Commit Graph

425 Commits

Author SHA1 Message Date
Marc-André Lureau
0755234389 qemu: add a flag to the cookie to prevent slirp-helper setup
For VM started and migrated/saved without slirp-helpers, let's prevent
the automatic setup (as it would fail to migrate otherwise).

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-09-06 12:47:47 +02:00
Marc-André Lureau
6d5a9b9ed0 qemu-domain: save and restore slirp state
Save & restore the slirp helper PID associated with a network
interface & the probed features.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-09-06 12:47:47 +02:00
Marc-André Lureau
5d732dbb35 qemu: add qemuDomainNetworkPrivate
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-09-06 12:47:47 +02:00
Marc-André Lureau
2b0251af68 qemu: add dbus-vmstate
Add dbusVMStates to keep a list of dbus-vmstate objects needed for
migration. They are populated on the command line during start or
qemuDBusVMStateAdd/Remove() will hotplug them as needed.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-09-06 12:47:47 +02:00
Peter Krempa
510d154a0b qemu: Prevent storage causing too much nested XML
Since libvirt stores the backing chain into the XML in a nested way it
is the prime possibility to hit libxml2's parsing limit of 256 layers.

Introduce code which will crawl the backing chain and verify that it's
not too deep. The maximum nesting is set to 200 layers so that there's
still some space left for additional properties or nesting into snapshot
XMLs.

The check is applied to all disk use cases (starting, hotplug, media
change) as well as block copy which changes image and snapshots.

We simply report an error and refuse the operation.

Without this check a restart of libvirtd would result in the status XML
failing to be parsed and thus losing the VM.

https://bugzilla.redhat.com/show_bug.cgi?id=1524278

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-09-06 08:12:21 +02:00
Peter Krempa
a0b61591f2 qemu: Extract and store vCPU properties as qemu returned them
In addition to the data that libvirt needs and extracts internally,
copy and store the whole 'props' JSON sub-object of the data returned by
query-hotpluggable-cpus for future use.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2019-08-29 16:36:26 +02:00
Ján Tomko
126ac61ea3 conf: domain: use generic XML namespace types
Now that virDomainXMLNamespace matches virXMLNamespace,
we no longer need to keep both around.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
2019-08-21 10:29:20 +02:00
Jiri Denemark
900c595249 qemu: Pass qemuCaps to qemuDomainDefFormatBufInternal
Since qemuDomainDefPostParse callback requires qemuCaps, we need to make
sure it gets the capabilities stored in the domain's private data if the
domain is running. Passing NULL may cause QEMU capabilities probing to
be triggered in case QEMU binary changed in the meantime. When this
happens while a running domain object is locked, QMP event delivered to
the domain before QEMU capabilities probing finishes will deadlock the
event loop.

This patch fixes all paths leading to qemuDomainDefFormatBufInternal.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-08-09 13:55:54 +02:00
Jiri Denemark
a42f889591 qemu: Pass qemuCaps to qemuDomainDefCopy
Since qemuDomainDefPostParse callback requires qemuCaps, we need to make
sure it gets the capabilities stored in the domain's private data if the
domain is running. Passing NULL may cause QEMU capabilities probing to
be triggered in case QEMU binary changed in the meantime. When this
happens while a running domain object is locked, QMP event delivered to
the domain before QEMU capabilities probing finishes will deadlock the
event loop.

This patch fixes all paths leading to qemuDomainDefCopy.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
2019-08-09 13:55:54 +02:00
Eric Blake
e3a4b8f461 backup: qemu: Add helper API for looking up node name
Qemu bitmap operations require knowing the node name associated with
the format layer (the qcow2 file); as upcoming patches will be
grabbing that information frequently, make a helper function to access
it.

Another potential benefit of this function is that we have a single
place where we could insert a QMP node-name scraping call if we don't
currently know the node name, when -blockdev is not supported;
however, the goal is that we hopefully don't ever have to do that
because we instead scrape node names only at the point where they
change.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-29 08:15:11 -05:00
Eric Blake
5f4e079650 backup: qemu: Implement metadata tracking for checkpoint APIs
A lot of this work heavily copies from the existing snapshot APIs.
What's more, this patch is (intentionally) very similar to the
checkpoint code just added in the test driver, to the point that qemu
checkpoints are not fully usable in this patch, but it at least
bisects and builds cleanly.  The separation between patches is done
because the grunt work of saving and restoring XML and tracking
relations between checkpoints is common to the test driver, while the
later patch adding integration with QMP is specific to qemu.

