStorageFileGetMetadata processing when
called from qemuDomainDetermineDiskChain as a result of hotplug
attach qemuDomainAttachDeviceDiskLive), then do not attempt to
look it up (avoiding a libvirtd crash) and do not alter the format
to "luks" when adding the disk; otherwise, the device_add would
fail with a message such as:

   "unable to execute QEMU command 'device_add': Property 'scsi-hd.drive'
    can't find value 'drive-scsi0-0-0-0'"

because of assumptions that when the format=luks that libvirt would have
provided the secret to decrypt the volume.

Access to unlock the volume will thus be left to the application.
2017-01-03 12:59:18 -05:00
Marc Hartmayer
fb2cd32c9a qemu: qemuDomainDiskChangeSupported: Add missing 'address' check
Disk->info is not live updatable so add a check for this. Otherwise
libvirt reports success even though no data was updated.

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
2016-12-20 11:22:44 +01:00
Michal Privoznik
ab41ce7f4e qemu: Mark more namespace code linux-only
Some of the functions are not called on non-linux platforms
which makes them useless there.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-16 11:51:06 +00:00
Michal Privoznik
f444faa94a qemu: Enable mount namespace
https://bugzilla.redhat.com/show_bug.cgi?id=1404952

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
661887f558 qemu: Let users opt-out from containerization
Given how intrusive previous patches are, it might happen that
there's a bug or imperfection. Lets give users a way out: if they
set 'namespaces' to an empty array in qemu.conf the feature is
suppressed.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
f95c5c48d4 qemu: Manage /dev entry on RNG hotplug
When attaching a device to a domain that's using separate mount
namespace we must maintain /dev entries in order for qemu process
to see them.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
f5fdf23a68 qemu: Manage /dev entry on chardev hotplug
When attaching a device to a domain that's using separate mount
namespace we must maintain /dev entries in order for qemu process
to see them.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
6e57492839 qemu: Manage /dev entry on hostdev hotplug
When attaching a device to a domain that's using separate mount
namespace we must maintain /dev entries in order for qemu process
to see them.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
81df21507b qemu: Manage /dev entry on disk hotplug
When attaching a device to a domain that's using separate mount
namespace we must maintain /dev entries in order for qemu process
to see them.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
2160f338a7 qemu: Prepare RNGs when starting a domain
When starting a domain and separate mount namespace is used, we
have to create all the /dev entries that are configured for the
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
8ec8a8c5ff qemu: Prepare inputs when starting a domain
When starting a domain and separate mount namespace is used, we
have to create all the /dev entries that are configured for the
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
2c654490f3 qemu: Prepare TPM when starting a domain
When starting a domain and separate mount namespace is used, we
have to create all the /dev entries that are configured for the
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
4e4451019c qemu: Prepare chardevs when starting a domain
When starting a domain and separate mount namespace is used, we
have to create all the /dev entries that are configured for the
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
73267cec46 qemu: Prepare hostdevs when starting a domain
When starting a domain and separate mount namespace is used, we
have to create all the /dev entries that are configured for the
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
054202d020 qemu: Prepare disks when starting a domain
When starting a domain and separate mount namespace is used, we
have to create all the /dev entries that are configured for the
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
bb4e529664 qemu: Spawn qemu under mount namespace
Prime time. When it comes to spawning qemu process and
relabelling all the devices it's going to touch, there's inherent
race with other applications in the system (e.g. udev). Instead
of trying convincing udev to not touch libvirt managed devices,
we can create a separate mount namespace for the qemu, and mount
our own /dev there. Of course this puts more work onto us as we
have to maintain /dev files on each domain start and device
hot(un-)plug. On the other hand, this enhances security also.

From technical POV, on domain startup process the parent
(libvirtd) creates:

  /var/lib/libvirt/qemu/$domain.dev
  /var/lib/libvirt/qemu/$domain.devpts

The child (which is going to be qemu eventually) calls unshare()
to create new mount namespace. From now on anything that child
does is invisible to the parent. Child then mounts tmpfs on
$domain.dev (so that it still sees original /dev from the host)
and creates some devices (as explained in one of the previous
patches). The devices have to be created exactly as they are in
the host (including perms, seclabels, ACLs, ...). After that it
moves $domain.dev mount to /dev.

