From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sat, 16 Dec 2000 22:21:28 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sat, 16 Dec 2000 22:21:19 -0500 Received: from p050.as-l001.contactel.cz ([212.65.194.50]:2564 "EHLO ppc.vc.cvut.cz") by vger.kernel.org with ESMTP id ; Sat, 16 Dec 2000 22:21:15 -0500 Date: Sun, 17 Dec 2000 03:49:28 +0100 From: Petr Vandrovec To: linux-kernel@vger.kernel.org Cc: torvalds@transmeta.com Subject: 2.4.0-test13-pre1 lockup: run_task_queue or tty_io are wrong Message-ID: <20001217034928.A410@ppc.vc.cvut.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, my 2.4.0-test13-pre1 just stopped answering to my keystrokes. I've found that it is looping in tqueue_bh and flush_to_ldisc still again and again. To my surprise I found that flush_to_ldisc() does if (test_bit(TTY_DONT_FLIP, &tty_flags)) { queue_task(&tty->filp.tqueue, &tq_timer); return; } Looks ok. But only until you'll look at run_task_queue(). It now contains while (!list_empty(list)) { ... } So postponing event to next timer tick does not work anymore. It will stop cycling in run_task_queue and machine is dead (unless you have some spare CPU). Is current run_task_queue() behavior intentional, or is it only bug introduced by changing task queue to list based implementation? Thanks, Petr Vandrovec vandrove@vc.cvut.cz P.S.: Yes, I know that I should bought faster computer so that ldisc buffer does not overflow, but... - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/