summaryrefslogtreecommitdiff
path: root/kernel/cpuset.c
diff options
context:
space:
mode:
authorTejun Heo <tj@kernel.org>2015-09-19 00:54:23 +0300
committerTejun Heo <tj@kernel.org>2015-09-19 00:54:23 +0300
commit7dbdb199d3bf88f043ea17e97113eb28d5b100bc (patch)
tree648451cd5f719dafe1c01a18cf2a7903d6166f93 /kernel/cpuset.c
parent4a07c222d3afb00e1113834fee38d23a8e5d71dc (diff)
downloadlinux-7dbdb199d3bf88f043ea17e97113eb28d5b100bc.tar.xz
cgroup: replace cftype->mode with CFTYPE_WORLD_WRITABLE
cftype->mode allows controllers to give arbitrary permissions to interface knobs. Except for "cgroup.event_control", the existing uses are spurious. * Some explicitly specify S_IRUGO | S_IWUSR even though that's the default. * "cpuset.memory_pressure" specifies S_IRUGO while also setting a write callback which returns -EACCES. All it needs to do is simply not setting a write callback. "cgroup.event_control" uses cftype->mode to make the file world-writable. It's a misdesigned interface and we don't want controllers to be tweaking interface file permissions in general. This patch removes cftype->mode and all its spurious uses and implements CFTYPE_WORLD_WRITABLE for "cgroup.event_control" which is marked as compatibility-only. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Li Zefan <lizefan@huawei.com> Cc: Johannes Weiner <hannes@cmpxchg.org>
Diffstat (limited to 'kernel/cpuset.c')
-rw-r--r--kernel/cpuset.c6
1 files changed, 0 insertions, 6 deletions
diff --git a/kernel/cpuset.c b/kernel/cpuset.c
index 20eedd8098c0..312961ef3ccc 100644
--- a/kernel/cpuset.c
+++ b/kernel/cpuset.c
@@ -1597,9 +1597,6 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft,
case FILE_MEMORY_PRESSURE_ENABLED:
cpuset_memory_pressure_enabled = !!val;
break;
- case FILE_MEMORY_PRESSURE:
- retval = -EACCES;
- break;
case FILE_SPREAD_PAGE:
retval = update_flag(CS_SPREAD_PAGE, cs, val);
break;
@@ -1866,9 +1863,6 @@ static struct cftype files[] = {
{
.name = "memory_pressure",
.read_u64 = cpuset_read_u64,
- .write_u64 = cpuset_write_u64,
- .private = FILE_MEMORY_PRESSURE,
- .mode = S_IRUGO,
},
{