The patch titled Subject: mm: memcontrol: add sanity checks for memcg->id.ref on get/put has been removed from the -mm tree. Its filename was mm-memcontrol-add-sanity-checks-for-memcg-idref-on-get-put.patch This patch was dropped because an updated version will be merged ------------------------------------------------------ From: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Subject: mm: memcontrol: add sanity checks for memcg->id.ref on get/put Link: http://lkml.kernel.org/r/ad702144f24374cbfb3a35b71658a0ae24ba7d84.1470057819.git.vdavydov@xxxxxxxxxxxxx Signed-off-by: Vladimir Davydov <vdavydov@xxxxxxxxxxxxx> Cc: Johannes Weiner <hannes@xxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memcontrol.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff -puN mm/memcontrol.c~mm-memcontrol-add-sanity-checks-for-memcg-idref-on-get-put mm/memcontrol.c --- a/mm/memcontrol.c~mm-memcontrol-add-sanity-checks-for-memcg-idref-on-get-put +++ a/mm/memcontrol.c @@ -4079,18 +4079,22 @@ static DEFINE_IDR(mem_cgroup_idr); static void mem_cgroup_id_get_many(struct mem_cgroup *memcg, unsigned int n) { + VM_BUG_ON(atomic_read(&memcg->id.ref) <= 0); atomic_add(n, &memcg->id.ref); } static struct mem_cgroup *mem_cgroup_id_get_active(struct mem_cgroup *memcg) { - while (!atomic_inc_not_zero(&memcg->id.ref)) + while (!atomic_inc_not_zero(&memcg->id.ref)) { + VM_BUG_ON(mem_cgroup_is_root(memcg)); memcg = parent_mem_cgroup(memcg); + } return memcg; } static void mem_cgroup_id_put_many(struct mem_cgroup *memcg, unsigned int n) { + VM_BUG_ON(atomic_read(&memcg->id.ref) < n); if (atomic_sub_and_test(n, &memcg->id.ref)) { idr_remove(&mem_cgroup_idr, memcg->id.id); memcg->id.id = 0; @@ -4211,6 +4215,7 @@ static struct mem_cgroup *mem_cgroup_all INIT_LIST_HEAD(&memcg->cgwb_list); #endif idr_replace(&mem_cgroup_idr, memcg, memcg->id.id); + atomic_set(&memcg->id.ref, 1); return memcg; fail: if (memcg->id.id > 0) @@ -4280,7 +4285,6 @@ fail: static int mem_cgroup_css_online(struct cgroup_subsys_state *css) { /* Online state pins memcg ID, memcg ID pins CSS */ - mem_cgroup_id_get(mem_cgroup_from_css(css)); css_get(css); return 0; } _ Patches currently in -mm which might be from vdavydov@xxxxxxxxxxxxx are mm-oom-deduplicate-victim-selection-code-for-memcg-and-global-oom.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html