Hello Roman, Roman Gushchin <guro@xxxxxx> writes: > Hi Richard! > >> SLAB objects which outlive their memcg are moved to their parent >> memcg where they may be uncharged. However if they are moved to the >> root memcg, uncharging will result in negative page counter values as >> root has no page counters. >> >> To prevent this, we check whether we are about to uncharge the root >> memcg and skip it if we are. Possibly instead; the obj_cgroups should >> be removed from their slabs and any per cpu stocks instead of >> reparenting them to root? > > It would be really complex. I think your fix is totally fine. > We have similar checks in cancel_charge(), uncharge_batch(), > mem_cgroup_swapout(), mem_cgroup_uncharge_swap() etc. > > > Acked-by: Roman Gushchin <guro@xxxxxx> > > Thanks! Great I will respin. -- Thank you, Richard.
