This adds a new sd_pid_get_cgroup() call to sd-login which may be used
to query the control path of a process. This is useful for programs when
making use of delegation units, in order to figure out which subtree has
been delegated.
In light of the unified control group hierarchy this is finally safe to
do, hence let's add a proper API for it, to make it easier to use this.
Martin Pitt [Fri, 4 Sep 2015 14:34:21 +0000 (16:34 +0200)]
tests: Skip tests which need to access /sys/fs/cgroup if that is not available
Commit efdb023 ("core: unified cgroup hierarchy support") introduced a new
error ENOEXEC in cg_unified() if /sys/fs/cgroup/ is not available. Adjust the
"skip" checks in various tests accordingly.
Add a corresponding "skip" check to test-bus-creds as well, as
sd_bus_creds_new_from_pid() now calls cg_unified() as well.
This re-fixes "make check" in build chroots without /sys/fs/cgroup.
Hans de Goede [Fri, 4 Sep 2015 13:20:15 +0000 (15:20 +0200)]
hwdb: Add Thinkpad T550 / W550s to 70-pointingstick.hwdb
Like many other recent thinkpads the factory default pointingstick
sensitivity on these devices is quite low, making the pointingstick
very slow in moving the cursor.
This extends the existing hwdb rules for tweaking the sensitivity to
also apply to the T550 / W550s models.
David Herrmann [Fri, 4 Sep 2015 09:13:32 +0000 (11:13 +0200)]
bus-proxy: increase NOFILE limit
The bus-proxy manages the kdbus connections of all users on the system
(regarding the system bus), hence, it needs an elevated NOFILE.
Otherwise, a single user can trigger ENFILE by opening NOFILE connections
to the bus-proxy.
Note that the bus-proxy still does per-user accounting, indirectly via
the proxy/fake API of kdbus. Hence, the effective per-user limit is not
raised by this. However, we now prevent one user from consuming the whole
FD limit of the shared proxy.
Also note that there is no *perfect* way to set this. The proxy is a
shared object, so it needs a larger NOFILE limit than the highest limit
of all users. This limit can be changed dynamically, though. Hence, we
cannot protect against it. However, a raised NOFILE limit is a privilege,
so we just treat it as such and basically allow these privileged users to
be able to consume more resources than normal users (and, maybe, cause
some limits to be exceeded by this).
Right now, kdbus hard-codes 1024 max connections per user on each bus.
However, we *must not* rely on this. This limits could be easily dropped
entirely, as the NOFILE limit is a suitable limit on its on.
cgroups: delegation to unprivileged services is safe in the unified hierarchy
Delegation to unpriviliged processes is safe in the unified hierarchy,
hence allow it. This has the benefit of permitting "systemd --user"
instances to further partition their resources between user services.
Makre sure we always return sensible errors for the various, following
the same rules, and document them in a comment in sd-login.c. Also,
update all relevant man pages accordingly.
RT signals operate in a queue, and we should be careful to never merge
two queued signals into one. Hence, makes sure we only ever dequeue a
single signal at a time and leave the remaining ones queued in the
signalfd. In order to implement correct priorities for the signals
introduce one signalfd per priority, so that we only process the highest
priority signal at a time.
nspawn: enable all controllers we can for the "payload" subcgroup we create
In the unified hierarchy delegating controller access is safe, hence
make sure to enable all controllers for the "payload" subcgroup if we
create it, so that the container will have all controllers enabled the
nspawn service itself has.
cgroup-util: make cg_pid_get_path() return -ENODATA when controller can't be found
If the controller managed by systemd cannot found in /proc/$PID/cgroup,
return ENODATA, the usual error for cases where the data being looked
for does not exist, even if the process does.
cgroup: make sure cg_is_empty_recursive() returns 1 for non-existing cgroups
Previously, on the legacy hierarchy a non-existing cgroup was considered
identical to an empty one, but the unified hierarchy the check for a
non-existing one returned ENOENT.
Let's move the actual cgroup part of it into a new separate function
manager_get_unit_by_pid_cgroup(), and then make
manager_get_unit_by_pid() just a wrapper that also checks the two pid
hashmaps.