What's the $domain.devpts mount there for then you ask? QEMU can
create PTYs for some chardevs. And historically we exposed the
host ends in our domain XML allowing users to connect to them.
Therefore we must preserve devpts mount to be shared with the
host's one.

To make this patch as small as possible, creating of devices
configured for domain in question is implemented in next patches.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-15 09:25:16 +01:00
Michal Privoznik
7ed6934f3b virDomainObjGetShortName: take virDomainDef
So far this function takes virDomainObjPtr which:
1) is an overkill,
2) might be not available in all the places we will use it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-12-08 15:45:52 +01:00
Laine Stump
9b0848d523 qemu: propagate virQEMUDriver object to qemuDomainDeviceCalculatePCIConnectFlags
If libvirtd is running unprivileged, it can open a device's PCI config
data in sysfs, but can only read the first 64 bytes. But as part of
determining whether a device is Express or legacy PCI,
qemuDomainDeviceCalculatePCIConnectFlags() will be updated in a future
patch to call virPCIDeviceIsPCIExpress(), which tries to read beyond
the first 64 bytes of the PCI config data and fails with an error log
if the read is unsuccessful.

In order to avoid creating a parallel "quiet" version of
virPCIDeviceIsPCIExpress(), this patch passes a virQEMUDriverPtr down
through all the call chains that initialize the
qemuDomainFillDevicePCIConnectFlagsIterData, and saves the driver
pointer with the rest of the iterdata so that it can be used by
qemuDomainDeviceCalculatePCIConnectFlags(). This pointer isn't used
yet, but will be used in an upcoming patch (that detects Express vs
legacy PCI for VFIO assigned devices) to examine driver->privileged.
2016-11-30 15:28:07 -05:00
Michal Privoznik
c2a5a4e7ea virstring: Unify string list function names
We have couple of functions that operate over NULL terminated
lits of strings. However, our naming sucks:

virStringJoin
virStringFreeList
virStringFreeListCount
virStringArrayHasString
virStringGetFirstWithPrefix

We can do better:

virStringListJoin
virStringListFree
virStringListFreeCount
virStringListHasString
virStringListGetFirstWithPrefix

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-11-25 13:54:05 +01:00
Nikolay Shirokovskiy
aaf2992d90 qemu: agent: fix unsafe agent access
qemuDomainObjExitAgent is unsafe.

First it accesses domain object without domain lock.
Second it uses outdated logic that goes back to commit 79533da1 of
year 2009 when code was quite different. (unref function
instead of unreferencing only unlocked and disposed object
in case of last reference and leaved unlocking to the caller otherwise).
Nowadays this logic may lead to disposing locked object
i guess.

Another problem is that the callers of qemuDomainObjEnterAgent
use domain object again (namely priv->agent) without domain lock.

This patch address these two problems.

qemuDomainGetAgent is dropped as unused.
2016-11-23 11:31:28 +03:00
Nikolay Shirokovskiy
3c1c56781d qemu: drop write-only agentStart 2016-11-23 11:31:14 +03:00
Marc Hartmayer
1c122e737e Refactoring: Use virHostdevIsSCSIDevice()
Use the util function virHostdevIsSCSIDevice() to simplify if
statements.

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
2016-11-22 14:37:36 +01:00
Marc Hartmayer
505bc9b025 qemu: Fix improper union member access on hostdevs
Add missing checks if a hostdev is a subsystem/SCSI device before access
the union member 'subsys'/'scsi'.  Also fix indentation and simplify
qemuDomainObjCheckHostdevTaint().

Signed-off-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
2016-11-22 14:37:36 +01:00
Peter Krempa
0df2524acb qemu: domain: Refresh vcpu halted state using qemuMonitorGetCpuHalted
Don't use qemuMonitorGetCPUInfo which does a lot of matching to get the
full picture which is not necessary and would be mostly discarded.

Refresh only the vcpu halted state using data from query-cpus.
2016-11-21 17:19:48 +01:00
Peter Krempa
3f71c79768 qemu: monitor: Extract qemu cpu id along with other data
Storing of the ID will allow simpler extraction of data present only in
query-cpus without the need to call qemuMonitorGetCPUInfo in statistics
paths.
2016-11-21 17:19:48 +01:00
Laine Stump
d8bd837669 qemu: add a USB3 controller to Q35 domains by default
Previously we added a set of EHCI+UHCI controllers to Q35 machines to
mimic real hardware as closely as possible, but recent discussions
have pointed out that the nec-usb-xhci (USB3) controller is much more
virtualization-friendly (uses less CPU), so this patch switches the
default for Q35 machinetypes to add an XHCI instead (if it's
supported, which it of course *will* be).