Also note that the interlocking to prevent checkpoints and snapshots
from existing at the same time will be a separate patch, to make it
easier to revert that restriction when we finally round out the design
for supporting interaction between the two concepts.

Signed-off-by: Eric Blake <eblake@redhat.com>
2019-07-29 08:09:13 -05:00
Peter Krempa
0a9fd83240 qemu: Detect managed persistent reservations in block job orphan chains
The PR manager is a property of the format layer in qemu so we need to
be able to track it also in the chains of orphaned block jobs.

Add a helper for qemu to look also into the blockjob state.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-07-18 17:59:34 +02:00
Peter Krempa
cbf4e3af70 qemu: Add handler for job state change event
Add support for handling the event either synchronously or
asynchronously using the event thread.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-07-18 17:59:34 +02:00
Peter Krempa
acff582915 qemu: domain: Add global table of blockjobs
Block jobs currently belong to disks only so we can look up the block
job data for them in the corresponding disks. This won't be the case
when using blockdev as certain jobs don't even correspond to a disk and
most of them can run on a part of the backing chain.

Add a global table of blockjobs which can be used to look up the data
for the blockjobs when the job events need to be processed.

The table is a hash table organized by job name and has a reference to
the job. New and running jobs will later be added to this table.
Reference counting will allow to reap job state for synchronous callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-07-18 17:59:34 +02:00
Peter Krempa
a3b0e09242 qemu: domain: Add helper for saving config XML
Similarly to qemuDomainSaveStatus add a helper to save the config XML
named qemuDomainSaveConfig.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-07-18 17:59:34 +02:00
Peter Krempa
997746b2df qemu: domain: Repurpose and export helper for saving domain status XML
Rename qemuDomainObjSaveJob and create a wrapper for it which does not
require 'driver' to be passed and export it so that other palces can
easily save the status XML without having to invoke virDomainSaveStatus
which has unpleasing parameters.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-07-18 17:59:34 +02:00
Peter Krempa
b84c09f41a qemu: domain: Export qemuDomainPrepareStorageSourceBlockdev
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-07-18 17:59:34 +02:00
Michal Privoznik
9f95552d17 qemu: De-duplicate some path definitions
There are some paths (e.g. /dev/vfio/vfio or /dev/mapper/control)
which are defined in qemu_domain.c and then in qemu_cgroup.c
again. This is suboptimal. Let's move paths into qemu_domain.h and
drop duplicate definitions.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Andrea Bolognani <abologna@redhat.com>
2019-07-03 09:33:45 +02:00
Peter Krempa
c6da5913d9 qemu: Add support for controling qemu capabilities via the qemu XML namespace
Similarly how we allow adding arbitrary command line arguments and
environment variables this patch introduces the ability to control
libvirt's perception of the qemu process by tweaking the capability bits
for testing purposes.

The idea is to allow developers and users either test a new feature by
enabling it early or disabling it to see whether it introduced
regressions.

