From: Michal Privoznik <mprivozn@redhat.com>
Date: Thu, 23 Apr 2026 10:05:44 +0000 (+0200)
Subject: vircgroupv2: Freezer controller is implicit
X-Git-Tag: v12.4.0-rc1~154
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=fda330bb8a64e7fb89d46f49506a6fbd037a316b;p=thirdparty%2Flibvirt.git

vircgroupv2: Freezer controller is implicit

The freezer controller in CGroupsV2 is always present (under
cgroup.freeze file). Make our vircgroupv2 backend aware of it.

NB, because of the way our backends are ordered (v2 is prefered)
the v1 freezer is never going to be used when CGroupsV2 are
detected. Hence the change to tests.

NB2, this also fixes output of virt-host-validate which complains
that the 'freezer' controller is not present for LXC driver.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Pavel Hrdina <pavel@hrdina.info>
---

diff --git a/src/util/vircgroupv2.c b/src/util/vircgroupv2.c
index eaf5ae98f6..3fbd67fbda 100644
--- a/src/util/vircgroupv2.c
+++ b/src/util/vircgroupv2.c
@@ -319,6 +319,10 @@ virCgroupV2DetectControllers(virCgroup *group,
      * exists with usage stats. */
     group->unified.controllers |= 1 << VIR_CGROUP_CONTROLLER_CPUACCT;
 
+    /* Similarly, the freezer controller is always available via cgroup.freeze
+     * file. */
+    group->unified.controllers |= 1 << VIR_CGROUP_CONTROLLER_FREEZER;
+
     if (virCgroupV2DevicesAvailable(group))
         group->unified.controllers |= 1 << VIR_CGROUP_CONTROLLER_DEVICES;
 
@@ -480,6 +484,7 @@ virCgroupV2MakeGroup(virCgroup *parent,
 
                 /* Controllers that are implicitly enabled if available. */
                 if (i == VIR_CGROUP_CONTROLLER_CPUACCT ||
+                    i == VIR_CGROUP_CONTROLLER_FREEZER ||
                     i == VIR_CGROUP_CONTROLLER_DEVICES) {
                     continue;
                 }
diff --git a/tests/vircgroupdata/hybrid.parsed b/tests/vircgroupdata/hybrid.parsed
index f755eed465..e92abacc7a 100644
--- a/tests/vircgroupdata/hybrid.parsed
+++ b/tests/vircgroupdata/hybrid.parsed
@@ -3,7 +3,7 @@ cpuacct      <null>
 cpuset       /not/really/sys/fs/cgroup/cpuset
 memory       <null>
 devices      <null>
-freezer      /not/really/sys/fs/cgroup/freezer
+freezer      <null>
 blkio        <null>
 net_cls      /not/really/sys/fs/cgroup/net_cls
 perf_event   /not/really/sys/fs/cgroup/perf_event
diff --git a/tests/vircgrouptest.c b/tests/vircgrouptest.c
index 0e7645af7a..eb85b6d012 100644
--- a/tests/vircgrouptest.c
+++ b/tests/vircgrouptest.c
@@ -529,6 +529,7 @@ static int testCgroupNewForSelfUnified(const void *args G_GNUC_UNUSED)
         (1 << VIR_CGROUP_CONTROLLER_CPUACCT) |
         (1 << VIR_CGROUP_CONTROLLER_MEMORY) |
         (1 << VIR_CGROUP_CONTROLLER_DEVICES) |
+        (1 << VIR_CGROUP_CONTROLLER_FREEZER) |
         (1 << VIR_CGROUP_CONTROLLER_BLKIO);
 
     if (virCgroupNewSelf(&cgroup) < 0) {
@@ -547,13 +548,11 @@ static int testCgroupNewForSelfHybrid(const void *args G_GNUC_UNUSED)
     const char *empty[VIR_CGROUP_CONTROLLER_LAST] = { 0 };
     const char *mounts[VIR_CGROUP_CONTROLLER_LAST] = {
         [VIR_CGROUP_CONTROLLER_CPUSET] = "/not/really/sys/fs/cgroup/cpuset",
-        [VIR_CGROUP_CONTROLLER_FREEZER] = "/not/really/sys/fs/cgroup/freezer",
         [VIR_CGROUP_CONTROLLER_NET_CLS] = "/not/really/sys/fs/cgroup/net_cls",
         [VIR_CGROUP_CONTROLLER_PERF_EVENT] = "/not/really/sys/fs/cgroup/perf_event",
     };
     const char *placement[VIR_CGROUP_CONTROLLER_LAST] = {
         [VIR_CGROUP_CONTROLLER_CPUSET] = "/",
-        [VIR_CGROUP_CONTROLLER_FREEZER] = "/",
         [VIR_CGROUP_CONTROLLER_NET_CLS] = "/",
         [VIR_CGROUP_CONTROLLER_PERF_EVENT] = "/",
     };
@@ -562,6 +561,7 @@ static int testCgroupNewForSelfHybrid(const void *args G_GNUC_UNUSED)
         (1 << VIR_CGROUP_CONTROLLER_CPUACCT) |
         (1 << VIR_CGROUP_CONTROLLER_MEMORY) |
         (1 << VIR_CGROUP_CONTROLLER_DEVICES) |
+        (1 << VIR_CGROUP_CONTROLLER_FREEZER) |
         (1 << VIR_CGROUP_CONTROLLER_BLKIO);
 
     if (virCgroupNewSelf(&cgroup) < 0) {
@@ -619,6 +619,7 @@ static int testCgroupNewForSelfSystemdUnified(const void *args G_GNUC_UNUSED)
         (1 << VIR_CGROUP_CONTROLLER_CPUACCT) |
         (1 << VIR_CGROUP_CONTROLLER_MEMORY) |
         (1 << VIR_CGROUP_CONTROLLER_DEVICES) |
+        (1 << VIR_CGROUP_CONTROLLER_FREEZER) |
         (1 << VIR_CGROUP_CONTROLLER_BLKIO);
 
     if (virCgroupNewSelf(&cgroup) < 0) {