diff --git a/libcontainer/cgroups/utils.go b/libcontainer/cgroups/utils.go index c26be8cd2c6..8824fc22d29 100644 --- a/libcontainer/cgroups/utils.go +++ b/libcontainer/cgroups/utils.go @@ -16,6 +16,7 @@ import ( "time" "github.com/opencontainers/runc/libcontainer/cgroups/fscommon" + "github.com/opencontainers/runc/libcontainer/system" "github.com/sirupsen/logrus" "golang.org/x/sys/unix" ) @@ -34,8 +35,15 @@ var ( func IsCgroup2UnifiedMode() bool { isUnifiedOnce.Do(func() { var st unix.Statfs_t - if err := unix.Statfs(unifiedMountpoint, &st); err != nil { - panic("cannot statfs cgroup root") + err := unix.Statfs(unifiedMountpoint, &st) + if err != nil { + if os.IsNotExist(err) && system.RunningInUserNS() { + // ignore the "not found" error if running in userns + logrus.WithError(err).Debugf("%s missing, assuming cgroup v1", unifiedMountpoint) + isUnified = false + return + } + panic(fmt.Sprintf("cannot statfs cgroup root: %s", err)) } isUnified = st.Type == unix.CGROUP2_SUPER_MAGIC })