)]}'
{
  "commit": "14a67b42cb6f3ab66f41603c062c5056d32ea7dd",
  "tree": "9406b196c4c091054022e1e15d4cf5e019a3c7c1",
  "parents": [
    "9beb8c5e77dc10e3889ff5f967eeffba78617a88"
  ],
  "author": {
    "name": "Chen Ridong",
    "email": "chenridong@huawei.com",
    "time": "Thu Jul 17 08:55:50 2025 +0000"
  },
  "committer": {
    "name": "Tejun Heo",
    "email": "tj@kernel.org",
    "time": "Thu Jul 17 07:57:02 2025 -1000"
  },
  "message": "Revert \"cgroup_freezer: cgroup_freezing: Check if not frozen\"\n\nThis reverts commit cff5f49d433fcd0063c8be7dd08fa5bf190c6c37.\n\nCommit cff5f49d433f (\"cgroup_freezer: cgroup_freezing: Check if not\nfrozen\") modified the cgroup_freezing() logic to verify that the FROZEN\nflag is not set, affecting the return value of the freezing() function,\nin order to address a warning in __thaw_task.\n\nA race condition exists that may allow tasks to escape being frozen. The\nfollowing scenario demonstrates this issue:\n\nCPU 0 (get_signal path)\t\tCPU 1 (freezer.state reader)\ntry_to_freeze\t\t\tread freezer.state\n__refrigerator\t\t\tfreezer_read\n\t\t\t\tupdate_if_frozen\nWRITE_ONCE(current-\u003e__state, TASK_FROZEN);\n\t\t\t\t...\n\t\t\t\t/* Task is now marked frozen */\n\t\t\t\t/* frozen(task) \u003d\u003d true */\n\t\t\t\t/* Assuming other tasks are frozen */\n\t\t\t\tfreezer-\u003estate |\u003d CGROUP_FROZEN;\n/* freezing(current) returns false */\n/* because cgroup is frozen (not freezing) */\nbreak out\n__set_current_state(TASK_RUNNING);\n/* Bug: Task resumes running when it should remain frozen */\n\nThe existing !frozen(p) check in __thaw_task makes the\nWARN_ON_ONCE(freezing(p)) warning redundant. Removing this warning enables\nreverting the commit cff5f49d433f (\"cgroup_freezer: cgroup_freezing: Check\nif not frozen\") to resolve the issue.\n\nThe warning has been removed in the previous patch. This patch revert the\ncommit cff5f49d433f (\"cgroup_freezer: cgroup_freezing: Check if not\nfrozen\") to complete the fix.\n\nFixes: cff5f49d433f (\"cgroup_freezer: cgroup_freezing: Check if not frozen\")\nReported-by: Zhong Jiawei\u003czhongjiawei1@huawei.com\u003e\nSigned-off-by: Chen Ridong \u003cchenridong@huawei.com\u003e\nSigned-off-by: Tejun Heo \u003ctj@kernel.org\u003e\n",
  "tree_diff": [
    {
      "type": "modify",
      "old_id": "507b8f19a262e06460707ef0e543a7ab94cb39d9",
      "old_mode": 33188,
      "old_path": "kernel/cgroup/legacy_freezer.c",
      "new_id": "dd9417425d9292cf5f6801b16ed7ade2427b040d",
      "new_mode": 33188,
      "new_path": "kernel/cgroup/legacy_freezer.c"
    }
  ]
}