Since none of the existing test cases left out USB controllers in the
input XML, a new Q35 test case was added which has *no* devices, so
ends up with only the defaults always put in by qemu, plus those added
by libvirt.
2016-11-14 14:22:23 -05:00
Laine Stump
807232203a qemu: don't force-add a dmi-to-pci-bridge just on principle
Now the a dmi-to-pci-bridge is automatically added just as it's needed
(when a pci-bridge is being added), we no longer have any need to
force-add one to every single Q35 domain.
2016-11-14 14:21:43 -05:00
Laine Stump
50adb8a660 qemu: new functions qemuDomainMachineHasPCI[e]Root()
These functions provide a simple one line method of learning if the
current domain has a pci-root or pcie-root bus.
2016-11-14 14:03:09 -05:00
Martin Kletzander
acf0ec024a qemu: Save various defaults for shmem
We're keeping some things at default and that's not something we want to
do intentionally.  Let's save some sensible defaults upfront in order to
avoid having problems later.  The details for the defaults (of the newer
implementation) can be found in qemu's commit 5400c02b90bb:

  http://git.qemu.org/?p=qemu.git;a=commit;h=5400c02b90bb

Since we are merely saving the defaults it will not change the guest ABI
and thanks to the fact that we're doing it in the PostParse callback it
will not break the ABI stability checks.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2016-11-02 16:05:39 +01:00
John Ferlan
daf5c651f0 qemu: Add a secret object to/for a char source dev
Add the secret object so the 'passwordid=' can be added if the command line
if there's a secret defined in/on the host for TCP chardev TLS objects.

Preparation for the secret involves adding the secinfo to the char source
device prior to command line processing. There are multiple possibilities
for TCP chardev source backend usage.

Add test for at least a serial chardev as an example.
2016-10-26 07:18:25 -04:00
Viktor Mihajlovski
08f22976b1 qemu: Add domain support for VCPU halted state
Adding a field to the domain's private vcpu object to hold the halted
state information.
Adding two functions in support of the halted state:
- qemuDomainGetVcpuHalted: retrieve the halted state from a
  private vcpu object
- qemuDomainRefreshVcpuHalted: obtain the per-vcpu halted states
  via qemu monitor and store the results in the private vcpu objects

Signed-off-by: Viktor Mihajlovski <mihajlov@linux.vnet.ibm.com>
Reviewed-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Reviewed-by: Hao QingFeng <haoqf@linux.vnet.ibm.com>
Signed-off-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
2016-10-24 18:52:36 -04:00
Pavel Hrdina
7c8df1e82f domain: fix migration to older libvirt
Since TLS was introduced hostwide for libvirt 2.3.0 and a domain
configurable haveTLS was implemented for libvirt 2.4.0, we have to
modify the migratable XML for specific case where the 'tls' attribute
is based on setting from qemu.conf.

The "tlsFromConfig" is libvirt internal attribute and is stored only in
status XML to ensure that when libvirtd is restarted this internal flag
is not lost by the restart.

That flag is used to decide whether we should put *tls* attribute to
migratable XML or not.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2016-10-24 16:29:26 +02:00
Pavel Hrdina
0298531b29 domain: Add optional 'tls' attribute for TCP chardev
Add an optional "tls='yes|no'" attribute for a TCP chardev.

For QEMU, this will allow for disabling the host config setting of the
'chardev_tls' for a domain chardev channel by setting the value to "no" or
to attempt to use a host TLS environment when setting the value to "yes"
when the host config 'chardev_tls' setting is disabled, but a TLS environment
is configured via either the host config 'chardev_tls_x509_cert_dir' or
'default_tls_x509_cert_dir'

Signed-off-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2016-10-24 16:05:33 +02:00
John Ferlan
7bd8312e7f conf: Move the privateData from virDomainChrDef to virDomainChrSourceDef
Commit id '5f2a132786' should have placed the data in the host source
def structure since that's also used by smartcard, redirdev, and rng in
order to provide a backend tcp channel.  The data in the private structure
will be necessary in order to provide the secret properly.