This feature is not meant for production use though, so users should
handle it with care.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-06-21 15:24:06 +02:00
Peter Krempa
a967b2f0bd qemu: Move qemuDomainXmlNsDef(Free) from qemu_conf.(ch)
qemu_conf.c deals with the configuration file. Better fit for the
structure and freeing function will be qemu_domain.c where the rest of
the namespace parsing/formatting stuff resides.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-06-21 15:24:06 +02:00
Ján Tomko
466764346d qemu: domain: remove monJSON field
If we have a monitor, it is a JSON monitor.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Acked-by: Peter Krempa <pkrempa@redhat.com>
2019-06-20 13:47:41 +02:00
Jonathon Jongsma
5dad4b5d93 src/qemu: use #pragma once in headers
Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2019-06-19 17:12:30 +02:00
Peter Krempa
45b9ec5b09 qemu: Split entry points to qemuDomainStorageSourceChainAccessPrepare
Introduce qemuDomainStorageSourceChainAccess(Allow|Revoke) as entry
points to qemuDomainStorageSourceChainAccessPrepare for symmetry with
the functions for single backing chain elements.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-05-09 15:55:35 +02:00
Peter Krempa
3d36d666f8 qemu: Move and rename qemuHotplugPrepareDiskSourceAccess
Move it to qemu_domain.c and call it
qemuDomainStorageSourceChainAccessPrepare.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-05-09 15:55:35 +02:00
Peter Krempa
1a828a578e qemu: Rename qemuDomainDiskChainElement(Revoke|Prepare)
Use qemuDomainStorageSourceAccess(Allow|Revoke) instead.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-05-09 15:55:35 +02:00
Peter Krempa
285c5f28c4 util: Move enum convertors into virenum.(c|h)
virutil.(c|h) is a very gross collection of random code. Remove the enum
handlers from there so we can limit the scope where virtutil.h is used.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-10 09:12:04 +02:00
Nikolay Shirokovskiy
ab2eaa1492 qemu: Map suspended state reason to suspended event detail
Map is based on existing cases in code where we send suspended
event after changing domain state to paused.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
2019-04-04 10:36:03 +03:00
Nikolay Shirokovskiy
93c7d13eec qemu: Pass stop reason from qemuProcessStopCPUs to stop handler
Similar to commit [1] which saves and passes the running reason to
the RESUME event handler, during qemuProcessStopCPUs let's save and pass
the pause reason in the domain private data so that the STOP event
handler can use it.

[1] 5dab984ed : qemu: Pass running reason to RESUME event handler

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
2019-04-04 10:36:03 +03:00
Peter Krempa
f1a0d2277c qemu: domain: drop qemuDomainSupportsBlockJobs
It always returns true.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-04-03 11:58:10 +02:00
Eric Blake
a487890d37 snapshot: Refactor qemu to utilize virDomainMoment more
Use the common base class virDomainMoment for iterator callbacks
related to snapshots from the qemu code, so that when checkpoint
operations are introduced, they can share the same callbacks.

Simplify the code for qemuDomainSnapshotCurrent by better utilizing
virDomainMoment helpers.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-27 08:16:10 -05:00
Eric Blake
e055a816af snapshot: Rename virDomainSnapshotObjPtr
Now that the core of SnapshotObj is agnostic to snapshots and can be
shared with upcoming checkpoint code, it is time to rename the struct
and the functions specific to list operations. A later patch will
shuffle which file holds the common code. This is a fairly mechanical
patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-22 01:18:34 -05:00
Michal Privoznik
c2bc419131 qemu_hotplug: Fix a rare race condition when detaching a device twice
https://bugzilla.redhat.com/show_bug.cgi?id=1623389

If a device is detached twice from the same domain the following
race condition may happen:

1) The first DetachDevice() call will issue "device_del" on qemu
monitor, but since the DEVICE_DELETED event did not arrive in
time, the API ends claiming "Device detach request sent
successfully".

2) The second DetachDevice() therefore still find the device in
the domain and thus proceeds to detaching it again. It calls
EnterMonitor() and qemuMonitorSend() trying to issue "device_del"
command again. This gets both domain lock and monitor lock
released.

3) At this point, qemu sends us the DEVICE_DELETED event which is
going to be handled by the event loop which ends up calling
qemuDomainSignalDeviceRemoval() to determine who is going to
remove the device from domain definition. Whether it is the
caller that marked the device for removal or whether it is going
to be the event processing thread.

4) Because the device was marked for removal,
qemuDomainSignalDeviceRemoval() returns true, which means the
event is to be processed by the thread that has marked the device
for removal (and is currently still trying to issue "device_del"
command)

5) The thread finally issues the "device_del" command, which
fails (obviously) and therefore it calls
qemuDomainResetDeviceRemoval() to reset the device marking and
quits immediately after, NOT removing any device from the domain
definition.

At this point, the device is still present in the domain
definition but doesn't exist in qemu anymore. Worse, there is no
way to remove it from the domain definition.

