From b3f68f16dbcde6fcdf0fd27695391ff7e9d41233 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Sun, 26 Aug 2012 21:12:14 +0200 Subject: task_work: Revert "hold task_lock around checks in keyctl" This reverts commit d35abdb28824cf74f0a106a0f9c6f3ff700a35bf. task_lock() was added to ensure exit_mm() and thus exit_task_work() is not possible before task_work_add(). This is wrong, task_lock() must not be nested with write_lock(tasklist). And this is no longer needed, task_work_add() now fails if it is called after exit_task_work(). Reported-by: Dave Jones Signed-off-by: Oleg Nesterov Signed-off-by: Peter Zijlstra Cc: Al Viro Cc: Linus Torvalds Cc: Andrew Morton Link: http://lkml.kernel.org/r/20120826191214.GA4231@redhat.com Signed-off-by: Ingo Molnar --- security/keys/keyctl.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c index 3364fbf..6cfc647 100644 --- a/security/keys/keyctl.c +++ b/security/keys/keyctl.c @@ -1486,7 +1486,6 @@ long keyctl_session_to_parent(void) oldwork = NULL; parent = me->real_parent; - task_lock(parent); /* the parent mustn't be init and mustn't be a kernel thread */ if (parent->pid <= 1 || !parent->mm) goto unlock; @@ -1530,7 +1529,6 @@ long keyctl_session_to_parent(void) if (!ret) newwork = NULL; unlock: - task_unlock(parent); write_unlock_irq(&tasklist_lock); rcu_read_unlock(); if (oldwork) -- cgit v1.1