From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with SMTP id 09F046B01EB for ; Wed, 24 Mar 2010 12:25:17 -0400 (EDT) Received: by ewy5 with SMTP id 5so1504823ewy.10 for ; Wed, 24 Mar 2010 09:25:15 -0700 (PDT) From: Anfei Zhou Subject: [PATCH] oom killer: break from infinite loop Date: Thu, 25 Mar 2010 00:25:05 +0800 Message-Id: <1269447905-5939-1-git-send-email-anfei.zhou@gmail.com> Sender: owner-linux-mm@kvack.org To: akpm@linux-foundation.org, rientjes@google.com, kosaki.motohiro@jp.fujitsu.com, nishimura@mxp.nes.nec.co.jp, kamezawa.hiroyu@jp.fujitsu.com Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: In multi-threading environment, if the current task(A) have got the mm->mmap_sem semaphore, and the thread(B) in the same process is selected to be oom killed, because they shares the same semaphore, thread B can not really be killed. So __alloc_pages_slowpath turns to be a infinite loop. Here set all the threads in the group to TIF_MEMDIE, it gets a chance to break and exit. Signed-off-by: Anfei Zhou --- mm/oom_kill.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) diff --git a/mm/oom_kill.c b/mm/oom_kill.c index 9b223af..aab9892 100644 --- a/mm/oom_kill.c +++ b/mm/oom_kill.c @@ -381,6 +381,8 @@ static void dump_header(struct task_struct *p, gfp_t gfp_mask, int order, */ static void __oom_kill_task(struct task_struct *p, int verbose) { + struct task_struct *t; + if (is_global_init(p)) { WARN_ON(1); printk(KERN_WARNING "tried to kill init!\n"); @@ -412,6 +414,8 @@ static void __oom_kill_task(struct task_struct *p, int verbose) */ p->rt.time_slice = HZ; set_tsk_thread_flag(p, TIF_MEMDIE); + for (t = next_thread(p); t != p; t = next_thread(t)) + set_tsk_thread_flag(t, TIF_MEMDIE); force_sig(SIGKILL, p); } -- 1.6.4.rc1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org