Solution is to note down that we've seen the event and if the
second "device_del" fails, not take it as a failure but carry on
with the usual execution.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
ACKed-by: Peter Krempa <pkrempa@redhat.com>
2019-03-15 13:45:34 +01:00
Michal Privoznik
23018c0823 qemu_domain: Separate NVRAM VAR store file name generation
Move the code that (possibly) generates filename of NVRAM VAR
store into a single function so that it can be re-used later.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-12 15:29:43 +01:00
Eric Blake
7ff982f0bc qemu: Const-correct snapshot directory name
qemuDomainSnapshotWriteMetadata does not modify the directory name,
and making it const-correct aids in writing an upcoming patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-03-07 16:57:05 -06:00
Andrea Bolognani
0440d5e90f qemu: Move qemuDomainSupportsPCI() to qemu_domain
The function operates on a virDomainDef and is not tied to
device address assignment in any way, so it makes more sense
for it to live along with qemuDomainIs*() and the like.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2019-02-08 16:16:22 +01:00
Andrea Bolognani
68e26a9ea2 qemu: Make most qemuDomainMachine*() functions static
Ideally we'd make all of them static, but there are a few
cases where we don't have a virDomainDef instance handy and
so they are the only option.

For the few ones we're forced to keep exporting, document
through comments that the alternative is preferred.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2019-02-08 16:16:20 +01:00
Andrea Bolognani
9a5ce5cb29 qemu: Add arch parameter to qemuDomainMachine*()
We want the signatures to be consistent, and also we're
going to start using the additional parameter next.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2019-02-08 16:16:14 +01:00
Andrea Bolognani
4028d7a46a qemu: Move functions around
Make sure related functions, eg. all qemuDomainIs*(), are
close together instead of being sprinkled throughout both
the header and implementation file, and also that all
qemuDomainMachine*() functions are declared first since
we're going to make a bunch of them static later on.

Signed-off-by: Andrea Bolognani <abologna@redhat.com>
2019-02-08 16:16:12 +01:00
Peter Krempa
3b0856c4ba qemu: Clean up usage of qemuDomainUpdateCurrentMemorySize
Remove the uneeded attribute and return value.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
2019-02-08 10:11:20 +01:00
Cole Robinson
7662194bf3 Require a semicolon to VIR_ENUM_DECL calls
Missing semicolon at the end of macros can confuse some analyzers
(like cppcheck <filename>), and we have a mix of semicolon and
non-semicolon usage through the code. Let's standardize on using
a semicolon for VIR_ENUM_DECL calls.

Drop the semicolon from the final statement of the macro, so
the compiler will require callers to add a semicolon.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Cole Robinson <crobinso@redhat.com>
2019-02-03 17:46:29 -05:00
Daniel P. Berrangé
a507edef33 qemu: pass virDomainDeviceInfo by reference
The virDomainDeviceInfo parameter is a large struct so it is preferrable
to pass it by reference instead of by value.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2019-01-31 10:38:36 +00:00
Peter Krempa
33b0a3bab8 qemu: domain: Allow overriding disk source in qemuDomainDetermineDiskChain
When we need to detect a chain for a image which will become the new
source for a disk (e.g. after a disk media change or a blockjob) we'd
need to replace disk->src temporarily to do so.

Move the 'disksrc' temporary variable to an argument and adjust callers.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-30 17:20:38 +01:00
Ján Tomko
2e2b0d69a9 qemu: add support for encrypted VNC TLS keys
Use the password stored in the secret driver under
the uuid specified by the vnc_tls_x509_secret_uuid
option in qemu.conf.

https://bugzilla.redhat.com/show_bug.cgi?id=1602418

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-22 12:18:28 +01:00
Ján Tomko
ea3c3f8846 qemu: add qemuDomainGraphicsPrivate data with a tlsAlias
Also introduce the necessary callbacks.

Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2019-01-22 12:18:28 +01:00
Peter Krempa
89a877b312 qemu: Consolidate disk blockjob variables into a structure
Struct qemuDomainDiskPrivate was holding multiple variables connected to
a disk block job. Consolidate them into a new struct qemuBlockJobData.

This will also allow simpler extensions to the block job mechanisms.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2019-01-17 17:12:50 +01:00
Yuval Shaia
ed357cef18 qemu: Process RDMA GID state change event
This event is emitted on the monitor when a GID table in pvrdma device
is modified and the change needs to be propagate to the backend RDMA
device's GID table.