This also renames the previous names from "Chardev" to "ChrSource" for
the private data structures and API's
2016-10-21 16:42:59 -04:00
John Ferlan
77a12987a4 Introduce virDomainChrSourceDefNew for virDomainChrDefPtr
Change the virDomainChrDef to use a pointer to 'source' and allocate
that pointer during virDomainChrDefNew.

This has tremendous "fallout" in the rest of the code which mainly
has to change source.$field to source->$field.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2016-10-21 14:03:36 -04:00
John Ferlan
5f2a132786 qemu: Introduce qemuDomainChardevPrivatePtr
Modeled after the qemuDomainHostdevPrivatePtr (commit id '27726d8c'),
create a privateData pointer in the _virDomainChardevDef to allow storage
of private data for a hypervisor in order to at least temporarily store
secret data for usage during qemuBuildCommandLine.

NB: Since the qemu_parse_command (qemuParseCommandLine) code is not
expecting to restore the secret data, there's no need to add code
code to handle this new structure there.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2016-10-19 15:40:29 -04:00
John Ferlan
6262a9b282 qemu: Remove unnecessary NULL arg check
qemuDomainSecret{Disk|Hostdev}Prepare has a prototype that checks for
ATTRIBUTE_NONNULL(1) for 'conn'.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2016-10-17 15:38:32 -04:00
Pavel Hrdina
fb8f3b1c22 qemu_command: add support to use virtio as secondary video device
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1369633

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2016-10-12 17:46:48 +02:00
Pavel Hrdina
4c029e8cfa qemu_command: properly detect which model to use for video device
This improves commit 706b5b6277 in a way that we check qemu capabilities
instead of what architecture we are running on to detect whether we can
use *virtio-vga* model or not.  This is not a case only for arm/aarch64.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2016-10-12 17:46:48 +02:00
Pavel Hrdina
133fb1401f qemu_domain: move video validation out of qemu_command
All definition validation that doesn't depend on qemu capabilities
and was allowed previously as valid definition should be placed into
qemuDomainDefValidate.

The check whether video type is supported or not was based on an enum
that translates type into model.  Use switch to ensure that if new
video type is added, it will be properly handled.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
2016-10-12 17:46:47 +02:00
Peter Krempa
043ba4a40a qemu: Reuse virDomainDeGetVcpusTopology to calculate total vcpu count
Rather than multiplying sockets, cores, and threads use the new helper
for getting the vcpu count resulting from the topology.
2016-10-11 13:52:09 +02:00
Michal Privoznik
8cfdd6e4f5 Revert "conf: Skip post parse callbacks when creating copy"
This breaks vCPU hotplug, because when starting a domain, we
create a copy of domain definition (which becomes live XML) and
during the post parse callbacks we might adjust some tunings so
that vCPU hotplug is possible.

This reverts commit 581b7756af.
2016-10-04 18:00:02 +02:00
Michal Privoznik
581b7756af conf: Skip post parse callbacks when creating copy
When creating a copy of virDomainDef we save ourselves the
trouble of writing deep-copy functions and just format and parse
back domain/device XML. However, the XML we are parsing was
already fully formatted - there is no reason to run post parse
callbacks (which fill in blanks - there are none!).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
4172ae371b qemuDomainDefAssignAddresses: Fetch caps from domain object
Just like we did two commits ago, don't try to fetch capabilities
for non-existing binary. Re-use the ones we have for running
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
1e501043f7 qemuDomainDeviceDefPostParse: Fetch caps from domain object
Just like we did two commits ago, don't try to fetch capabilities
for non-existing binary. Re-use the ones we have for running
domain.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
70b36a7b7e qemuDomainDefPostParse: Fetch qemuCaps from domain object
We can't rely on def->emulator path. It may be provided by user
as we give them opportunity to provide their own XML for
migration. Therefore the path may point to just whatever binary
(or even to a non-existent file). Moreover, this path is meant
for destination, but the capabilities lookup is done on source.
What we can do is to assume same capabilities for post parse
callbacks as the running domain has. They will be used just to
add some default models/controllers/devices/... anyway.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
cf198684a8 conf: Extend virDomainDefAssignAddressesCallback for parseOpaque
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
78ab5dcea0 conf: Extend virDomainDeviceDefPostParse for parseOpaque
Just like virDomainDefPostParseCallback has gained new
parseOpaque argument, we need to follow the logic with
virDomainDeviceDefPostParse.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
2e056b5c51 virDomainDefCopy: Introduce @parseOpaque argument
We want to pass the proper opaque pointer instead of NULL to
virDomainDefParseString.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
c41b989112 virDomainDefParse{File,String}: Introduce @parseOpaque argument
We want to pass the proper opaque pointer instead of NULL to
virDomainDefParse and subsequently virDomainDefParseNode too.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Michal Privoznik
940d91c55b virDomainDefPostParse: Introduce @parseOpaque argument
Some callers might want to pass yet another pointer to opaque
data to post parse callbacks. The driver generic one is not
enough because two threads executing post parse callback might
want to see different data (e.g. domain object pointer that
domain def belongs to).

