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-rw-r--r--sched-Remove-lockdep-check-in-sched_move_task.patch49
1 files changed, 0 insertions, 49 deletions
diff --git a/sched-Remove-lockdep-check-in-sched_move_task.patch b/sched-Remove-lockdep-check-in-sched_move_task.patch
deleted file mode 100644
index b740be10d..000000000
--- a/sched-Remove-lockdep-check-in-sched_move_task.patch
+++ /dev/null
@@ -1,49 +0,0 @@
-From: Kirill Tkhai <ktkhai@parallels.com>
-Date: Tue, 28 Oct 2014 08:24:34 +0300
-Subject: [PATCH] sched: Remove lockdep check in sched_move_task()
-
-sched_move_task() is the only interface to change sched_task_group:
-cpu_cgrp_subsys methods and autogroup_move_group() use it.
-
-Everything is synchronized by task_rq_lock(), so cpu_cgroup_attach()
-is ordered with other users of sched_move_task(). This means we do no
-need RCU here: if we've dereferenced a tg here, the .attach method
-hasn't been called for it yet.
-
-Thus, we should pass "true" to task_css_check() to silence lockdep
-warnings.
-
-Fixes: eeb61e53ea19 ("sched: Fix race between task_group and sched_task_group")
-Reported-by: Oleg Nesterov <oleg@redhat.com>
-Reported-by: Fengguang Wu <fengguang.wu@intel.com>
-Signed-off-by: Kirill Tkhai <ktkhai@parallels.com>
-Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
-Cc: Linus Torvalds <torvalds@linux-foundation.org>
-Link: http://lkml.kernel.org/r/1414473874.8574.2.camel@tkhai
-Signed-off-by: Ingo Molnar <mingo@kernel.org>
----
- kernel/sched/core.c | 8 ++++++--
- 1 file changed, 6 insertions(+), 2 deletions(-)
-
-diff --git a/kernel/sched/core.c b/kernel/sched/core.c
-index 240157c13ddc..6841fb46eb07 100644
---- a/kernel/sched/core.c
-+++ b/kernel/sched/core.c
-@@ -7444,8 +7444,12 @@ void sched_move_task(struct task_struct *tsk)
- if (unlikely(running))
- put_prev_task(rq, tsk);
-
-- tg = container_of(task_css_check(tsk, cpu_cgrp_id,
-- lockdep_is_held(&tsk->sighand->siglock)),
-+ /*
-+ * All callers are synchronized by task_rq_lock(); we do not use RCU
-+ * which is pointless here. Thus, we pass "true" to task_css_check()
-+ * to prevent lockdep warnings.
-+ */
-+ tg = container_of(task_css_check(tsk, cpu_cgrp_id, true),
- struct task_group, css);
- tg = autogroup_task_group(tsk, tg);
- tsk->sched_task_group = tg;
---
-1.9.3
-