Then, let's make sure the various calls that want to deliver events to
the owners of a PID check both hashmaps and the cgroup and deliver the
event to *each* of them. OTOH make sure bus calls like GetUnitByPID()
continue to check the PID hashmaps first and the cgroup only as
fallback.
This simply factors out the uid validation checks from parse_uid() and
uses them everywhere. This simply verifies that the passed UID is
neither 64bit -1 nor 32bit -1.
macro: introduce new PID_TO_PTR macros and make use of them
This adds a new PID_TO_PTR() macro, plus PTR_TO_PID() and makes use of
it wherever we maintain processes in a hash table. Previously we
sometimes used LONG_TO_PTR() and other times ULONG_TO_PTR() for that,
hence let's make this more explicit and clean up things.
David Herrmann [Thu, 3 Sep 2015 13:18:06 +0000 (15:18 +0200)]
udev: ignore ENOEXEC from cgroup lookup
The recent cgroup-rework changed the error code for un-mounted cgroupfs to
ENOEXEC. Make sure udev ignores it just like ENOENT and does not spill
warnings on the screen.
Tom Gundersen [Tue, 25 Aug 2015 12:12:19 +0000 (14:12 +0200)]
udev: net_id - support predictable ifnames on virtio buses
Virtio buses are undeterministically enumerated, so we cannot use them as a basis
for deterministic naming (see bf81e792f3c0). However, we are guaranteed that there
is only ever one virtio bus for every parent device, so we can simply skip over
the virtio buses when naming the devices.
This patch set adds full support the new unified cgroup hierarchy logic
of modern kernels.
A new kernel command line option "systemd.unified_cgroup_hierarchy=1" is
added. If specified the unified hierarchy is mounted to /sys/fs/cgroup
instead of a tmpfs. No further hierarchies are mounted. The kernel
command line option defaults to off. We can turn it on by default as
soon as the kernel's APIs regarding this are stabilized (but even then
downstream distros might want to turn this off, as this will break any
tools that access cgroupfs directly).
It is possibly to choose for each boot individually whether the unified
or the legacy hierarchy is used. nspawn will by default provide the
legacy hierarchy to containers if the host is using it, and the unified
otherwise. However it is possible to run containers with the unified
hierarchy on a legacy host and vice versa, by setting the
$UNIFIED_CGROUP_HIERARCHY environment variable for nspawn to 1 or 0,
respectively.
The unified hierarchy provides reliable cgroup empty notifications for
the first time, via inotify. To make use of this we maintain one
manager-wide inotify fd, and each cgroup to it.
This patch also removes cg_delete() which is unused now.
On kernel 4.2 only the "memory" controller is compatible with the
unified hierarchy, hence that's the only controller systemd exposes when
booted in unified heirarchy mode.
This introduces a new enum for enumerating supported controllers, plus a
related enum for the mask bits mapping to it. The core is changed to
make use of this everywhere.
This moves PID 1 into a new "init.scope" implicit scope unit in the root
slice. This is necessary since on the unified hierarchy cgroups may
either contain subgroups or processes but not both. PID 1 hence has to
move out of the root cgroup (strictly speaking the root cgroup is the
only one where processes and subgroups are still allowed, but in order
to support containers nicey, we move PID 1 into the new scope in all
cases.) This new unit is also used on legacy hierarchy setups. It's
actually pretty useful on all systems, as it can then be used to filter
journal messages coming from PID 1, and so on.
The root slice ("-.slice") is now implicitly created and started (and
does not require a unit file on disk anymore), since
that's where "init.scope" is located and the slice needs to be started
before the scope can.
To check whether we are in unified or legacy hierarchy mode we use
statfs() on /sys/fs/cgroup. If the .f_type field reports tmpfs we are in
legacy mode, if it reports cgroupfs we are in unified mode.
This patch set carefuly makes sure that cgls and cgtop continue to work
as desired.
