Okay, here is the deal. Currently, the way we build namespace is
very fragile. It is done from pre-exec hook when starting a
domain, after we mass closed all FDs and before we drop
privileges and exec() QEMU. This fact poses some limitations onto
the namespace build code, e.g. it has to make sure not to keep
any FD opened (not even through a library call), because it would
be leaked to QEMU. Also, it has to call only async signal safe
functions. These requirements are hard to meet - in fact as of my
commit v6.2.0-rc1~235 we are leaking a FD into QEMU by calling
libdevmapper functions.
To solve this issue and avoid similar problems in the future, we
should change our paradigm. We already have functions which can
populate domain's namespace with nodes from the daemon context.
If we use them to populate the namespace and keep only the bare
minimum in the pre-exec hook, we've mitigated the risk.
Therefore, the old qemuDomainBuildNamespace() is renamed to
qemuDomainUnshareNamespace() and new qemuDomainBuildNamespace()
function is introduced. So far, the new function is basically a
NOP and domain's namespace is still populated from the pre-exec
hook - next patches will fix it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The aim to make it look as close to
qemuDomainNamespaceSetupDisk() as possible. The latter will call
the former and this change makes that diff easier to read.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Every caller does the same - counts the number of items in a
string list they have, only to pass the number to
qemuDomainNamespaceMknodPaths(). This is needless - the function
can accept the string list and count the items itself.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
While the previous commit prepared the helper function run in a
forked off helper (with corresponding struct), this commit
modifies the caller, which now create all files requested in a
single process and does not fork off for every single path.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
So far, when attaching a device needs two or more /dev nodes
created into a domain, we fork off and run the helper for every
node separately. For majority of devices this is okay, because
they need no or one node created anyway. But the idea is to use
this attach code to build the namespace when starting a domain,
in which case there will be way more nodes than one.
To achieve this, the recursive approach for handling symlinks has
to be turned into an iterative one.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
When attaching a device into a domain, the corresponding /dev
node might need to be created in the domain's namespace. For some
types of files we call mknod(), for symlinks we call symlink(),
but for others - which exist in the host namespace - we need to
so called 'bind mount' them (which is a way of passing a
file/directory between mount namespaces). There is this condition
in qemuDomainAttachDeviceMknodRecursive() which decides whether a
bind mount will be used, move it into a separate function so that
it can be reused later.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This structure is going to be used from not only device attach
code, but also when building the namespace. Moreover, the code
lives in a separate file so the chances of clashing with another
name are minimal.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
It's not really a problem since this is a helper process that
dies as soon as the helper function returns, but the cleanup code
will be replaced with a function soon and this change prepares
the code for that.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
While qemuDomainNamespaceMknodPaths() doesn't actually create
files in the namespace in one go (it forks for each path), it a
few commits time it will.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Functions that create a device node after domain startup (used
from hotplug) will get a list of paths they want to create and
eventually call qemuDomainNamespaceMknodPaths() which then checks
whether domain mount namespace is enabled in the first place.
Alternatively, on device hotunplug, we might want to delete a
path inside domain namespace in which case
qemuDomainNamespaceUnlinkPaths() checks whether the namespace is
enabled. While this is not dangerous, it certainly burns a couple
of CPU cycles needlessly.
Check whether mount namespace is enabled upfront.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
There is a lot of functions called from
qemuDomainBuildNamespace() that accept @cfg
(virQEMUDriverConfigPtr) as an argument and don't use it.
Historically, it was done so that all qemuDomainSetupAll*()
functions look the same.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The name of this function is not very helpful, because it doesn't
create anything, it just flips a bit in a bitmask when domain is
starting up. Move the function internals into qemu_process.c and
forget the function ever existed.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The qemu_domain.c file is big as is and we should split it into
separate semantic blocks. Start with code that handles domain
namespaces.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
'docutils' add line saying "Contents:" on top of the table of contents.
