[patch 3/3] simplify audit_free() locking

From: Ingo Molnar <mingo(a)elte.hu&gt; Simplify audit_free()'s locking: no need to lock a task that we are tearing down. [the extra locking also caused false positives in the lock validator] Signed-off-by: Ingo Molnar <mingo(a)elte.hu&gt; Cc: David Woodhouse <dwmw2(a)infradead.org&gt; Signed-off-by: Andrew Morton <akpm(a)osdl.org&gt; --- kernel/auditsc.c | 10 +++++++--- 1 files changed, 7 insertions(+), 3 deletions(-) diff -puN kernel/auditsc.c~simplify-audit_free-locking kernel/auditsc.c --- devel/kernel/auditsc.c~simplify-audit_free-locking 2006-02-21 19:11:13.000000000 -0800 +++ devel-akpm/kernel/auditsc.c 2006-02-21 19:11:13.000000000 -0800 @@ -686,10 +686,14 @@ void audit_free(struct task_struct *tsk) { struct audit_context *context; - task_lock(tsk); + /* + * No need to lock the task - when we execute audit_free() + * then the task has no external references anymore, and + * we are tearing it down. (The locking also confuses + * DEBUG_LOCKDEP - this freeing may occur in softirq + * contexts as well, via RCU.) + */ context = audit_get_context(tsk, 0, 0); - task_unlock(tsk); - if (likely(!context)) return; _