diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-03-08 11:57:38 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-03-08 11:57:38 -0800 |
commit | ca62eec4e524591b82d9edf7a18e3ae6b691517d (patch) | |
tree | 38dee50b3e587e237103a5b07ff1b8062b13244d | |
parent | 15b04859a21358f8aec1c06b4604877d604b05ee (diff) | |
parent | 99afb0fd5f05aac467ffa85c36778fec4396209b (diff) | |
download | linux-stable-ca62eec4e524591b82d9edf7a18e3ae6b691517d.tar.gz linux-stable-ca62eec4e524591b82d9edf7a18e3ae6b691517d.tar.bz2 linux-stable-ca62eec4e524591b82d9edf7a18e3ae6b691517d.zip |
Merge branch 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
Pull cgroup fixes from Tejun Heo:
"Two cpuset locking fixes from Li. Both tagged for -stable"
* 'for-3.14-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: fix a race condition in __cpuset_node_allowed_softwall()
cpuset: fix a locking issue in cpuset_migrate_mm()
-rw-r--r-- | kernel/cpuset.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c index 4410ac6a55f1..e6b1b66afe52 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -974,12 +974,6 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, * Temporarilly set tasks mems_allowed to target nodes of migration, * so that the migration code can allocate pages on these nodes. * - * Call holding cpuset_mutex, so current's cpuset won't change - * during this call, as manage_mutex holds off any cpuset_attach() - * calls. Therefore we don't need to take task_lock around the - * call to guarantee_online_mems(), as we know no one is changing - * our task's cpuset. - * * While the mm_struct we are migrating is typically from some * other task, the task_struct mems_allowed that we are hacking * is for our current task, which must allocate new pages for that @@ -996,8 +990,10 @@ static void cpuset_migrate_mm(struct mm_struct *mm, const nodemask_t *from, do_migrate_pages(mm, from, to, MPOL_MF_MOVE_ALL); + rcu_read_lock(); mems_cs = effective_nodemask_cpuset(task_cs(tsk)); guarantee_online_mems(mems_cs, &tsk->mems_allowed); + rcu_read_unlock(); } /* @@ -2486,9 +2482,9 @@ int __cpuset_node_allowed_softwall(int node, gfp_t gfp_mask) task_lock(current); cs = nearest_hardwall_ancestor(task_cs(current)); + allowed = node_isset(node, cs->mems_allowed); task_unlock(current); - allowed = node_isset(node, cs->mems_allowed); mutex_unlock(&callback_mutex); return allowed; } |