We don't have that in other documents nor it's really necessary. Hide it
in the stylesheet as we can select it easily.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The table of contents of documents generated from RST is quite squeezed
together. Add 2em-s worth of vertical separation on each side.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Docutils don't generate <code> for inline literals (``blah``) in rst
but rather put them in the '.literal' class. Add a selector for making
them bold when used in definition list headers.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
'docutils' add a stylesheet to the output html file for direct
consumption. Since we use the html files just as an intermediate step
which is post-processed to add our own stylesheet and drop the docutils
one in the process we can ask 'rst2html' to not add any for an
intermediate file with less garbage.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Show various usage of filters including some useful examples.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Kashyap Chamarthy <kchamart@redhat.com>
Promote the 'What to attach?' section to a first level heading and
request also the XML config of a VM, coredump backtrace if something
crashed and ask to not tear down the environment for the possibility to
ask for additional data.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Kashyap Chamarthy <kchamart@redhat.com>
NEWS.rst is based in the root of the repository and 'hvsupport.html'
doesn't have a backing file which can be edited since it's fully
generated. Our 'contribute -> edit this page' link on the bottom of the
page is wrong in those cases.
Fix it by adding the contribute section only when there's a source and
base the 'source' of a html file in the root of the repository.
Along with that we need to modify the scripts/meson-html-gen.py script
to accept optional 'pagesrc' and the XSL template to skip the
'contribute' section when we don't have a source.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Just convert 'docs_html_in_files' into 'docs_html_in_gen'. The target
definitions for those were almost the same.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
These variables are only used for assignment and have
no other effect.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
In virCgroupV2BindMount there is an unused variable containing
what seem to be tmpfs mount options.
Delete it. Unlike with cgroups v1, we do not create a tmpfs
here.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Now that everything uses g_strfreev, this function is no longer
needed.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Both accept a NULL value gracefully and virStringFreeList
does not zero the pointer afterwards, so a straight replace
is safe.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
The g_strdupv function from GLib provides
the same functionality.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Also remove the temporary variable - even virStringListCopy
aborts on OOM now.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
virLoginShellGetShellArgv was not dereferencing the pointer
to the string list containing the shell parameters from the
config file, thus setting some random number as shargvlen.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Fixes: 740e4d7052
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
After the split of virsh to multiple files, and the subsequent
split to vsh/virt-admin, there are quite a few leftovers.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Last usage out of virlog.c was removed by
commit 91268c715c
node_device_udev: remove deprecated logging function
Also drop the virbuffer.h include - it seems it was never used
for anything else than the transitive stdarg.h include.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
This function calls virLogVMessage. Move it below the definition
of virLogVMessage so it can call it even without a prototype.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
The XML function is needed in the C file,
not in the header.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
This file is using XML functions without including
the header.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
It was needed for virAsprintf, which is now dropped.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Fixes: 33ed622106
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
The commands daemon-log-filters and daemon-log-outputs
are used both for getting and setting the variables.
But the getter receives an allocated string, which
we do not free.
Use separate variables for the getter and the setter
to get rid of the memory leak and to stop casting
away the const.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Some of libvirt APIs return the number of elements, but we
don't need them, only whether the API failed or not.
Delete the redundant variables.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Although virXPathNodeSet is unlikely to return -1, we should
check for it properly or not at all.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
We use an array of size VIR_NODE_MEMORY_STATS_FIELD_LENGTH
to store the string read from sysfs, but pass unbound "%s"
to sscanf.
Make the array larger by one and simply stringify that
constant as the field width specifier.
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
The 'dom' pointer is already dereferenced earlier.
src/vz/vz_sdk.c:249:24: warning: Either the condition 'if(dom)'
is redundant or there is possible null pointer dereference:
dom. [nullPointerRedundantCheck]
Signed-off-by: Ján Tomko <jtomko@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Provide debug log configuration insight in our kbase.
There are two modifications of the document compared to the wiki
version:
1) The link for reporting a bug agains libvirt was modified to use the
gitlab issue tracker.
2) The link to URI specification details is changed to 'https' protocol.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