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-26 16:50:12 +02:00
Jiri Denemark
7ce711a30e qemu: Update guest CPU def in live XML
Storing the updated CPU definition in the live domain definition saves
us from having to update it over and over when we need it. Not to
mention that we will soon further update the CPU definition according to
QEMU once it's started.

A highly wanted side effect of this patch, libvirt will pass all CPU
features explicitly specified in domain XML to QEMU, even those that are
already included in the host model.

This patch should fix the following bugs:
    https://bugzilla.redhat.com/show_bug.cgi?id=1207095
    https://bugzilla.redhat.com/show_bug.cgi?id=1339680
    https://bugzilla.redhat.com/show_bug.cgi?id=1371039
    https://bugzilla.redhat.com/show_bug.cgi?id=1373849
    https://bugzilla.redhat.com/show_bug.cgi?id=1375524
    https://bugzilla.redhat.com/show_bug.cgi?id=1377913

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2016-09-22 15:40:09 +02:00
Jiri Denemark
3b6be3c0c5 cpu: Rework cpuUpdate
The reworked API is now called virCPUUpdate and it should change the
provided CPU definition into a one which can be consumed by the QEMU
command line builder:

    - host-passthrough remains unchanged
    - host-model is turned into custom CPU with a model and features
      copied from host
    - custom CPU with minimum match is converted similarly to host-model
    - optional features are updated according to host's CPU

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2016-09-22 15:40:09 +02:00
Jiri Denemark
b27adaed37 qemu: Propagate virCapsPtr to virQEMUCapsNewForBinaryInternal
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2016-09-22 15:40:08 +02:00
Martin Kletzander
0f61d7b5f2 qemu: Abstract shmem socket path preparation
Put it into qemuDomainPrepareShmemChardev() so it can be used later.
Also don't fill in the path unless the server option is enabled.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2016-09-20 15:42:43 +02:00
Peter Krempa
64bc75f756 qemu: domain: Don't infer vcpu state
Use the state information (online, hotpluggable) provided by the monitor
code rather than trying to infer it. This fixes an issue where on
architectures that require hotplug of multiple threads at once the
sub-cores would get updated as offline on daemon restart thus creating
an invalid configuration.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1375783
2016-09-14 12:56:57 +02:00
Jiri Denemark
56258a388f qemu: Don't use query-migrate on destination
When migration fails, we need to poke QEMU monitor to check for a reason
of the failure. We did this using query-migrate QMP command, which is
not supposed to return any meaningful result on the destination side.
Thus if the monitor was still functional when we detected the migration
failure, parsing the answer from query-migrate always failed with the
following error message:

    "info migration reply was missing return status"

This irrelevant message was then used as the reason for the migration
failure replacing any message we might have had.

Let's use harmless query-status for poking the monitor to make sure we
only get an error if the monitor connection is broken.

https://bugzilla.redhat.com/show_bug.cgi?id=1374613

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2016-09-12 15:56:10 +02:00
Peter Krempa
6e19cc59a6 qemu: domain: Clear startup policy for dropped removable media
When a source image is dropped when missing due to startup policy the
policy needs to be cleared since it was relevant only for the given
storage source. New sources need to update it if needed.
2016-09-12 09:54:36 +02:00
Michal Privoznik
c56cdf2593 conf: Add support for virtio-net.rx_queue_size
https://bugzilla.redhat.com/show_bug.cgi?id=1366989

QEMU added another virtio-net tunable [1]. It basically allows
users to set the size of RX virtio ring. But because virtio-net
uses two separate ring buffers to pass data from/to guest they
named it explicitly rx_queue_size. We should expose it in our XML
too.

1: http://lists.nongnu.org/archive/html/qemu-devel/2016-08/msg02029.html

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-09-09 16:16:59 +02:00