Merge tag 'cgroup-for-6.16-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

torvalds · torvalds · commit 74b4cc9b8780 · 2025-06-18T14:25:50.000-07:00
Pull cgroup fix from Tejun Heo:

 - In cgroup1 freezer, a task migrating into a frozen cgroup might not
   get frozen immediately due to the wrong operation order. Fix it.

* tag 'cgroup-for-6.16-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup,freezer: fix incomplete freezing when attaching tasks
diff --git a/kernel/cgroup/legacy_freezer.c b/kernel/cgroup/legacy_freezer.c
@@ -188,13 +188,12 @@ static void freezer_attach(struct cgroup_taskset *tset)
 		if (!(freezer->state & CGROUP_FREEZING)) {
 			__thaw_task(task);
 		} else {
-			freeze_task(task);
-
 			/* clear FROZEN and propagate upwards */
 			while (freezer && (freezer->state & CGROUP_FROZEN)) {
 				freezer->state &= ~CGROUP_FROZEN;
 				freezer = parent_freezer(freezer);
 			}
+			freeze_task(task);
 		}
 	}
 

Original file line number	Diff line number	Diff line change
`@@ -188,13 +188,12 @@ static void freezer_attach(struct cgroup_taskset *tset)`
`188`	`188`	`if (!(freezer->state & CGROUP_FREEZING)) {`
`189`	`189`	`__thaw_task(task);`
`190`	`190`	`} else {`
`191`		`- freeze_task(task);`
`192`		`-`
`193`	`191`	`/* clear FROZEN and propagate upwards */`
`194`	`192`	`while (freezer && (freezer->state & CGROUP_FROZEN)) {`
`195`	`193`	`freezer->state &= ~CGROUP_FROZEN;`
`196`	`194`	`freezer = parent_freezer(freezer);`
`197`	`195`	`}`
	`196`	`+ freeze_task(task);`
`198`	`197`	`}`
`199`	`198`	`}`
`200`	`199`