Commit Graph

581 Commits

Author SHA1 Message Date
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