When invoking nspawn as a service it will implicitly create two
subcgroups in the cgroup it is using, one to move the nspawn process
into, the other to move the actual container processes into. This is
done because of the requirement that cgroups may either contain
processes or other subgroups.
sd-bus: when connecting to a container, don't fall back to host bus
We should never connect to the host bus as fallback if connecting to a
container failed via one method. Otherwise connecting to a dbus1
container will always result in a connection to the host.
sd-bus: when connecting to a kdbus container bus pass error up
We rely on the correct error used when opening the kdbus device node,
hence let's make sure we pass it up from the namespaced child process to
the process which actually wants to connect.
When the user wants to explicitly send our own PID a signal, then do so.
Don't follow up SIGABRT with a SIGHUP if send_sighup is enabled. At that
point the process should have segfaulted, hence there's no point in
following up with a SIGHUP.
Send only termination signals to ourselves, never KILL or ABRT signals.
Always say when we ignore errors. Cast calls whose return value we
knowingly ingore to (void). Use "bool" where we actually mean a boolean,
even if we return it as an int later on.
core: when looking for the unit for a process, look at the PID hashmaps first
It's cheaper that going to cgroupfs, and also usually the better choice
since it's not racy and can map PIDs even if they were moved to a
different unit.
cgroup: drop "ignore_self" argument from cg_is_empty()
In all cases where the function (or cg_is_empty_recursive()) ignoring
the calling process is actually wrong, as a process keeps a cgroup busy
regardless if its the current one or another. Hence, let's simplify
things and drop the "ignore_self" parameter.
units: enable waiting for unit termination in certain cases
The legacy cgroup hierarchy does not support reliable empty
notifications in containers and if there are left-over subgroups in a
cgroup. This makes it hard to correctly wait for them running empty, and
thus we previously disabled this logic entirely.
With this change we explicitly check for the container case, and whether
the unit is a "delegation" unit (i.e. one where programs may create
their own subgroups). If we are neither in a container, nor operating on
a delegation unit cgroup empty notifications become reliable and thus we
start waiting for the empty notifications again.
This doesn't really fix the general problem around cgroup notifications
but reduces the effect around it.
(This also reorders #include lines by their focus, as suggsted in
CODING_STYLE. We have to add "virt.h", so let's do that at the right
place.)
Michal Sekletar [Tue, 1 Sep 2015 14:02:58 +0000 (16:02 +0200)]
selinux: always use *_raw API from libselinux
When mcstransd* is running non-raw functions will return translated SELinux
context. Problem is that libselinux will cache this information and in the
future it will return same context even though mcstransd maybe not running at
that time. If you then check with such context against SELinux policy then
selinux_check_access may fail depending on whether mcstransd is running or not.
To workaround this problem/bug in libselinux, we should always get raw context
instead. Most users will not notice because result of access check is logged
only in debug mode.
* SELinux context translation service, which will translates labels to human
readable form
Martin Pitt [Tue, 1 Sep 2015 08:51:15 +0000 (10:51 +0200)]
logind: Listen to WMI hotkeys to catch SW_DOCK state/events
On Dell and HP laptops the dock state/events (SW_DOCK) come from the "{Dell,HP}
WMI hotkeys" input devices. Tag them as power-switch so that login actually
considers them. Use a general match in case this affects other vendors, too.
core: Use extract_first_word in config_parse_join_controllers
Related to the TODO item to replace FOREACH_WORD_QUOTED with it.
Tested by setting `JoinControllers=cpu,cpuacct,memory net_cls,blkio' in
/etc/systemd/system.conf, rebooting the system with the patched binaries
and checking that the desired setup was created by inspecting the
entries under /sys/fs/cgroup.
core: Use extract_first_word in config_parse_cpu_affinity2
Related to the TODO item to replace FOREACH_WORD_QUOTED with it.
Tested by setting `CPUAfinity=0 1' (and other similar settings) in
/etc/systemd/system.conf, booting the system with the patched binaries
(and also using `systemctl daemon-reload` to reconfigure) and checking
that /proc/1/status indicates only CPUs 0 and 1 are allowed for PID 1.