From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: Re: [RFC][PATCH -mm 4/6] Freezer: Prevent new tasks from inheriting TIF_FREEZE set Date: Tue, 10 Jul 2007 01:21:13 +0200 Message-ID: <20070709232113.GG1967@elf.ucw.cz> References: <200707092229.08898.rjw@sisk.pl> <200707092234.55437.rjw@sisk.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <200707092234.55437.rjw@sisk.pl> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: "Rafael J. Wysocki" Cc: Matthew Garrett , Miklos Szeredi , pm list , Oleg Nesterov List-Id: linux-pm@vger.kernel.org Hi! > From: Rafael J. Wysocki > > Tasks should go to the refrigerator only if explicitly requested to do that by > the freezer and not as a result of inheriting the TIF_FREEZE flag set from the > parent. Make it happen. Umm, what prevents userspace task from escaping freezer this way? Does tasklist_lock prevent new tasks and thus this race? Pavel > --- linux-2.6.22-rc6-mm1.orig/kernel/fork.c > +++ linux-2.6.22-rc6-mm1/kernel/fork.c > @@ -932,6 +932,7 @@ static inline void copy_flags(unsigned l > if (!(clone_flags & CLONE_PTRACE)) > p->ptrace = 0; > p->flags = new_flags; > + clear_freeze_flag(p); > } > > asmlinkage long sys_set_tid_address(int __user *tidptr) -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html