Gitweb: http://git.kernel.org/git/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=5fcc57f2d5d558056668159f9153bf21d2c53d16 Commit: 5fcc57f2d5d558056668159f9153bf21d2c53d16 Parent: a076e4bca2fdabb9e45d86722cc72c0944da5f94 Author: Gautham R Shenoy <[EMAIL PROTECTED]> AuthorDate: Wed May 23 13:57:28 2007 -0700 Committer: Linus Torvalds <[EMAIL PROTECTED]> CommitDate: Wed May 23 20:14:11 2007 -0700
freezer: fix PF_NOFREEZE vs freezeable race This patch fixes the race pointed out by Oleg Nesterov. * Freezer marks a thread as freezeable. * The thread now marks itself PF_NOFREEZE, but it will be frozen on on calling try_to_freeze(). Thus the task is frozen, even though it doesn't want to. * Subsequent thaw_processes() will also fail to thaw the task since it is marked PF_NOFREEZE. Avoid this problem by checking the task's PF_NOFREEZE status in frozen_processes() before marking the task as frozen. Signed-off-by: Gautham R Shenoy <[EMAIL PROTECTED]> Signed-off-by: Rafael J. Wysocki <[EMAIL PROTECTED]> Cc: Oleg Nesterov <[EMAIL PROTECTED]> Cc: Pavel Machek <[EMAIL PROTECTED]> Cc: "Eric W. Biederman" <[EMAIL PROTECTED]> Signed-off-by: Andrew Morton <[EMAIL PROTECTED]> Signed-off-by: Linus Torvalds <[EMAIL PROTECTED]> --- include/linux/freezer.h | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/include/linux/freezer.h b/include/linux/freezer.h index c943525..1045ee9 100644 --- a/include/linux/freezer.h +++ b/include/linux/freezer.h @@ -63,8 +63,10 @@ static inline int thaw_process(struct task_struct *p) */ static inline void frozen_process(struct task_struct *p) { - p->flags |= PF_FROZEN; - wmb(); + if (!unlikely(p->flags & PF_NOFREEZE)) { + p->flags |= PF_FROZEN; + wmb(); + } clear_tsk_thread_flag(p, TIF_FREEZE); } - To unsubscribe from this list: send the line "unsubscribe git-commits-head" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html