Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757288AbZC0ALl (ORCPT ); Thu, 26 Mar 2009 20:11:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756668AbZC0AKn (ORCPT ); Thu, 26 Mar 2009 20:10:43 -0400 Received: from mx2.redhat.com ([66.187.237.31]:44013 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755899AbZC0AKj (ORCPT ); Thu, 26 Mar 2009 20:10:39 -0400 Date: Fri, 27 Mar 2009 01:06:07 +0100 From: Oleg Nesterov To: Ingo Molnar Cc: Peter Lojkin , Peter Zijlstra , Roland McGrath , linux-kernel@vger.kernel.org, stable@kernel.org Subject: [PATCH 1/2] posix-timers: fix RLIMIT_CPU && fork() Message-ID: <20090327000607.GA10104@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1934 Lines: 56 See http://bugzilla.kernel.org/show_bug.cgi?id=12911 copy_signal() copies signal->rlim, but RLIMIT_CPU is "lost". Because posix_cpu_timers_init_group() sets cputime_expires.prof_exp = 0 and thus fastpath_timer_check() returns false unless we have other expired cpu timers. Change copy_signal() to set cputime_expires.prof_exp if we have RLIMIT_CPU. Also, set cputimer.running = 1 in that case. This is not strictly necessary, but imho makes sense. Reported-by: Peter Lojkin Signed-off-by: Oleg Nesterov --- 6.29/kernel/fork.c~1_FORK 2009-03-23 18:14:34.000000000 +0100 +++ 6.29/kernel/fork.c 2009-03-27 00:25:52.000000000 +0100 @@ -808,6 +808,12 @@ static void posix_cpu_timers_init_group( sig->cputime_expires.virt_exp = cputime_zero; sig->cputime_expires.sched_exp = 0; + if (sig->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) { + sig->cputime_expires.prof_exp = + secs_to_cputime(sig->rlim[RLIMIT_CPU].rlim_cur); + sig->cputimer.running = 1; + } + /* The timer lists. */ INIT_LIST_HEAD(&sig->cpu_timers[0]); INIT_LIST_HEAD(&sig->cpu_timers[1]); @@ -823,11 +829,8 @@ static int copy_signal(unsigned long clo atomic_inc(¤t->signal->live); return 0; } - sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL); - - if (sig) - posix_cpu_timers_init_group(sig); + sig = kmem_cache_alloc(signal_cachep, GFP_KERNEL); tsk->signal = sig; if (!sig) return -ENOMEM; @@ -865,6 +868,8 @@ static int copy_signal(unsigned long clo memcpy(sig->rlim, current->signal->rlim, sizeof sig->rlim); task_unlock(current->group_leader); + posix_cpu_timers_init_group(sig); + acct_init_pacct(&sig->pacct); tty_audit_fork(sig); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/