The control over the RDMA device's GID table is done by updating the
device's Ethernet function addresses.
Usually the first GID entry is determine by the MAC address, the second
by the first IPv6 address and the third by the IPv4 address. Other
entries can be added by adding more IP addresses. The opposite is the
same, i.e. whenever an address is removed, the corresponding GID entry
is removed.

The process is done by the network and RDMA stacks. Whenever an address
is added the ib_core driver is notified and calls the device driver's
add_gid function which in turn update the device.

To support this in pvrdma device we need to hook into the create_bind
and destroy_bind HW commands triggered by pvrdma driver in guest.
Whenever a changed is made to the pvrdma device's GID table a special
QMP messages is sent to be processed by libvirt to update the address of
the backend Ethernet device.

Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2019-01-09 10:26:29 +01:00
Nikolay Shirokovskiy
318d807a0b qemu: don't log error for missing optional storage sources on stats
Every time we call all domain stats for inactive domain with
unavailable storage source we get error message in logs [1]. It's a bit noisy.
While it's arguable whether we need such message or not for mandatory
disks we would like not to see messages for optional disks. Let's
filter at least for cases of local files. Fixing other cases would
require passing flag down the stack to .backendInit of storage
which is ugly.

Stats for active domain are fine because we either drop disks
with unavailable sources or clean source which is handled
by virStorageSourceIsEmpty in qemuDomainGetStatsOneBlockFallback.

We have these logs for successful stats since 25aa7035d (version 1.2.15)
which in turn fixes 596a13713 (version 1.2.12 )which added substantial
stats for offline disks.

[1] error message example:
qemuOpenFileAs:3324 : Failed to open file '/path/to/optional/disk': No such file or directory

Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
2018-12-21 12:13:31 +03:00
Daniel P. Berrangé
568a417224 Enforce a standard header file guard symbol name
Require that all headers are guarded by a symbol named

  LIBVIRT_$FILENAME

where $FILENAME is the uppercased filename, with all characters
outside a-z changed into '_'.

Note we do not use a leading __ because that is technically a
namespace reserved for the toolchain.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-14 10:47:13 +00:00
Daniel P. Berrangé
600462834f Remove all Author(s): lines from source file headers
In many files there are header comments that contain an Author:
statement, supposedly reflecting who originally wrote the code.
In a large collaborative project like libvirt, any non-trivial
file will have been modified by a large number of different
contributors. IOW, the Author: comments are quickly out of date,
omitting people who have made significant contribitions.

In some places Author: lines have been added despite the person
merely being responsible for creating the file by moving existing
code out of another file. IOW, the Author: lines give an incorrect
record of authorship.

With this all in mind, the comments are useless as a means to identify
who to talk to about code in a particular file. Contributors will always
be better off using 'git log' and 'git blame' if they need to  find the
author of a particular bit of code.

This commit thus deletes all Author: comments from the source and adds
a rule to prevent them reappearing.

The Copyright headers are similarly misleading and inaccurate, however,
we cannot delete these as they have legal meaning, despite being largely
inaccurate. In addition only the copyright holder is permitted to change
their respective copyright statement.

Reviewed-by: Erik Skultety <eskultet@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-12-13 16:08:38 +00:00
Michal Privoznik
c658764dec qemu: Don't use -mem-prealloc among with .prealloc=yes
https://bugzilla.redhat.com/show_bug.cgi?id=1624223

There are two ways to request memory preallocation on cmd line:
-mem-prealloc and .prealloc attribute for a memory-backend-file.
However, as it turns out it's not safe to use both at the same
time. If -mem-prealloc is used then qemu will fully allocate the
memory (this is done by actually touching every page that has
been allocated). Then, if .prealloc=yes is specified,
mbind(flags = MPOL_MF_STRICT | MPOL_MF_MOVE) is called which:

a) has to (possibly) move the memory to a different NUMA node,
b) can have no effect when hugepages are in play (thus ignoring user
request to place memory on desired NUMA nodes).

Prefer -mem-prealloc as it is more backward compatible
compared to switching to "-numa node,memdev=  + -object
memory-backend-file".

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2018-12-13 09:55:38 +01:00