Now updating my machines to stretch, I see this issue is still present,
now in systemd version 232-25. The same steps can reproduce:
- Set up cgroups e.g. adding TaskIDs to /sys/fs/cgroup/cpu/DIR/tasks
files. (I use cgrulesengd from package cgroup-tools, but any other
use of cgroups is equally affected.)
- Then when you use systemd commands:
systemctl daemon-reload
systemctl start anacron
you will see your cgroups (your tasks files) becoming empty.
Command daemon-reload seems to happen within "apt-get dist-upgrade"
sequences, and "start anacron" happens nightly. (Some other systemd
commands may also affect.)
and the "same" fix applies: new patch file below, for changed sources.
Please update the list of versions affected by the bug. Maybe you could
set the severity back to critical: it does break unrelated software in
a default setup.
(Distressing how this bug did not get fixed in two years...)
Thanks, Paul
--
Paul Szabo p...@maths.usyd.edu.au http://www.maths.usyd.edu.au/u/psz/
School of Mathematics and Statistics University of Sydney Australia
diff -r -U17 a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
--- a/src/basic/cgroup-util.c 2017-07-20 09:32:36.000000000 +1000
+++ b/src/basic/cgroup-util.c 2017-07-20 09:41:31.000000000 +1000
@@ -369,34 +369,44 @@
int cg_migrate(
const char *cfrom,
const char *pfrom,
const char *cto,
const char *pto,
CGroupFlags flags) {
bool done = false;
_cleanup_set_free_ Set *s = NULL;
int r, ret = 0;
pid_t my_pid;
assert(cfrom);
assert(pfrom);
assert(cto);
assert(pto);
+ /*
+ * PSz 25 Oct 2015
+ * An empty "to" path is surely wrong (do not annoy cgroups that not ours)
+ */
+ if (!strlen(pto)) {
+ /* log_warning("Debug: cg_migrate skip from (%s)%s to (%s)%s", cfrom, pfrom, cto, pto); */
+ return ret;
+ }
+ /* log_warning("Debug: cg_migrate do from (%s)%s to (%s)%s", cfrom, pfrom, cto, pto); */
+
s = set_new(NULL);
if (!s)
return -ENOMEM;
my_pid = getpid();
do {
_cleanup_fclose_ FILE *f = NULL;
pid_t pid = 0;
done = true;
r = cg_enumerate_processes(cfrom, pfrom, &f);
if (r < 0) {
if (ret >= 0 && r != -ENOENT)
return r;
return ret;
