Commit 8b5a5a9dbca914d1f7d70276024d1525a3c94081
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dd775ae254
Exists in
smarc-l5.0.0_1.0.0-ga
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cgroup: deprecate remount option changes
This patch marks the following features for deprecation.
* Rebinding subsys by remount: Never reached useful state - only works
on empty hierarchies.
* release_agent update by remount: release_agent itself will be
replaced with conventional fsnotify notification.
v2: Lennart pointed out that "name=" is necessary for mounts w/o any
controller attached. Drop "name=" deprecation.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Lennart Poettering <mzxreary@0pointer.de>
Showing 2 changed files with 14 additions and 0 deletions Side-by-side Diff
Documentation/feature-removal-schedule.txt
| ... | ... | @@ -539,4 +539,13 @@ |
| 539 | 539 | of ASLR. It was only ever intended for debugging, so it should be |
| 540 | 540 | removed. |
| 541 | 541 | Who: Kees Cook <keescook@chromium.org> |
| 542 | + | |
| 543 | +---------------------------- | |
| 544 | + | |
| 545 | +What: cgroup option updates via remount | |
| 546 | +When: March 2013 | |
| 547 | +Why: Remount currently allows changing bound subsystems and | |
| 548 | + release_agent. Rebinding is hardly useful as it only works | |
| 549 | + when the hierarchy is empty and release_agent itself should be | |
| 550 | + replaced with conventional fsnotify. |
kernel/cgroup.c
| ... | ... | @@ -1294,6 +1294,11 @@ |
| 1294 | 1294 | if (ret) |
| 1295 | 1295 | goto out_unlock; |
| 1296 | 1296 | |
| 1297 | + /* See feature-removal-schedule.txt */ | |
| 1298 | + if (opts.subsys_bits != root->actual_subsys_bits || opts.release_agent) | |
| 1299 | + pr_warning("cgroup: option changes via remount are deprecated (pid=%d comm=%s)\n", | |
| 1300 | + task_tgid_nr(current), current->comm); | |
| 1301 | + | |
| 1297 | 1302 | /* Don't allow flags or name to change at remount */ |
| 1298 | 1303 | if (opts.flags != root->flags || |
| 1299 | 1304 | (opts.name && strcmp(opts.name, root->name))) { |