A patch below, functionally identical to my previous. But this seems
neater, showing the intent more clearly: clearer that this is a "true"
bug in systemd.
Cheers, Paul
--
Paul Szabo [email protected] http://www.maths.usyd.edu.au/u/psz/
School of Mathematics and Statistics University of Sydney Australia
diff -r -U23 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 2017-07-23 13:51:28.000000000 +1000
@@ -363,46 +363,60 @@
return r;
}
return ret;
}
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 are not ours).
+ * PSz 23 Jul 2017
+ * Cannot happen anymore(?), see cg_migrate_recursive_fallback()
+ * below... log if it does!
+ */
+ if (!strlen(pto)) {
+ log_warning("PSz debug: cg_migrate skip from (%s)%s to (%s)%s", cfrom, pfrom, cto, pto);
+ return ret;
+ }
+ /* log_warning("PSz 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;
}
while ((r = cg_read_pid(f, &pid)) > 0) {
/* This might do weird stuff if we aren't a
* single-threaded program. However, we
@@ -504,46 +518,62 @@
int cg_migrate_recursive_fallback(
const char *cfrom,
const char *pfrom,
const char *cto,
const char *pto,
CGroupFlags flags) {
int r;
assert(cfrom);
assert(pfrom);
assert(cto);
assert(pto);
r = cg_migrate_recursive(cfrom, pfrom, cto, pto, flags);
if (r < 0) {
char prefix[strlen(pto) + 1];
/* This didn't work? Then let's try all prefixes of the destination */
PATH_FOREACH_PREFIX(prefix, pto) {
int q;
+ /*
+ * PSz 23 Jul 2017
+ * Skip an empty ("") prefix path: surely wrong,
+ * do not annoy cgroups that are not ours.
+ * Other comments:
+ * - Why this "did not work so try something else"?
+ * - Maybe should have used PATH_FOREACH_PREFIX_MORE
+ * for cleaner, more compact code.
+ * - Should check cg_attach_fallback() also, and maybe
+ * review all other uses of PATH_FOREACH_PREFIX.
+ */
+ if (!strlen(prefix)) {
+ /* log_warning("PSz debug: cg_migrate_recursive_fallback skip from (%s)%s to (%s) (empty prefix of %s)", cfrom, pfrom, cto, pto); */
+ continue;
+ }
+
q = cg_migrate_recursive(cfrom, pfrom, cto, prefix, flags);
if (q >= 0)
return q;
}
}
return r;
}
static const char *controller_to_dirname(const char *controller) {
const char *e;
assert(controller);
/* Converts a controller name to the directory name below
* /sys/fs/cgroup/ we want to mount it to. Effectively, this
* just cuts off the name= prefixed used for named
* hierarchies, if it is specified. */
e = startswith(controller, "name=");
if (e)
return e;
_______________________________________________
Pkg-systemd-maintainers mailing list
[email protected]
http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/pkg-systemd-maintainers
