Found on focal v5.11 kernels (but not v5.8): 5.11.0-1009-aws (AWS c4.8xlarge) and 5.11.0-22-generic (Azure Standard_F32s_v2). It seems it fails only on bigger instances (32 CPUs or more).
On Focal v5.11 it might be slightly different issue:
#####
memcg_use_hierarchy_test 1 TINFO: set /dev/memcg/memory.use_hierarchy to 0 failed
memcg_use_hierarchy_test 1 TINFO: test if one of the ancestors goes over its limit, the proces will be killed
mkdir: cannot create directory ‘subgroup’: Cannot allocate memory
/home/ubuntu/ltp-install/testcases/bin/memcg_use_hierarchy_test.sh: 22: cd: can't cd to subgroup
memcg_use_hierarchy_test 1 TINFO: Running memcg_process --mmap-lock1 -s 8192
memcg_use_hierarchy_test 1 TFAIL: process is not killed
rmdir: failed to remove 'subgroup': No such file or directory
#####
Found on focal v5.11 kernels (but not v5.8): 5.11.0-1009-aws (AWS c4.8xlarge) and 5.11.0-22-generic (Azure Standard_F32s_v2). It seems it fails only on bigger instances (32 CPUs or more).
On Focal v5.11 it might be slightly different issue: hierarchy_ test 1 TINFO: set /dev/memcg/ memory. use_hierarchy to 0 failed hierarchy_ test 1 TINFO: test if one of the ancestors goes over its limit, the proces will be killed ltp-install/ testcases/ bin/memcg_ use_hierarchy_ test.sh: 22: cd: can't cd to subgroup hierarchy_ test 1 TINFO: Running memcg_process --mmap-lock1 -s 8192 hierarchy_ test 1 TFAIL: process is not killed
#####
memcg_use_
memcg_use_
mkdir: cannot create directory ‘subgroup’: Cannot allocate memory
/home/ubuntu/
memcg_use_
memcg_use_
rmdir: failed to remove 'subgroup': No such file or directory
#####