Chen Ridong f371ad6471 Revert "cgroup_freezer: cgroup_freezing: Check if not frozen" ... [ Upstream commit 14a67b42cb ] This reverts commit cff5f49d43. Commit cff5f49d43 ("cgroup_freezer: cgroup_freezing: Check if not frozen") modified the cgroup_freezing() logic to verify that the FROZEN flag is not set, affecting the return value of the freezing() function, in order to address a warning in __thaw_task. A race condition exists that may allow tasks to escape being frozen. The following scenario demonstrates this issue: CPU 0 (get_signal path) CPU 1 (freezer.state reader) try_to_freeze read freezer.state __refrigerator freezer_read update_if_frozen WRITE_ONCE(current->__state, TASK_FROZEN); ... /* Task is now marked frozen */ /* frozen(task) == true */ /* Assuming other tasks are frozen */ freezer->state |= CGROUP_FROZEN; /* freezing(current) returns false */ /* because cgroup is frozen (not freezing) */ break out __set_current_state(TASK_RUNNING); /* Bug: Task resumes running when it should remain frozen */ The existing !frozen(p) check in __thaw_task makes the WARN_ON_ONCE(freezing(p)) warning redundant. Removing this warning enables reverting the commit cff5f49d43 ("cgroup_freezer: cgroup_freezing: Check if not frozen") to resolve the issue. The warning has been removed in the previous patch. This patch revert the commit cff5f49d43 ("cgroup_freezer: cgroup_freezing: Check if not frozen") to complete the fix. Fixes: cff5f49d43 ("cgroup_freezer: cgroup_freezing: Check if not frozen") Reported-by: Zhong Jiawei<zhongjiawei1@huawei.com> Signed-off-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2025-07-24 08:53:20 +02:00
..
cgroup-internal.h	cgroup: Make operations on the cgroup root_list RCU safe	2024-08-19 06:04:25 +02:00
cgroup-v1.c	kernfs: Convert kernfs_path_from_node_locked() from strlcpy() to strscpy()	2024-08-03 08:53:21 +02:00
cgroup.c	cgroup: Fix compilation issue due to cgroup_mutex not being exported	2025-06-04 14:41:53 +02:00
cpuset.c	cgroup/cpuset: Extend kthread_is_per_cpu() check to all PF_NO_SETAFFINITY tasks	2025-05-22 14:12:12 +02:00
debug.c
freezer.c
legacy_freezer.c	Revert "cgroup_freezer: cgroup_freezing: Check if not frozen"	2025-07-24 08:53:20 +02:00
Makefile
misc.c
namespace.c
pids.c
rdma.c
rstat.c	cgroup: Remove steal time from usage_usec	2025-02-21 13:57:08 +01:00